Sunday, October 2, 2016

Elon Musk Reveals His Plans for Mars

Every year,  the International Astronautical Federation (IAF),  the International Academy of Astronautics (IAA),  and the International Institute of Space Law (IISL) hold a meeting somewhere in the world called the International Astronautical Congress (IAC).  The latest one was September 26-30 in Guadalajara,  Mexico.  The next ones are:

·         2019 - Washington DC, USA; 70th IAC
·         2018 – Bremen, Germany; 69th IAC
·         2017 – Adelaide, Australia; 68th IAC (September 25–29, 2017)[1]

Elon Musk of Spacex gave a very astonishing presentation at that recent meeting,  revealing how he plans to enable a settlement on Mars at an affordable price, sooner than anyone ever thought.  I saw the on-line video of his presentation,  and downloaded the slides he used. 

After taking some time to digest both content,  and the comment and criticism this presentation has generated,  here is my best shot at the most-factual summary.  This is not a full-blown colony that Mr. Musk proposes to establish all by himself,  despite what the news story headlines say. 

He is creating the essential practical transportation system that is necessary to enable many entities to participate in establishing a permanent colony.  No one entity can do this.  The timeline for creating such a colony is around a century long.

Some of the comments I have seen claim Musk is living in “fantasyland”,  because his proposals are so vastly different than anything we have ever seen out of NASA.  They look almost like the 1940’s-1950’s dreams of big spaceships that don’t seem limited in their range. 

But I disagree with the critics;  Musk can now take advantage of enabling technologies and materials today,  that were simply unavailable to NASA or anyone else in prior decades.  If he does embark on this plan,  and he can successfully pull off developing these vehicles and flying them,  it will fundamentally and forever change the world of human space travel. 

Can he do this?  His history says that he does what he says he will do,  but just not quite as fast as he wanted to do it,  because space flight is hard,  with many setbacks.  As proof,  I cite the development of Falcon family of launch vehicles that has so very dramatically helped to reduce the cost of expendable launch to Earth orbit.  Musk has already begun to recover those boosters,  and will soon attempt re-flying them (a key feature of the Mars ship he proposes). 

This isn’t something Musk and Spacex can do all alone.  They have to make money by selling rides in this giant vehicle.  This thing offers something like 300 ton capacity to low Earth orbit,  and at a price per delivered ton far below today’s prices.  This completely opens up the field for entrepreneurs wanting to build space stations in Earth orbit for all sorts of purposes. 

Musk’s “big rocket” is really two things,  a giant launch booster based on scaled-up Falcon technology,  and a spacecraft that is also its second stage getting to orbit.  The booster flies back to launch site for reuse,  and the second stage/spaceship is refueled in orbit to enable it to fly to any desired low-gravity destination,  without further staging. 

Musk's 2-Stage Vehicle with 2nd Stage the Interplanetary Spaceship

Data on the Reusable 1st Stage Booster

 Data on the Reusable 2nd Stage Spaceship (there is a tanker version)

Depiction of Booster Fly-Back Similar to Falcon Boosters

There are actually two versions of that second stage/spaceship:  one is the spaceship that must be refueled in orbit to go anywhere else.  The other version is a tanker that does the refueling in orbit,  and then flies home for reuse.  But,  for the spaceship to come home from its trip,  its crew must make more propellant at that destination.

This thing dwarfs the old Saturn 5 moon rocket.  At launch it’s about 400 feet tall,  3.5 times the weight,  and 3.6 times the thrust,  of the Saturn-5.  It also dwarfs NASA’s three-stage Space Launch System (SLS) rocket,  currently in development,  and which is not reusable at all. 

Comparison of Mars Vehicle and Booster with Saturn-5

There are lots of low-gravity places that a vehicle like this can go.  These include Mars,  our moon,  any moon of Jupiter or Saturn,  and the asteroids and comets.  Maybe Mercury.  Maybe the outer planet moons.  But not high-gravity places like Earth without a booster and tankers.  (Venus isn’t a feasible destination for several reasons besides its gravity.) 

Musk’s schedule calls for development and testing of actual hardware beginning 2018,  aimed at a first Mars flight late in 2022.  Personally,  I think it’ll take a little longer than that,  precisely because space travel is hard and there will be setbacks.  There already have been,  with his Falcon rockets.  But I would guess his Mars ship,  tankers,  and giant booster will be flying no later than about 2030,  maybe a little sooner. 

His presentation showed launches out of Cape Canaveral.  But I think he really wants to launch this thing out of his private space launch facility in deep south Texas.

Location of South Texas Private Launch Site

This thing has enough performance to fly a little faster to Mars than an absolute minimum-energy trajectory.  That shortens trip times considerably,  from 8 months to 3-4 months,  one-way. 

Shorter flight times mean we are “OK” with no artificial gravity and no high-efficiency life support systems,  and that the accumulated space radiation dose is much lower.  There’s plenty of room inside the ship for maybe a hundred people to live,  for journeys of that shorter duration.  Only for further destinations would these issues need to be addressed. 

Once at Mars,  the ship makes a direct entry from its interplanetary trajectory and a retropropulsive landing without parachutes.  Direct entry is something NASA has done for decades with its probes.  Doing propulsive landings without parachutes is something NASA has never done,  except on the moon with Apollo,  and never since.  Problem is,  chutes are ineffective on Mars for masses over about a ton.   

This Mars mission architecture depends upon making propellant on Mars,  because the vehicle uses up all its propellants getting there.  In that sense,  Musk is betting the lives of the ship’s occupants that they can make enough propellants on Mars fast enough to refuel it for the journey home.  It needs no booster to do that:  Mars gravity is only 38% that of Earth.  The ship holds over 1900 tons of propellants,  as currently envisioned.  That’s a lot to make in only a few months!

The choice of which propellants to make is crucial for success.  Musk and Spacex have chosen liquid methane and liquid oxygen,  made with the local Martian “air” (which is 98% carbon dioxide),  and local water-as-ice.  There is a chemical process called “Sabatier” that uses carbon dioxide,  water,  and electricity,  to make methane and oxygen.  Then you liquefy them,  which also requires electricity. 

The key to this is finding local sources of ice to melt for the water.  It means the astronauts are going to have to be ice miners when they get to Mars.  The nature of the buried ice deposits will determine the complexity and weight of the tools,  equipment,  and facilities that the vehicle must transport there. 

If there is a massive buried glacier at the landing site,  then one can simply slant-well drill into it,  use hot steam from a steam generator to melt the subsurface ice,  and bring gobs of water right back up the well.  If the ice veins are thin layers,  or separated pockets,  strip mining will instead be required,  with enormous dirt-moving equipment,  and a gigantic facility processing enormous volumes of surface material,  for each precious ton of water. 

Obviously,  selecting the right landing site is critical. 

Musk’s plans begin with what he already has in-hand today.  There is a new version of the Falcon called Falcon-Heavy,  which should start flying in 2017.  This rocket is powerful enough to send a version of his Dragon capsule unmanned to Mars,  for a direct retropropulsive landing,  with 2+ tons of “stuff” on board. 

That version is called “Red Dragon”,  and will carry as-yet unidentified robotic payloads to investigate multiple potential landing sites.  Musk expects to start these flights in 2018.  NASA is finally participating,  hoping to learn about retropropulsive landings on Mars,  but is too late for them to add any payload items to that first flight.

Depiction of Unmanned Red Dragon Landing on Mars

So,  what would constitute the right landing site?

First,  Musk’s Mars ship is 3-4 times as tall as its landing legs are wide.  That makes it very intolerant of rough ground,  or obstructions like boulders and dunes.   The site must be very flat and clean of hazards. 

Second,  there needs to be massive buried ice deposits directly underneath the landing site.   That’s something remote sensing is just not capable of determining.  Ground truth has always been at variance with remote-sensing claims,  often enormously so. 

It will take real drilling to determine this,  just like it does here exploring for water or for oil/gas/coal.  Whatever payloads Red Dragon carries,  a robot drill rig capable of drilling at least a football-field down is required.          

A Canadian outfit called NORCAT built a robot drill rig that it called “CanaDrill” a few years ago.  They offered it to NASA without success,  my sources tell me.  But,  to me,  it looks like some version of this thing is exactly what Musk needs to ride his Red Dragons to Mars,  looking for that “right” landing site. 

So how will this “play out”? 

Falcon-Heavy/Red Dragon shots identify the right landing site between 2018 and the time the big Mars ship is ready to make its first Mars flight. 

The first big Mars ship flight brings mostly cargo and a small crew.  This crew sets up that first “outpost” as a modest habitat in which to live,  and a minimally-adequate propellant-making plant for the return trip.  They do human exploration of Mars while there,  of course.  As the flights continue every two years when the orbits are favorable,  the propellant plant grows in capacity,  and the habitat also starts enlarging to accommodate larger populations later. 

Based on our history attempting such things so far,  I have very serious doubts that a closed-cycle ecology,  a self-sustaining life support and food production scheme,  is going to be successful in the early years of this outpost.  That means it will initially be dependent upon regular resupply,  as part of the cargoes of these big ships. 

Later on,  this issue will get resolved,  and the outpost becomes essentially self-supporting from a life support/food production standpoint.  That’s the point at which it can first evolve into a real “city on Mars”,  with some serious local production of supplies and infrastructure items (yet to be identified).  By that time,  the ships will be bringing more people than equipment and supplies. 

Eventually,  somewhere in this process,  some sort of Martian exports yet-to-be-identified will be making the return voyages to Earth.  Some sort of interplanetary economy will evolve from that.  That is the point at which you can really call this a proper “colony on Mars”.  I think (as does Musk and Spacex) that’s about a century down the road. 

Comparison to NASA/”Big Space” business-as-usual:

Musk wants people on the surface of Mars by about 2025.  RealisticallyI think he will do this closer to 2030.  Compare that to NASA/”Big Space’s” plans to fly around Mars without landing in the late 2030’s,  with the actual first landing sometime in the 2040’s.  Musk beats them by at least a decade

Musk has already begun to develop his fully-reusable spaceships of enormous cargo capacity.  He has already started landing boosters,  he will soon re-fly used boosters,  he already has a good heat shield for entry at Mars or returning to Earth,  he is already starting to test his methane-oxygen rocket engine (see photo),   and he is already constructing his first giant propellant tank test articles needed for the big booster and ship.  Compare that to the cramped capsules and throw-away stages seen proposed by NASA/”Big Space”,  or by any another entity on the planet. 

Raptor Engine Test (Big Methane-Oxygen Engine)

According to Musk’s presentation,  they are projecting around $200 million per launch of their reusable boosters and ships.  They project a price under $200,000 for each ton delivered to Mars,  which is also roughly the same as the ticket price per person.  Compare that to around $1 billion per launch of NASA’s SLS,  and a per-astronaut cost to Mars in the 10’s of billions of dollars. 

What makes this affordable transportation possible at all,  and what makes this plan look like something out of the dreams from the 1940’s and 1950’s,  is this specific list of enabling technologies,  taken right from Musk’s own slides:  
Reusable vehicles (NASA doesn’t do this,  Virgin Galactic,  Blue Origin,  and XCOR Aerospace do)

Refueling in orbit (NASA doesn’t do this;  the Russians do,  but not with cryogenic propellants)

Select the right propellant that can be manufactured at destination (NASA doesn’t do this,  yet)

Manufacture of said propellant at destination (NASA doesn’t do this,  yet)

This is a total “leap-frog jump” into the futurethat leaves everyone else behind.  I think it is really possible to do this,  although I also think it will be harder to accomplish than it looks to Musk and Spacex right now.  Being a life-long fan of human space travel,  I can only wish them success. 

Update 10-8-16:  There should probably be a 5th item in Mr. Musk's list of 4 enabling items just above:  gigantic size.  He and Spacex have thrown the artificial,  self-imposed "minimum thrown weight" constraint right out the window.  This is unlike anything proposed since the giant spaceship concepts of the mid-1950's.

The New World was not settled from Europe with small boats.  They used the full-size ships of that time.  The airline industry in the US was not started successfully with small airplanes that had only a few passenger seats.  It took Ford leaping in with the Tri-Motor,  and Douglas leaping in with the DC-3,  to point the right way: that large aircraft were what really worked.  The same is true here:  one of the cost savers with Musk's giant rocket is simple economy-of-scale.  

Update 10-28-16:  Do not be confused by the talk of 100 people to Mars per ship,  or colonies with a million people.  That's "far future" stuff,  some decades after the initial landings,  if not longer time spans.  Musk is concentrating on the transportation system,  not the actual establishment of a colony.  He cannot do all of this by himself.  He will be very lucky just to get the transportation system done. 

There is a timeline disparity in what he presented at Guadalajara:  first giant ship to Mars late 2022,  versus first men to Mars late 2024.  This is preceded by Falcon-Heavy/Red Dragon "pathfinder" unmanned shots in 2018,  2020,  and presumably into 2022.  

To me,  this sort-of looks like the first large-ship shot or two is unmanned.  Presumably,  that would have something to do with the return propellant processing factory,  and perhaps other infrastructure,  for a putative manned base to start around 2022.  

And,  as always,  calibrate this with the history so far.  Musk typically does what he says he will do;  it just takes him about 50+% longer than he wanted,  to actually get it done.  


If you go to "Mars Mission Outline 2016" on this site,  dated 5-28-2016,  you can see what I had been working on.  Musk and I share the concepts of big ships,  and of re-usability to the maximum extent possible.  Where we differed was (1) I used separate landers rather than a direct landing,  and (2) I did not presume local propellant manufacturing capability from the very first manned landing.

That is why the two transportation systems look so very different.  Assumptions make a gigantic difference.  

Friday, August 12, 2016

Election 2016 As A Turning Point

Update 11-15-16:

Well,  it's over,  and what I had considered the slightly-greater evil won.  Now the GOP has to put up or shut up.  I rather doubt they have any viable replacements yet,  for the things they want to repeal,  they've been barely competent just being obstructive.

You can always tell when a politician of either party is lying to you:  their lips are moving.  They do not work for us,  they work for whoever bought their jobs for them.  And that's the real root of all this evil.  Political agendas are largely irrelevant in the face of that ugly fact.

Meanwhile,  it does finally seem o be dawning on some other folks that I was right about angry folks left behind economically.  My prescription for how to fix that still stands,  no matter who is in the White House or controls the houses of Congress.

It's "find a way to end the giant corporate welfare state" or get voted out next election.  Now get on with it.  --  GW


There are other related articles on this site,  as listed.  In particular,  see the trade study matrix I did on Clinton versus Trump in “Evaluation of Choices for 2016”,  and the descriptions of where the corporate welfare state comes from in “Stuff You Do Not Normally Think About”.   All share the search keyword “idiocy in politics”.  Here’s the list:

8-4-16….Evaluation of Choices for 2016
7-29-16…..Stuff You Normally Do Not Think About
6-5-16…….Trump?  NO!!
4-24-16….Better Choices in November
12-21-15..Facts Must Trump Politics

The Candidates
Donald Trump has proven over and over that he cannot control himself when he talks.  The very serious risk here is that he cannot control himself when he acts,  especially in a pressure situation.  Many who cannot control their speech also cannot control their actions.  We’ve all seen this.

Therefore,  that risk is completely intolerable for a commander-in-chief with his finger on the nuclear trigger.  So,  in my opinion,  no one with two working brain cells to rub together can vote for Trump for president,  regardless of their politics.  The nuclear extinction risk precludes it.  Extremist politics does have a way of killing brain cells,  doesn’t it?

Hillary Clinton may well be an un-indicted felon.  If 30-40 years ago I had done with classified information what she did at the State Department,  I would still be in jail today,  in a windowless cell.  Which also proves that there really is a double standard of justice,  one for the rich and powerful versus another for the rest of us.   Remember that point about two standards of justice,  I’ll get back to it further below.

She is an integral part of the “political establishment” that has left behind us ordinary folks for 6 decades now.  Given a better choice,  I would not vote for her,  either.

But there is not a better choice.  In her favor,  she knows well the job and all the background associated with it.  And she is stable and well-adjusted and (most importantly) self-controlled enough,  not to go off half-cocked on the nuclear trigger.  She is therefore just barely minimally acceptable to vote for,  as the lesser of the two evils.

The Parties

When I was young,  I tended to vote more Republican than Democrat,  although I am actually a fierce independent.  In those days,  both parties were more “mainstream” in their proposals.  I thought that the Democrats gave away too many tax dollars too easily,  and I did not then know that the Republican approach of “trickle-down economics” was a lie (and well-proven to be so,  ever since Reagan’s time). 

Since then,  the Republicans have extremized their economics and their social policies,  driven there by the “right wing” extremists among them,  and the religious extremists with which they allied.  I personally detest extremism,  whether political or religious.  That way lies the path that has led to war and suffering all these centuries. 

“Detest” may be too weak a word:  such deserve death upon detection.

With Trump bringing in the very-numerous blue-collar “left-behinds”,  there has also been a huge recent influx of racism and bigotry within the party,  although this actually started some years earlier.  Most of the email hit-piece forwards I get are sourced from Republican operatives,  not Democrat operatives,  at least since Bill Clinton’s time.  In some of these,  the racism and bigotry are quite overt,  and I find it very disturbing that friends and neighbors forward this crap to me as if it were true. 

The Democrats have drifted toward the center during those same years.  There are very few “flaming liberals” left in that party,  although there are still some notable exceptions,  such as Bernie Sanders.  Their social agenda is generally more to my liking,  except for their gun control ideas (more on that below).

Historically,  Democrats have been viewed as weak in foreign policy,  but I no longer believe that propaganda.  Democrat President Obama has killed more people with drone strikes than his Republican predecessor ever thought about.  That’s not exactly being “weak”.  FDR and Truman were Democrats,  and so was Teddy Roosevelt,  so that record speaks for itself. 

Actually,  when you get right down to it,  what my grandparents used to say about Republicans is still true:  they favor the rich big businesses over the common man.  It’s just worse now than it was then (more about that below).  What my grandparents used to say about Democrats is no longer true:  instead of favoring the common man,  they,  too,  are now also minions of the giant corporations. 

Libertarians?  Nope.  They want to out-Republican the extremist-Republicans economically.  Which means privatizing or destroying things we really need,  like the public schools.  They want to out-Democrat the Democrats socially,  which is no longer hard to do,  since the Democrats have mostly drifted centrist.  As I said,  I detest extremism.  That is not an agenda I can stomach.

Greens?  No way in hell would I vote for a crackpot anti-vacciner.  With a belief like that,  all other initiatives are also equally suspect.  That’s not “green”,  that’s simply insane.

In summary,  there is little today to recommend any of the parties,  including the two big ones.  Although they are still sort-of better than the two little ones.

Bread and Circuses

Back to two standards of justice.  Or two standards of just about anything.  There’s the rich giants,  and then there’s the rest of us.  Didn’t you ever notice that?  Most of us have been left behind,  as the giants prospered.  And you cannot fight them one-on-one:  they can hire lawyers we cannot afford. 

I’m sorry,  but you no longer live free in a representative democracy anymore.  You haven’t in quite a while.  You are living in a giant corporate welfare state,  in which government now does little but pick your pockets to keep the giants rich.  Your politicians do not work for you who elected them,  they work for these giants who bought their jobs for them.  That’s true for a lot of key appointed officials,  too. 

This has been creeping upon us,  step by slow step,  since World War 2.  The takeover became complete only 20 or 30 years ago,  about the time our party politics extremized into the comic-opera buffoonery we have today.  Take a good hard look at the officials you elect:  are they not clownish buffoons,  by and large?  Did you never wonder why?

My friends and neighbors,  these buffoons and idiotic politics are the bread-and-circuses by which those who rule us hope to keep our attentions diverted,  away from what they have actually done to us.  They have no interest in how badly these clowns govern,  they only care about getting lots of tax money fed to them as this-or-that contract,  while not paying any taxes. 

Have you not noticed that the last air force bomber that actually worked right was the B-52,  first flown in 1952,  and whose very last production example rolled off the assembly line in 1961?  That we now build warships without any guns on them?  That none of the high dollar defense programs produces anything that works right anymore?  And hasn’t for some decades now? 

So where did all your federal gasoline tax dollars go?  Certainly not into keeping the highways and bridges up to par!  Somebody’s pockets somewhere,  that’s for sure!  And not any of us common folk. 

It got this way because of an uncorrected mistake made by the writers of our Constitution:  they allowed lobbyists and their money to roam the halls of government,  without making it the crime of bribery that it actually is.  I guess for them our experiment-in-democracy was experimental enough,  without trying to correct that evil,  too.  They didn’t correct slavery either.  Fallible,  like all of us.

Correcting evils is precisely what the amendment process was for.  At least they got that part right. 

You have to take private money out of the campaigns,  too,  or you never will get anyone worth voting “for”,  only “against”.  That’s even true at the primary level.  This will have to be a sweeping change to be effective. 

It’s way past time to fix all this. 

Making Changes

To me,  it appears there are only 3 options:  (1) voting out all the corrupt officeholders,  so that all lobbyist monies actually can be outlawed by new officials,  at all levels and phases of government,  (2) a grassroots Constitutional amendment to outlaw all lobbyist monies anywhere in any governmental process,  or (3) do armed revolution in the streets and just start over. 

Item (1) voting the crooks out doesn’t seem very feasible,  because a majority of the electorate seems to actually believe the idiotic political propaganda.  I guess they’ve heard it too many times,  and so believe it to be true.  Which is exactly how the Nazis and Communists obtained and retained power.  And how the jihadists do it today.  It’s called the “big lie” technique;  somewhere you’ve heard of that!

There’s enough Trump supporters and Bernie Sanders supporters to actually do this,  if they could but get together.  But they will not.  Idiotic politics gets in the way.  They believe the “big lies”.

Item (2) amending the Constitution to make buying politicians and appointed officials a crime would indeed throw the giant corporations out of power.  But getting everyone to actually agree on one (or more)specific amendment(s) will be more difficult than it would seem at first sight.  This is for precisely the very same reason that we can’t just throw the crooked bums out at the ballot box:  people actually believe in the idiocies that are their politics. 

Item (3) armed revolution is the only one the giant corporations actually fear could really happen.  That is why they have made gun control / creeping gun confiscation a part of the Democratic platform agenda.  So they can use the Democrats to disarm us.  Unarmed populations are easy to dominate:  just ask the Germans and the Russians.  Or many of the peoples of the third world. 

Never forget that the purpose of the Second Amendment was to make the threat of armed revolution credible,  so that government would behave itself.  The Founding Fathers did a pretty good job with that one,  because it could still work today,  even with the de facto takeover by the giant corporations already in place! 

The federal government has been quietly equipping all sorts of non-military,  non-police agencies with machine guns,  body armor,  tactical vehicles,  and immense quantities of ammunition.  Agencies like the EPA and IRS.  What do they need such battle equipment for?  Not for their jobs.  Unless,  they are to be employed as adjunct troops to help quell the armed rebellion.  Think about that!

Don’t get me wrong:  I’d much rather do this at the ballot box in one way or another.  There’s a whole lot less mess to clean up afterwards.  But the prudent and patriotic person simply must be prepared to face the possibility that revolution becomes the only option.

Why Do Anything At All?

What if we do nothing?  Well,  the giant corporations’ policies will eventually lead to the destruction of the middle class.  That’s where the bulk of the tax revenues are coming from.  Certainly not the poor,  they pay none,  and could not pay even if levied.  As for the giants,  paying nothing is exactly why they own the politicians and officials.  The smaller corporations and small businesses are less of a revenue source than the middle class. 

Point is,  the money gravy train ends when the middle class dies.

So,  long term,  this system is not sustainable,  and it will fall.  And utter chaos will result.  We may not recover before getting opportunistically invaded by some other country.  Just like Rome.

Why am I certain this will eventually happen if we do not correct it?  Because money is more addictive than heroin.  All addicts become self-destructive.  Even giant corporations. 

It is in your best self-interest to put an end to this giant corporate welfare state,  before its ultimate fall puts an end to you. 

I recommend we try the two ballot box options before resorting to revolution.  But we need to be prepared,  even for revolution.  Keep your guns and ammo hidden.   We who still own guns still outnumber “them”,  and in city-street fighting house-to-house,  that’s all that really matters. 

Thursday, August 4, 2016

Evaluation of Choices for 2016

Update 10-13-16 is the image just above.  It's perfect!!!

I have been voicing opinions for some months now regarding the 2016 election.  There are some related articles elsewhere on this site,  one of which seems to be modestly popular with readers (the 7-29-16 article).  Another one is just a funny (the 4-24-16 article).  All share the search keyword “idiocy in politics”.  Here’s the list:

8-4-16....Evaluation of Choices for 2016  (this one)
7-29-16…..Stuff You Normally Do Not Think About
6-5-16…….Trump?  NO!!
4-24-16….Better Choices in November
12-21-15..Facts Must Trump Politics

Those of you who know me are aware that I have often said this:  I haven’t been voting “for” anybody for president in a great many years,  I have been voting “against” the ones I consider to be greater evils.  And that’s true “in spades” for 2016. 

Trade Study Evaluation

Long ago,  I learned how to use the “trade matrix” as an analysis tool for making hard choices.  I’ve done it again:  evaluating Clinton vs Trump.  This did not extend to the third/fourth party candidates.

The Libertarians have some really odd policy proposals,  to my way of thinking,  claiming to be socially more liberal than the Democrats,  but economically more conservative than the Republicans.  They want to dismantle too many institutions that we actually need.  

The Greens are led by an anti-vacciner,  in spite of all the science discrediting her notions.  That’s entirely too crackpot to believe.  

So,  it’s just the Democrats vs the Republicans. 

What I did was phrase a bunch of items,  all as negative statements.  A ”yes” means the negative applies to the candidate,  color-coded coded red.  Otherwise,  it does not apply,  color-coded blue.  I did not rank how severely a negative applies,  only that it applies at all.  The only thing I did with the data was to re-order the items,  so that the color coding is much clearer.  The rationale for assigning "yes" vs "no" is given further below,  for those who love details.  Here is the trade study matrix data:

Results and Recommendations

Quite frankly,  there are two conclusions to draw from this pattern of data:  (1) both candidates are “evil” (severely flawed) as indicated by majority red,  and (2),  Trump is the greater evil,  having no blue at all.  I will be voting for the lesser evil (Clinton),  and encourage all of you to do the same.  My best estimate is that Trump,  the greater evil,  would cause chaos-at-the-very-minimum,  if elected. 

Estimates of the Political Landscape

My best guess is that we are seeing the destruction of the Republican party as we have known it.  It hasn’t been the “party of Lincoln” since the coalition of religious and political extremists gained control of it back in Reagan’s time.  This got worse a few years ago with the national Tea Party extremists,  who do not govern,  only obstruct.  And now there is Trump,  whose supporters overwhelmed all the rest in the primary just concluded. 

We actually do need a “party of Lincoln”.  I can do without the rest.

All the time this was happening,  the Democrats morphed into a very centrist party,  with few of the “flaming liberals” that they used to have in spades.  Not all these flaming liberals were bad:  I rather thought well of Hubert Humphrey,  for one.  This year,  there is a leftward lurch to some small extent,  brought about by Bernie Sanders and his supporters. Actually,  that’s a good thing,  we do not need two conservative parties.  Sameness begets no new ideas in debate.

If it were not so pathetic,  this next would actually be funny:  the Trump and Sanders supporters are largely working class / middle class folks left behind by both parties for about 60 years now.  They do not share politics,  but they share a common problem with a common solution:  end the giant corporate welfare state that has replaced our republic.  There’s enough of them together to vote in the changes needed,  but they will not get together,  because of the irrelevant party politics.  Sad.

Both parties have favored the rich giants with tax breaks and government contract money,  to the extent that these left-behind folks are worse off now than they have ever been in history.  And it’s getting even worse:  the rest of the middle class is now also facing destruction.  That’ll be the end of our country,  because that’s where most of the tax money comes from. 

The giants know this,  but persist in taking all the loot anyway,  because greed overwhelms all common sense.  And that is why we are headed to hell in a handbasket.  So many agree with me,  but cannot say why,  really. 

But  I just told you exactly why.  

Explanation of Items (the promised details)

Chronic Liar

According to the fact checkers I can find on-line,  at least about 70% of what DJT says at any given time is untrue.  Some claim near 100%.  Around 30% of what HRC says is untrue,  same sources.  My trade study does not rank more vs less lies,  only that there are lies. 

Demonstrated Cheat

The DNC has been found out to have favored Clinton over Sanders.  I infer that HRC knew this was going on,  and said nothing,  which qualifies as cheating.  DJT used bankruptcies 6 times to “take the money and run”,  stiffing his investors,  his vendors,  and his contractors.  While legal,  most Americans would consider that cheating (abuse of the bankruptcy process for personal gain).  Severity and number of incidents do not factor into my trade study,  only that cheating occurred. 

Slow to Recognize Bad Decisions

Clinton:  support for a trumped-up Iraq invasion,  still not recognized as incorrect;  and telling lies / obstructing the investigation about the Benghazi embassy disaster.  Trump:  chronic use of bankruptcy laws to enrich himself not recognized as morally repugnant for an elected officeholder,  chronic lying not recognized as wrong in any venue, mishandled campaign not recognized as a whole series of bad decisions,  which are destroying the Republican party.

Connected to Rich Elites

Clinton:  politically connected closely to the giant corporations as election funding sources,  same ones who have taken over our government;  she is intimately connected to the immensely powerful Clinton Foundation business enterprise.  Trump:  connected to the rich business community by being part of it.  This is a bad thing because those elites have taken over our government.  Being connected implies the status quo (giant corporate welfare state) will be supported. 

Connected to Overseas Rich

Clinton:  Clinton Foundation receives large amounts of money from foreign contributors.  Trump:  has connections to Russian elites who have invested heavily in him,  who are a Russian version of organized crime.  These issues inherently affect foreign policy. 

Hides Information

Clinton:  long history – Whitewater,  Vince Foster,  Benghazi,  and the unsecured classified emails are the most infamous.  Trump:  will not release tax returns like all other politicians (presumably because they would show he pays no taxes,  and also that he is financially connected to the Russians).  These issues inherently affect foreign and domestic policy,  and undermine credibility.  The relative egregiousness did not figure in to the evaluation,  only that any information was improperly hidden at all. 

Hurts Others

Clinton:  Whitewater was a real estate scam that bilked oldsters out of their savings,  Vince Foster died,  inattention to embassy security got 4 killed in Benghazi,  and she voted for the trumped-up Iraq war that got hundreds of thousands killed for no useful purpose.  Trump:  6 documented bankruptcies that enriched him at the expense of his creditors,  completely stiffed many vendors and contractors,  and sold worthless degrees for lots of money via Trump University.  The relative egregiousness did not figure in,  only that other people got hurt at all. 

Supports Bad Policy Ideas

Clinton:  supports unworkable ideas for more gun control at a time when the public needs to be better armed to retake their country from the giant corporations,  free/cheap college ideas not well thought-out and probably have side effects worse than what is to be “fixed”.  Trump (to the extent that he has any policy ideas at all):  completely unworkable ideas for border control (wall to be paid for by Mexico,  when cheap ladders and shovels easily defeat a very expensive wall),  and immigration security (denying all Muslim immigrants entry is both illegal and immoral). 

Purveyor of Division and Hate

Trump says all Hispanic immigrants are rapists and criminals,  says all Muslim immigrants are terrorists.  Has chronically made atrocious and denigrating remarks about political rivals.  Encourages supporters to get violent with opposition at his rallies,  sometimes directly.  Clinton at least talks inclusive.

Unaware of/Disregards Constitution/Law

Trump wants to temporarily (?) ban Muslim and Mexican immigration in violation of the equal protection guarantees of the Constitution.  He wants to do this with or without Congress,  in violation of the separation of powers in the Constitution.  He wants to abrogate the NATO treaty collective protection if the nation involved hasn’t paid enough.  Clinton has said nothing like those things. 

Ignorant of Foreign Affairs

Trump chronically says egregiously incorrect things,  such as:  Russia isn’t in Ukraine,  Crimea wants to be in Russia,  and many more.  Clinton lied by omission,  not about the facts,  with regard to Benghazi. 

Manipulatable:  Cannot Control Self

Trump is a verbal counterpuncher,  and quite evidently cannot not respond.  If Putin crosses him (and he will,  because that’s his nature),  Trump will respond,  and if commander-in-chief,  could order a nuclear attack.  Putin will manipulate him by this mechanism to bog us down in more foreign wars that we don’t need to fight.  Clinton may be a shyster lawyer and a bitch,  but she isn’t manipulatable in that way by our enemies. 

Friday, July 29, 2016

Stuff You Normally Do Not Think About

There is a group of voters that Donald Trump has brought to the Republican party which has overwhelmed both the extremist-Christian / extremist-conservative (“tea party”) base,  and the “traditional” or “establishment” Republicans.  This is how he became the party nominee for 2016. 

The extremist-Christian / extremist-conservative groups had already overwhelmed the “traditional” or “establishment” Republicans enough to dominate party agenda for the last few elections.  But they,  in turn,  have been completely overwhelmed this year by the Trump supporters. 

So who are these Trump supporters?  It varies,  but largely they are working class and lower middle class folks who work in the trades.  They have been left behind economically by the Republican party,  which is largely in-hoc to giant corporation management,  but these Trump supporters have voted for Republicans generally because of “trickle-down economics” promises,  which have since proven to be lies. 

60+ years of being left behind economically have left them very angry,  and this anger actually extends to both parties (equally guilty).  Trump promises to do something to help them,  although his actual business record denies that he will. 

However,  you have to look very hard to find out about that discrepancy,  which is something non-college-educated folks seldom do.  And that is how Trump won the Republican nomination:  he tells the “conservative” left-behinds what they want to hear,  and they look no further.  They outnumber the rest of the entire party.

The Other Side

 There is also a group of relatively-strident voters that Bernie Sanders has brought to the Democratic party.  They are a considerable plurality,  or Sanders would not have come anywhere near as close as he did to being the nominee.  And he did. 

A plurality that large must be taken very seriously,  and I think the Democrats-as-a-whole did,  when adopting their platform.   Even so,  Hillary Clinton has become the Democratic nominee for 2016.  But,  a lot of the issues addressed in her acceptance speech actually came from the Sanders campaign. 

So who are these Sanders supporters?  A coalition of multiple groups,  actually.  One group is non-college-educated working class people left behind by both parties for 60+ years,  exactly like the Trump supporters,  except for opposite political leanings.  They are very angry,  at both parties. 

Another group is college-educated middle class people also left behind by both parties for 60+ years.  These are somewhat-similar to the Trump supporters,  but have opposite political leanings.  They are also angry at both parties. 

Most of the rest are college-educated and relatively-young (under-30) folks.  There are some older folks who also like what Senator Sanders had to say.  Most of these folks are not “angry” so much as just looking for real change. 

Net Effect from Both Sides

All share a problem with being left behind economically for 60+ years.  That’s the common element among them all,  whether Trump or Sanders supporters. 

Here’s the funny part,  if it wasn’t so pathetic:  between the Trump supporters and the Bernie Sanders supporters,  they are a majority of the electorate.  If they could ditch the opposite-party political propaganda,  there’s enough of them to vote in the changes that would correct 60+ years of being left behind economically. 

How Did This Happen?

That being left behind comes from three dominant sources:  (1) improperly-regulated globalization,  (2) improperly-regulated automation,  and (3) the very richest entities not paying their fair share of taxes. 

Improperly-regulated globalization sends jobs overseas to slave-labor economies,  because the short-term labor costs are lower.  Improperly-regulated automation reduces the number of properly-paying jobs at home,  because robots get paid no salaries or benefits.   Super-rich entities buy politicians in order to pay no taxes. 

Globalization:  this must happen,  but it demands proper regulation to avoid sending jobs overseas to the slave labor markets.  This is a moral imperative,  because slavery anywhere is wrong.  Simple as that. 

If the overseas job is a slave labor job,  then there needs to be a real economic disadvantage to sending that work overseas to that slave labor market.  The first thing that comes to mind is far bigger taxes when outsourced jobs go to slave labor. 

Automation:  this will happen,  but it doesn’t need to be as cheap as it currently is.  This again is a moral imperative,  and a constitutional imperative in the United States! 

The way automation currently happens in this country,  a large number of manual labor jobs are eliminated in favor of a very few robot-supervision / maintenance jobs.  So how is allowing net job elimination for enhanced profit in accord with “promoting the general welfare”,  as the constitution has it? 

Just what in hell are all 330 million of us supposed to do for a living?  Our government is supposed to be managing that question “for the general welfare”,  and obviously has not.  Not since at least WW2.

Tax avoidance by the richest:  if you can buy enough representatives and senators their jobs,  they will write laws for you that enable you to avoid paying taxes.  Only the real giants can afford to do this really effectively,  so there is a spectrum of tax avoidance effects that completely leaves out small businesses and individuals.  Again,  how is that fair?  Or in accord with the constitution?

My Conclusions

Yet,  there is nothing surprising about that outcome.  We have allowed it to happen since the founding of the Republic by allowing lobbyist monies in government.  This has been going on “big time” since WW2. To end it,  all lobbyist monies must be outlawed.  It’s really that simple.

Why have these three problems been going on for so long?  In a word,  money talks far too loudly in the halls of our government.  That’s both elected officials who work for whoever bought their jobs for them (not we who elected them),  and appointed officials who get rich the same way.

They follow the money. 

Fix that,  and a lot of our problems go away. 

Update 8-4-16:

There are some related articles elsewhere on this site,  one of which seems to be modestly popular with readers (the 7-29-16 article).  Another one is just a funny (the 4-24-16 article).  All share the search keyword “idiocy in politics”.  Here’s the list:

8-4-16….Evaluation of Choices for 2016
7-29-16…..Stuff You Normally Do Not Think About  (this one)
6-5-16…….Trump?  NO!!
4-24-16….Better Choices in November
12-21-15..Facts Must Trump Politics

Tuesday, June 21, 2016

What the Gun Violence Data Really Say

Update 7-9-16:  It is too early to have the facts about the mass shooting of police officers in Dallas.  My hunch is that extremized politics-of-race and more-than-a-little-craziness both played roles.  We'll see,  soon enough.  When we do know,  I'll add it to the database.

Meanwhile,  my article stands,  just as it is,  just below.  I do not see sanity in spending the effort and resources doing things that demonstrably produce little or no benefit.  I prefer to consult the actual data for suggestions as to what might produce large beneficial effects.

Update 7-14-16:  Preliminary data suggest my hunch was exactly correct.


Every time there is a mass shooting incident,  there are calls for stricter gun control,  and disappointment when nothing effective is done.  Few agree on exactly what to do. 

This time is no different:  the Senate just voted down 4 proposed gun control bills offered only days after the Orlando bar incident.  As well they should,  nothing effective or fair could possibly be worked out that quickly.  Better no change than the wrong one,  because they are so hard to undo. 

If one gets control of one’s emotions and takes a very hard look at the data,  one can easily see that most gun control proposals beyond what we already have in place would be quite ineffective.  In point of fact,  places where access to firearms is very restricted actually have higher rates of violent crime.  That is because the “bad guys”,  who scoff at laws restricting access to weapons,  enjoy a plethora of sitting-duck targets in those venues.  So,  too,  do the terrorists in Europe. 

The Real Data

I found an excellent database of US mass shooting incidents available from as a downloadable spreadsheet,  which goes back 3 decades.  It is too large to republish here,  so I abstracted from it the bare essentials of all incidents with a 10 or more death toll,  plus two other incidents that didn’t have that high a death toll,  but are nonetheless infamous. 

I added to my short list whether or not religious or political extremism played a role.  I specifically included whether the shooter was known to have mental problems,  although sometimes this took looking through the detailed notes to determine this.  The motherjones data included whether the weapons were obtained legally or not. 

I did not include weapon type:  most were semi-automatic.   Only some were so-called “assault” weapons,  some were not even semi-automatic. 

The short list data follows.  I highlighted yellow the cases where the shooter was known to be crazy and still got weapons legally.  I highlighted green those few cases where a religious or political extremist got their guns legally.  I highlighted orange those cases where the incident took place in an undefended gun-free zone. 


If you follow the highlight colors,  the proper responses jump right off the page at you.   They have little to do with most gun control proposals.  Truth may be painful,  but it sets you free. 

We have a serious mental issues leak in our background check system,   as the yellow highlights indicate so very clearly.  People known beforehand to have mental problems are getting guns legally.  This is because the background check is a go/no-go gate based a court judgment of insanity. 

None of these shooters met that standard.  Fix that,  and half the incidents in the table go away.  That’s worth the effort to address. 

How about a tiered response,  where unease on the part of the seller triggers a real investigation by a real law enforcement person,  and not just a paper records search for a court judgment?  Columbine,  and Red Lake,   might have been prevented by that.  Probably not Newtown,  where the shooter killed his own mother to get her guns for his spree. 

Religious and political extremism is starting to come to America.  That’s the two green highlights in the table.  This is what Senator Cornyn’s FBI watch list proposal (that was voted down) was intended to address.  This isn’t a big problem yet,  but if Europe is a guide,  it will be,  soon. 

The orange highlighting shows the dominant problem,  the one nobody wants to face.  That is the inadequately-defended gun free zone,  the sitting-duck target.  This is the common element in nearly every single incident,  regardless of whether caused by mental issues or extremism.   The two exceptions not highlighted are government facilities,  but it was unclear to me whether those areas were actually open to the public. 

My point is that if these victims hadn’t been sitting ducks,  they probably would be alive today.  The lesson is quite clear:  gun free zones (and there are good reasons to have them) must be defended. 

The Most Important Recommendations

What constitutes an adequately and properly defended gun free zone has been known since the 19th century American frontier towns.  There are only two requirements:  (1) you need a properly trained peace officer as your guard,  and (2) he must be able to respond within about 60 seconds. 

About requirement (1):   anyone called upon to defend a gun-free zone against attackers will have to do the job of a peace officer.  Therefore peace officer training is required.  Concealed-carry training is not peace officer training.  Period.

About requirement (2):  this was demonstrated in frontier towns that went gun-free,  for over 50 years.  Those were small towns geographically:  a deputy at a dog trot could reach anywhere in town in 60 seconds or less.  When the towns grew,  longer response proved inadequate:  more died. 

What that means today is twofold:  (1) you need one or more guards qualified as peace officers on your gun-free zone site,  and (2) these guards must be able to reach anywhere in the site within 60 seconds.  I doubt we need any federal laws about how exactly to do this,  that should be determined locally,  since every region is different.  But those two broad requirements could usefully be federal. 

Popular knee-jerk things like clip size limits and “assault” weapon bans won’t do any significant good.  A tiered response to mental issues,  and a proper defense of gun-free zones would obviously do a lot of good right now.  Using the FBI watch list to slow-up gun acquisition by the amateur class of religious or political extremists might soon be something that could help,  although real terrorists will get them illegally,  just like real criminals.

But if you defend your gun-free zones,  the terrorists will have to look for other targets!  That's the big effect here.  

About Weapon Types

I didn’t include weapon types in my abstracted data.  Most of these were semi-automatic weapons,  some of those the so-called “assault” weapons like the AR-15.  A few were not even semi-automatic. 

Semi-automatic is a World War 2 technology (M-1 Garand and M-1 Carbine).  No modern soldier would live long in battle with an AR-15 instead of the fully-automatic look-alike M-16 (a real machine gun). 

Calling semi-automatic weapons “assault weapons” just because they resemble machine guns is nonsense,  and usually indicates either a gun control political agenda or utter ignorance about firearms. 

Conclusion (as an update 7-4-16):

I offer these things which might actually help (dealing with the mental issues background check leak and the sitting-duck undefended gun free zones) as truly data-driven,  and therefore very probably worthwhile to do.

Most of the other knee-jerk proposals are demonstrably ineffective at best,  and we know this,  because we've already tried them.  Why waste the effort to do them again?

Spend your effort and your resources on something that might actually work,  to do otherwise is insanely stupid.  

Gun Articles as of 6-21-16 (this one highlighted):
6-21-16 What the Gun Violence Data Really Say 
10-7-15 Oregon Mass Shooting and Gun Control
5-31-14 On Calls for More Gun Control
10-1-13 Government Shutdown,  Default!  Again?  No!!!
9-20-13 More Gun Control?  No Way!
2-5-13 Real Problems with the Proposed Gun Control Legislation Items
12-20-12 On the Tragedy in Connecticut
12-14-12 School Shooting in Connecticut
8-9-12 Mass Murder Shooters and Gun Control
1-13-11 On the Shooting Rampage in Tucson

Sunday, June 5, 2016

Trump? NO!!

Update 11-15-16:

Well,  it looks like I may get my wish that was expressed below. Tammy Duckworth will be an incoming US senator.  Sooner or later,  she and Trump or his admin figures will cross swords over something stupid.  --  GW


This from our local paper about Donald Trump:
In a 1997 interview with radio disc jockey Howard Stern, Trump, who used student deferments and a “heel spur” medical deferment to get out of military service during the Vietnam War, said the danger he faced from getting sexually transmitted diseases when he was sleeping around in the United States was his own “personal Vietnam.”
“I’ve been so lucky in terms of that whole world. It is a dangerous world out there. It’s scary like Vietnam. Sort of like the Vietnam era,” he said. “It is my personal Vietnam. I feel like a great and very brave soldier.”


I'd like to see what US Rep. Tammy Duckworth would say to Trump about this egregious statement he made.  She very effectively took another congressman down,  right there on the floor of the House,  for saying something similarly stupid.  

For those who do not know,  Tammy Duckworth was a 1991 Gulf War vet who lost both legs in the explosion,  when the helicopter she was flying was shot down with a rocket-propelled grenade.  


Although my own service time was short and I never went to Southeast Asia,  I did join up during Vietnam.  Even with my limited service,  I find Trump’s comments EXTREMELY OFFENSIVE.  Offensive and egregiously stupid.  That man has no business commanding anything,  much less US military personnel. 



Update 6-12-16:  What this shows is a longstanding pattern with Trump.  19 years,  at least.  He will not change.  He is clearly unsuited to be commander-in-chief.  

Update 7-27-16:  Today Trump publicly appealed to (state-supported) Russian hackers to uncover the missing Clinton state department emails.  Considering the bad state of affairs between the US and Russia,  due largely to Putin's ambitions for a new Russian empire,  this is borderline treason on Trump's part.  

"Aid and comfort to the enemy" with 6+ witnesses,  per the definition.  Putin wants Trump to win and hates Clinton.  He is trying to sway our election for his own purposes by releasing hacked Clinton files.  I really do not like that.  And I really hate the prospect of a president the Russians can influence so easily to their own ends.  

Update 8-4-16:

There are some related articles elsewhere on this site,  one of which seems to be modestly popular with readers (the 7-29-16 article).  Another one is just a funny (the 4-24-16 article).  All share the search keyword “idiocy in politics”.  Here’s the list:

8-4-16.....Evaluation of Choices for 2016
7-29-16…..Stuff You Normally Do Not Think About
6-5-16…….Trump?  NO!!   (this one)
4-24-16….Better Choices in November
12-21-15..Facts Must Trump Politics

Saturday, May 28, 2016

Mars Mission Outline 2016

Update 5-30-16:  this article culminates about 6 years' efforts looking at manned Mars mission ideas.  There are several other related earlier articles about men to Mars on this site,  but this one is by far the best.  It does reference the lander study article below:  "Reusable Chemical Mars Landing Boats Are Feasible",  dated 8-31-2013.  

It was from that lander study article that I drew out my results for the NTO-hydrazine blend lander as the one compatible with the same long-term storable fuel used here to push the orbit-to-orbit manned transport.  That allows fuel allocations to fit conditions without changing hardware.  

The big difference with this study is the huge reductions in launched masses and costs that I saw by sending the unmanned stuff "slowboat" ahead with electric propulsion.  But,  if I did that with the manned portion,  it would turn a 2.5 year trip into a 3.3 year trip for the astronauts,  so I did not do that.  

Update 5-31-16:  corrections to the radiation formula and some typos below,  in red.  


It should be possible to send six people to the surface of Mars with current technology and very-near-term ready-able hardware,  for under $50 billion,  and get them back in good health.  This can be done while recovering the manned spacecraft in Earth orbit for reuse on other missions.  Typical claims by industry giants and NASA itself that this cannot be done for under half a trillion dollars are nonsense.

Mission Architecture

I used the 1950’s orbit-to-orbit transport concept for the manned portion.  The inspiration was an item in the 1957 Disney “Tomorrowland” film “Mars and Beyond”.   That concept was a fleet of nuclear-powered ion thruster-propelled ships built in Earth orbit.  These traveled to Mars orbit,  where they sent chemical rocket-powered landers to the surface.  They returned for recovery (and presumably re-use) in Earth orbit.  There being six ships,  each with a lander rocket,  up to six different sites could be explored at Mars.  See Figure 1 for two illustrations from the Disney film.  

The actual technologies depicted are obsolete or otherwise in error.   But,  the key concepts are still valid,  so I used them.  These were :  (1) the orbit-to-orbit transport,   (2) separate landers,  (3) ability to visit multiple sites,  and (4) recovery and reuse of essential hardware.

Figure 1 –6-Ship Exploration Fleet,  from Disney’s 1957 film “Mars and Beyond”

The orbit-to-orbit transport vehicle serves only to transport the crew safely both ways,  and to house those not on the surface safely while in Mars orbit.  It comprises a spacious “deep space habitat” plus a crew return capsule plus suitable engines that burn long-term storable propellants for arrival at Mars (nitrogen tetroxide and a hydrazine blend).  It departs with a liquid hydrogen/liquid oxygen departure stage,  then spins for artificial gravity during a Hohmann min energy transfer orbit (the minimum practical flight time of 8-9 months at minimum expended energy).  It returns to Earth using all storable propellants sent ahead to Mars orbit.  The crew of six lives in the habitat,  not the capsule,  for this trip. 

Landers,  their propellant supply,  and the Earth return propellants for the manned vehicle are sent ahead to low Mars orbit,  where the manned vehicle must rendezvous with them.  These unmanned vehicles are sent by solar electric propulsion on longer transits that spiral-out and spiral-in.  The electric propulsion does save enormous amounts of weights and costs,  but adds months to the trip time. 

The landers are single stage re-usable chemical vehicles,  whose crewed control cabin doubles as an abort capsule capable of getting the crew to the surface from anywhere along the descent or ascent trajectories,  from orbit,  but not to orbit,  from the surface.  To provide rescue for a stranded crew,  three landers are sent as fully-fueled items,  plus extra lander propellant to support repeat trips.  That gives a rescue capability even if one lander fails,  or is otherwise lost,  for any reason at all.  The current concept uses the same storable propellants as the manned vehicle. 

The lander is the sole item to be developed “from scratch”,  and may require assembly in Earth orbit.  It is “the long pole in the tent”,  and will pace the program.  It has no new technologies,  but this combination has not been tried before.  The rest is a reshaping or re-sizing of things we already build. 

The trip to and from Mars is about 8-9 months long (one-way) for the manned vehicle,  with roughly a year in orbit at Mars.  This is thus about a 2.5 year mission for the crew,  which does not launch until the supplies are verified as sent ahead successfully to Mars orbit.  While in orbit,  three crew take a lander to the surface for up to a 30-day stay,  while the other three crew do science from orbit,  and provide the rescue capability with the other landers.  This process repeats,  alternating surface crews,  for up to eight landings,  without compromising the rescue capability.  Spin gravity is maintained in Mars orbit. 

Earth return propellant is also sent ahead to Mars orbit with solar electric propulsion,  like the landers and their supplies.  The manned vehicle discards empties,  then docks with the return propellant tanks.  Once Mars departure is complete,  those tanks are staged away,  and the vehicle spun-up for gravity during the voyage home.  The last of the propellant is used to enter Earth orbit,  so that the vehicle can be recovered,  refitted,  and reused,  on other missions (unique among the mission plans I have seen in recent decades).  The crew finally returns home in the attached capsule,  which is rated for a full free-return “emergency bailout” reentry,  in the event that vehicle propulsion should fail approaching Earth. 

Assets left in Mars orbit are the three landers,  plus the empty Mars arrival and lander propellant tanks,  and the four depleted solar electric transfer stages (for the Earth return propellants and for the three landers and their propellants).  With a little extra ion propellant,  these electric propulsion stages could be brought home,  too.  It is probably wise to leave the landers in Mars orbit,  for future re-use,  with more propellants either brought from Earth,  or manufactured on Mars,  or both. 

Propellant Selections

For the manned vehicle and the landers,  I chose nitrogen tetroxide and a hydrazine blend at a very conservative 300 sec specific impulse,  precisely because it is very long-term storable in space without any boiloff risks.  This simplifies propellant tank designs,  enabling the practical achievement of very low tank inert mass fractions,  something fundamentally not possible with insulated and sun-shielded Dewars for cryogenics.  I used the same for the landers,  except at a more realistic 317 seconds of specific impulse for a modest chamber pressure and slight cant angle reduction. 

For the electric propulsion stages,  current ion thrusters usually use xenon,  but I would encourage the use of argon instead,  as far more widely available.  Both are noble gases,  and either should work just fine.  The stage inert weights I used include large solar electric panels.  I assumed 5000 sec specific impulse for these,  which should also be conservative. 

For the Earth departure stage (of the manned vehicle),  I chose liquid hydrogen-liquid oxygen at about 465 seconds of specific impulse (rather realistic).  I chose it for the performance in spite of the boiloff risks.  This item is conceived as the last thing to be sent up and docked to the manned vehicle,  at about the same time as the crew arrives.  It may have to be sent up in multiple pieces and docked together in orbit,  but the boiloff risk is only days long,  not months or years. 

Trip Requirements

The delta-vee requirements from Earth orbit to Mars orbit depend upon whether Mars is a little nearer or farther away at opposition.  To be conservative,  I used the maximum Earth departure delta-vee of 3.8 km/sec,  and the maximum Mars arrival delta-vee of 2.4 km/s,  even though these numbers “do not go together”.  That’s 6.2 km/s one-way,  and 12.4 km/s two-way,  even though the largest two-way delta-vee is really just 11.9 km/s.  A “real” design will therefore be much better than depicted here,  especially since I used such a low conservative value for specific impulse,  too.    

For the solar electric propulsion,  as a rule-of-thumb,  I simply doubled the delta-vee requirements to account for the gravity losses of long-duration non-impulsive “burns”.  It wouldn’t make very much difference to triple the delta-vee,  due to the high specific impulse available with ion thrusters. 

The Deep Space Habitat:  Source Technology

For this,  I assumed the characteristics of the Bigelow B330 inflatable module,  which in fact is based upon NASA’s own design characteristics for a deep space habitat.  The habitat uses two of the modified B330 modules.  The difference are:   (1) I assumed heavier mass to account for strengthening the modules for higher applied loads,  and (2) I spin the assembly for artificial gravity (why the extra strength is needed). 

To this I add one custom “hard” module in the center,  that has electrically-powered spin-up flywheels,  an airlock,  and some docking ports.  Any solar panels should attach here as well,  being near the spin center for low acceleration loads.  (We have already built similar modules for the space station.) 

The basic characteristics of the B330 module are given in Figure 2.  This is the item to be launched by Bigelow Aerospace about 2020 via the ULA Atlas-5 booster,  as a zero-gee space station.  It has an enormous interior volume for a very modest mass,  as compared to all the hard modules used to construct the international space station.  These take the form of a folded inflatable packed about a cylindrical hard core,  with docking hardware  at each end.  The inflatable has many layers,  considerable wall thickness (nearly half a meter),  and thus considerable meteoroid-impact protection.  Multiple modules docked together can make a really voluminous space station very quickly.  

Figure 2 – Characteristics of the B330 Inflatable Module,  Current as of May 2016

The Deep Space Habitat:  Size and Spin Rate

It is weightlessness that induces a myriad of microgravity diseases in the human body.  Not everything we need to know is yet known,  but we know enough to know that beyond just a little over a year’s exposure,   the effects become harder and harder to reverse,  if not actually impossible.  That’s not long enough to go anywhere beyond the moon.  Which says you do artificial gravity,  no if’s,  and’s,  or but’s

It is reasonable to suppose that reduced gravity might be somewhat therapeutic,  but we absolutely do not know how much is enough,  because those experiments have never been run directly.  So,  for a long mission in the 2-3 year range,  the only ethical decision at this time in history is to provide one full gee of artificial gravity.  The only method known to science is spin gravity:  using centrifugal force as a substitute for the force of gravity.   General relativity tells us they are fundamentally equivalent. 

How much gravity you get depends upon your radius away from the spin enter,  and upon the square of your spin rate.  Science tells us that 56 m radius at 4 rpm is one full gee at that radius.  Assuming your spin center (center of gravity) is in the middle of your design,  then your radius is about half the length of your design,  if you use a baton-shaped design spinning end-over-end.  This configuration is very stable in spin,  as all of us have seen in Friday night football game half-time shows.  You can ratio-and-proportion this from:

     Gees at radius = (your radius, m / 56 m)*(your spin rate, rpm / 4 rpm)2

Now,  untrained civilians easily tolerate 3-4 rpm spin rates without getting sick.  Well-trained crews with plenty of time to acclimate,  can tolerate something in the vicinity of 12 rpm long-term,  without getting sick.  Down around 7-8 rpm,  almost anybody should be trainable,  and acclimatize well,  fairly quickly. 

There is a gravity gradient effect on blood pressure gradients and fainting that is also proportional to spin rate,  but it should “kick in” nearer 16-20 rpm.  That’s no problem,  if we stay under 12 rpm anyway. 

I chose to consider either two or four somewhat-modified B330 modules with a center “hard” module,  for spinning space stations with artificial gravity.  These are illustrated in Figure 3 below,  and have 1 gee at the outer deck,  less inward,  to zero at the spin center.  Dimensions of the center module are not yet “hard”;  that one still needs to be designed.  It has electrically-powered spin-up flywheels,  an airlock,  and more than one docking port,  plus the best locations for attaching solar panels. 

Arranging the Interior

I would point out that the bed rest studies used on Earth as a surrogate for microgravity are as applicable as they are,  precisely because the body does not benefit from gravity while prone sleeping.  What that says is that you put your daily work shift stations at or near the one-gee level in a spin gravity design,  where being seated or standing provides the same beneficial effects as experienced at home. 

You may put sleeping quarters nearest the spin center at very -low-to-zero gee,  as there is no benefit from gravity while sleeping here,  there or at home. 

The off-duty and recreational functions can be put somewhere in between at the reduced gravity levels.  Thus the crew can benefit from whatever benefits there are from partial gravity,  during waking hours,  and under circumstances that actually could be fun. 

These same spinning space station design layout considerations also apply to the manned orbit-to-orbit transport version.  It is essentially a suitably-modified spin gravity space station design.

Figure 3 – Possible Variations on the B330 to Create a Space Station with Artificial Gravity

What we see with the three-module form is a space station of about 700 cubic meters internal volume and about 65 tons mass,  spinning at around 6-7 rpm,  tolerable with modest training.  This thing could be easily constructed by docking things sent to Earth orbit with current launch rockets.  The 700 cubic meters is almost as big as the entire international space station habitable volume,  as we know it today.  Unlike the current station,  this design allows us to directly explore the therapeutic value of partial gee levels.  And it would be far cheaper to build! 

The five-module form would be a little more expensive to build at 115 tons,  but would be far,  far larger than the current station in internal volume at about 1800 cubic meters.  Its lower 5 rpm spin rate is likely tolerable,  even by untrained civilians,  with only a few days’ acclimatization. 

What does artificial gravity buy you for a space station or an interplanetary spacecraft? 

It buys you freedom from the time limited exposure to microgravity,  with respect to microgravity diseases.  These include at least bone loss,  muscle weakness,  heart degradation,  bad vision effects,  and reduced immune system response. 

It buys you a much wider choice of food selection and cooking methods,  which now look just like they do down here.  It buys you food that will last a full 2-3 years,  or more,  in space without deterioration, by means of enabling frozen food and free-surface water-based cooking.  The current freeze-dried items last only a little more than a year!  Astronaut “food” is literally not sufficient for going to Mars!

It buys you “conventional”,  well-understood means of handling water and wastewater processing.  It buys you “conventional” easier-to-use toilets.  It buys you the ability to do laundry (currently impossible in weightlessness).  It buys you the possibility of conventional tub and shower bathing (also currently impossible in weightlessness). 

For missions in the 2-3 year range,  all these functions are essential to keeping a sane,  healthy crew!

We can equip and plan for a few days weightless as things get docked,  and as the vehicle makes maneuvering burns.  Between these short intervals,  it is imperative to spin-up for gravity to maintain health and fitness.  Electrically-powered flywheels would serve that function very well. 

What I chose for the Mars vehicle design was the lighter 3-module form,  to save exponentially on launched mass in Earth orbit,  which in turn seems to drive estimated program cost. 

The Other Crew Health Issues: Radiation

There are two different kinds of space radiation: galactic cosmic rays (GCR) and solar flare events (SFE).   The GCR is a very slow drizzle of extremely high-energy subatomic particles,  which are very difficult to shield.  This is because of “secondary shower” effects:  GCR particles hitting your shielding create a whole shower of other dangerous particles.  The thicker your shielding,  the worse this is,  in any practical geometries.  Near-Earth GCR intensity varies with the solar activity cycle:

    GCR = 42 REM annual + (18 REM annual) sin (time, yrs/ 11 years)
    where time is measured from the time of minimum exposure value

GCR in the inner solar system near Earth peaks at about 60 REM in years when the sun is quiet,  and minimizes near 24 REM in years when the sun is very active with storms,  sunspots,  and flares.  Among other limitations,  NASA limits astronaut radiation exposure to 50 REM max annual,  based on an expected 3% increase in cancer rates late in life.  Bear in mind that this is a sharp line drawn upon an inherently very fuzzy spectrum of effects. 

When you are orbiting lose to an astronomical body,  such as Mars or the Earth,  the planet blocks roughly half the sky at a thickness dimension too big to allow the “secondary shower” effect to occur,  thus cutting exposures roughly in half.   Otherwise,  even a thin spacecraft hull acts to reduce the exposure a little bit,  and also without the “secondary shower” effect,  precisely because it is thin. 

As close as 50 REM annual allowable is to 60 REM annual in a peak year,  I have to conclude that GCR is simply not the threat that some hype it up to be.  Astronauts wanting to go to Mars (and I wanted to be one myself,  45+ years ago) unanimously agree.

Solar flare events (SFE) vary widely in strength and in the actual location they threaten.  These are far lower-energy particulate radiation,  easy to shield,  but are also extremely intense (quantity).  The worst on record happened in 1972 between two Apollo landings on the moon.  Had a crew been out there to be struck by such a thing,  they would have died within hours,  very much like standing outside unprotected in the fallout from a surface nuclear bomb blast.  It takes but 15-20 cm of water to shield against the worst known case,  according to NASA’s own data.  It is the hydrogen in the water (or any other substance) that provides the shielding effect. 

If you have humans on board,  you have life support,  which means you have water and wastewater on board.  If you have spin gravity,  it is very likely that you have frozen food aboard.  All three of these are very effective shielding materials against SFE.  Arrange 15 to 20 cm of these about a designated sheltering space,  and you have a good shelter in which to ride out the SFE,  which is typically only a few hours long.  The smart designer would make this the vehicle’s flight control station (cockpit),  so that critical mission maneuvers could be flownregardless of the solar weather.

The Other Crew Health Issue: Living Space

Living space is the other crew health issue often not adequately addressed.  This is far more than just a volume allotment per person,  because real people require spaces in which to be together,  and other spaces in which to be alone.  But volume-per-person is a figure of merit we can compare.  You can ask anyone who has ever served prison time in solitary confinement how important this is.  He will verify that what we are doing now on the space station for 6-month-to-a-year tours is inadequate for multiple years’-long confinement

Putting 6 crew into 700 cubic meters is over 100 cubic meters per person in my mission plan.  That’s about the same as the old 1970’s Skylab station,  larger than anything since except the latest ISS.  The trick is allocating this into communal versus private spaces.  I have not addressed that in detail here. 

The 1960’s Gemini 7 mission was “up there” for two weeks “doing it in the suit” from a sewage standpoint,  and without even the ability to straighten the knees in such a cramped capsule!  They (NASA) do not want you to know that the plan was originally a 3 week mission!  This crew was brought home at 2 weeks,  because they were literally cracking-up mentally.  You really have to dig hard to find that fact;  it is something NASA really does not want you to know

Why?  Because if you did know,  then you would also know that NASA’s publicity claims that its new Orion capsule is an “interplanetary travel vehicle” are not true.  It is only adequate for short trips,  such as to,  or near,  the moon.  Longer trips simply require a very much larger space in which to live. 

That 1960’s Gemini 7 mission was astronauts Frank Borman and Jim Lovell,  who later flew around the moon on Apollo 8;  and Lovell was commander of Apollo 13.  As Gemini 7,  they rendezvoused in orbit with Gemini 6,  up there only a very few days.  That 2 weeks-in-space demonstration was “enough” for the moon in a cramped capsule,  knowing that sewage bags would be available for waste disposal. 

It is 8 or 9 months one-way to Mars.  See the problem?

The Mission:  Getting Men There Without Landing

What I assumed was the 3-module 65 ton spin-gravity space station as the deep space habitat for my manned orbit-to-orbit transport,  with a crew of 6.  This thing is illustrated in Figure 4.  It depends upon Earth return propellant previously sent separately to Mars orbit.  I assumed 65 tons for the basic station,  plus 50 tons of supplies to support the crew,  plus a ton for some engines for arrival at Mars. It leaves Earth orbit coupled to the Mars-arrival tanks laterally,  and to an Earth orbit departure stage on one end.  After the departure burn,  this departure stage is jettisoned,  and the habitat spun up. 

The water/wastewater tanks are arranged as radiation shielding about one inflatable module,  with the hydrazine/tetroxide engines fitted to the other.  Mars arrival propellant tanks are arranged about both inflatables as additional shielding.  I assumed that 7.5 tons of the 50 tons of supplies would be consumed and jettisoned during transit to Mars.

 Figure 4 – Orbit Transport and Other Assets for Men to Mars Orbit,  Without Addressing the Landing

I further assumed that about 10 tons of the supplies would be consumed and jettisoned during the year-long stay in Mars orbit.  This lightens the mass to be accelerated home out of Mars orbit,  thus lowering return propellant required.  This effect is exponential in its impact (mass ratio in the rocket equation).

I also assumed a further 7.5 tons of life support mass would be consumed and jettisoned during the voyage home,  thus further reducing the dead-head mass to be decelerated into Earth orbit at the conclusion of the mission.  This actually made a big difference to launched propellant tank tonnage,  so fully-closed-cycle life support may actually not be the thing we need to strive for,  at this time in history!   

Perhaps my assumptions are not good enough,  but the beneficial mass-reduction effects are quite real. To summarize my assumptions:  (1) 50 tons of all life support and consumables initially,  (2) half of this mass gets used up and wastes jettisoned during the entire mission,  (3) 40% of the jettisoned waste mass happens during the roughly-a-year in Mars orbit,  and (4) the other 60% is split equally between the two 8-9 month transits.  Half the 50 ton life support mass is still aboard upon arrival at Earth orbit. 

Off-Design Crew Return with Loss of Vehicle

The mass allotment for the orbit-to-orbit transport does include about 6 tons for the crew return capsule.  This would be used to return six people to Earth from Earth orbit,  in the nominal case.  But if there were to be a complete propulsion failure before Earth arrival,  the crew would have to “bail out” in this capsule for a free return entry situation.  What that means is we need a capsule heat shield capable of 50,000+ fps (17 km/s) reentry speeds,  and large enough for a crew of 6. 

The Orion and the Boeing CST-100 Starliner are not capable of 50,000 fps (17 km/s) reentry,  only 36,000 fps  (11 km/s) from the moon for Orion,  and 25,000 fps (8 km/s) from Earth orbit for the CST-100.  Both are capable of 7 crew.  Orion is really heavy,  the CST-100 not so much. 

Only the Spacex Dragon v2 is capable of 7 crew plus 50,000+ fps reentry speeds.  That is the one I selected to use in my model here.  It (and only it) makes a 6 ton allowance “reasonable”,  if we delete the service module (unnecessary for this application). 

Sending Men to Mars Excluding Landers

There are two items that must be sent to accomplish this:  the manned vehicle,  and its return propellant. To do only this implies no landings at all.  As far as I am concerned,  as difficult as it is to get men to Mars and back at this time in history,  not-to -land is equivalent to Columbus looking over the rail at the New World,  and sailing back to Spain without landing.  That would clearly have been the height of stupidity in Columbus’s day,  just as going to Mars without landing is today. 

Regardless,  you send two clusters to Mars orbit in order to send men there,  with the technologies that we have.  You send the manned habitat as quickly as you can,  and you send its return propellant “slowboat” with electric propulsion,  before you ever send the men.  This same approach would work with Venus or any of the asteroids, or even Mercury. 

For Mars and Mercury,  you need landers to complete the task.  Landers for those two destinations are necessarily very different.  The lander for each destination is thus a custom design. 

The results of my analysis are as follows.  The manned vessel at departure from Earth orbit is on the order of 50 m long,  and about 760 metric tons at departure ignition.  It cannot come home unless you send ahead its Earth return propellant.  That’s about 937 tons of storable-propellant tanks,  sent ahead with a solar electric stage for both the departure and arrival “burns”.   That propellant shipment vehicle is somewhere in the vicinity of 1245 metric tons at Earth orbit departure.  None of these are small,  but they are not “battlestar galactica”,  either.

Sending Landers for Mars

In order to make the journey worthwhile at allwe have to land.  One-way / one-shot landers can do this at much higher payload fraction and lower ignition weight,  but with a very limited number of trips (one per lander).  If instead you design for a two-way,  one-stage trip,  you can actually fly the vehicle multiple times:  several trips per lander. 

Because of the multiple trip effect, in spite of its far lower payload fraction (near 3% max),  with the reusable lander approach you can raise the “bang for the buck” far above anything the one-shot throwaway approach offers.  This is indeed feasible today with a variety of propellant combinations.  I chose the same nitrogen tetroxide-monomethyl hydrazine as I chose for the manned vehicle,  precisely because it is easily storable at low inert mass fraction,  in space,  for years. 

Reusable lander design is another whole design study in itself.  I had previously done one to confirm that a chemically-powered single stage two-way lander was indeed feasible at all,  for four different propellant combinations.  Suffice it to say that my version uses retropropulsive landing after the entry hypersonics at Mars,  to avoid the high-ballistic coefficient difficulties with aero-deceleration by chutes.  The total delta-vee (two way) is on the order of 4.5 km/s.  That’s 3.6 for ascent,  and 0.9 for the retropulsive deceleration-to-touchdown. 

In that study,  my paper lander designs show enough delta-vee to land just over 3 metric tons of astronauts plus gear on Mars’s surface,  for a stay of up to 30 days.  The idea is to live in the lander itself,  but to travel around the landing site in a small,  drill rig-equipped,  rover.  To support longer traverses,  a inflatable 3-man ”pup tent” is assumed  to be carried on that rover car.  In addition,  I included a payload allotment for 3 in-situ resource utilization experiments,  plus three “other” experiments,  for each trip to the surface.  “Camping out” in the lander for only 30 days completely eliminates the need for a large surface habitat on Mars.  That’s a huge launch mass savings,  and a huge entry descent and landing problem avoided. 

My choice of NTO-MMH leads to the largest,  least-capable lander design,  in terms of total delta-vee.  It’s about 90.7 metric tons ignition mass,  fueled for a trip to the surface and back.  Anything we really do should be better than this,  certainly no worse.   If we leave everything on the surface except the astronauts,  their suits,  and their transit consumables,  there is “room” to bring a fair fraction of a ton of surface samples and experiment results back to low Mars orbit. 

These craft take the form of a slope-sided early space capsule with a projecting neck,  scaled way up.  It is about 10 m long,  about 8 m diameter at the heat shield,  and has a 5 m diameter core.  These are approximate,  but in the lander feasibility study,  all 3 "conventional" propellant combinations were just about these sizes and proportions.  Only the hydrogen-oxygen "bird" was different.  

The internal layout has a cylindrical core of a sealed engine room,  plus tall propellant tankage,  surrounded by a conical volume for cargo spaces.  There is a spherical-segment heat shield,  with holes through which the four slightly-canted engines fire.  Because the engine compartment is sealed,  there is no entry plasma flow into the compartment through the holes for the engine plumes. 

It has retractable landing legs,  whose footprint is roughly as wide as the craft is tall.  That provides stability,  even on rough ground.  Shell panels fold down to act as loading ramps.  The cargo spaces can be sealed and pressurized for living space,  once unloaded.  The crew cabin atop the neck provides great piloting visibility.  If also built as an abort capsule,  then the crew of a stricken lander can “bail out” during descent or ascent,  and reach the surface alive to await rescue. 

Having that lander bail-out capability only makes sense if there is also rescue capability available in the mission designThat is primarily why I send 3 landers,  not just one.  If you have at least 2 operational landers,  then you can impose the wise safety rule that one lander be ready in orbit for a rescue trip while the other is on a mission to the surface.  You do not take the risk of a trip to the surface unless you have that rescue lander available.  But,  there is also always the risk that one “bird” might fail or otherwise become unusable.  In that case,  your surface missions end,  if you have only two.  So,  I send three.  That way the prime mission still proceeds,  even if one lander becomes unusable or is lost. 

You send down a lander with a crew of three,  while the other three do science from orbit,  watch over the surface crew,  and maintain peak fitness in the spin gravity environment.  When the surface crew returns,  they swap roles for the next trip to the surface.  See Figure 5. 

A rescue flight uses a crew of one only,  and does not stay down long.  You handle the weight of 4 people on ascent by offloading supplies and equipment to “lighten ship” for the rescue flight.

My plan here includes 3 landers,  sent fueled,  plus propellant to support two more trips for each lander.  That’s propellant for 9 total surface trips.  However,  only 8 trips can be made if you maintain rescue capability,  because you need that one fueled rescue lander in orbit at all times. 

Even so,  this mission plan and sizing provides up to 8 months on the surface of Mars,  in alternating crews of 3.  This can be at one site or it can be up to 8 sites (8 flights).  I would recommend visiting at least 7 different sites,  so that the “best” can be identified for installation of a base or permanent experiment station on the final sortie.  That’s a whole lot of “bang for the buck”more than I have seen in any of the one-site plans

These landers,  with their extra propellant tankage,  get sent as individual packages by means of electric propulsion,  as shown in Figure 6.  Of all the packages “flung” to Mars orbit,  these are individually the smallest at under 300 tons for 3 trips per lander.  The empty tanks,  landers,  and SEP stages all get left in Mars orbit at end of stay there.  With a little extra SEP propellant,  the SEP stages could be brought home to Earth orbit for reuse as well. 

There’s also room to add extra lander propellant,  of course.  For example,  using 5 trips per lander,  3 landers,  and the 1 rescue reserve,  that’s 14 trips available.  If spread over 13 months in orbit,  those average something like 27 days each.  It just costs more to launch and send it there.

Figure 5 – Use of Reusable Landers for Rescue Capability and Multi-Site Exploration Capability

 Figure 6 – Sending a Lander Ahead to Mars Orbit,  Along with Extra Propellant for Multiple Trips

Option to Establish a Permanent Automated Facility

There is an additional option here,  with respect to establishing a base or experiment station on that first manned mission to Mars.  The equipment to do this could be shipped inside one of the landers as an overload cargo item (because the space is available).  This is the third,  or back-up,  lander.  If the best site is determined in 7 visits,  and three landers are still flyable, then the ascent propellant can be off-loaded from this third lander,  with several tons of base equipment substituted inside it,  instead.  It can then be sent one-way to the surface at that best site,  using a crew of one,  who can ride with the three surface crew back to orbit in their lander. 

Some sort of homing guidance will be required to safely land two vehicles at one site,  though.  That will need to be part of the weight allowance for the equipment sent to the surface,  and may involve some small navigation aids in orbit as well.  Thus this option requires precision landing. Everything else about this plan is one vehicle at each one site.  The site need only be where the vehicle actually sets down.  

Another possibility is to send that lander down one-way robotically,  after all the crew has returned to orbit.  This would require equipment that operates entirely without human intervention,  and from within the lander’s cargo bay.  But the option inherently exists.  It requires precision landing guidance.

The real point is this:  there are ways to establish that permanent facility on Mars,  during the very first manned mission there,  and not “break the bank” doing it.  The enabling factors that create this opportunity are specifically (1) the on-orbit “basing” assumed in this mission plan,  and (2) the larger reusable lander vehicle design.  Other mission architectures without these specific features simply do not possess this possibility. 

Returning the Crew Safely to Earth

At end of mission on Mars,  with all crew safely aboard the orbit-to-orbit transport vehicle,  preparations begin for the trip home.  The vehicle is de-spun for a few days to dock up with the return propellant supplies. 

There are two groups of these:  (1) the Earth arrival tanks,  which are docked alongside the habitat modules to “fatten” the baton,  and (2) the Mars departure tanks,  docked to the end opposite the engines.  Docking implies propellant connections,  of course.  These connections likely will require astronauts on spacewalks to do them. 

Once ready,  the engines fire to leave Mars orbit.  Once the burn is complete,  those tanks are staged off,  and the vehicle spun-up for artificial gravity during the 8-9 month transit home.  A normal arrival at Earth requires a braking burn with the last of the propellant tanks.  This is depicted in Figure 7.  The crew returns from Earth orbit in the capsule,  at something like a 4 gee ride or thereabouts.  The vehicle itself can be refitted and used again on subsequent missions,  another huge “more bang for the buck” item. 

An abnormal arrival at Earth would occur if vehicle propulsion capability is lost.  In that event,  the crew must “bail out” in the Earth return capsule,  for a free-return entry at above escape speed.  That is likely a 12-15 gee event,  which is why maximum crew health from spin gravity is so essential.   A crew weakened by 2.5 years exposure to zero or low gravity would very likely not survive this much stress. 

That is also why the crew return capsule needs a heat shield capable of free-return entry,  even though such a return is not in the normal mission outline.  It is an emergency contingency only,  but ethics requires we plan for this properly.  

 Figure 7 – Returning a Healthy Crew to Earth

Providing Redundancy for Mission-Critical Propulsion Events

Loss of functionality of a rocket engine is a critical event,  since there are so many propulsive events required to make this trip.  Thus,  I use multiple engines for each propulsion installation.  The lander designs call for four engines in that compartment,  each firing through its own port in the heat shield.  The storable propellant engines on the transit vehicle should also likely number 3 or 4.  There should be at least 2 engines on the hydrogen-oxygen departure stage.  Thus every propulsion installation has multi-engine reliability.  Further,  there is larger lander thrust turndown capability with multiple engines. 

Rough-Estimate Costs

This is very rough,  “shoot-from-the-hip” stuff.  Take it with more than a grain of salt.  But the point is,  these estimates are very much smaller than those for the “90 day report” and “design reference mission” scenarios presented to congress. 

The reason is twofold:  (1) this is a very different mission plan than any of those other proposals,  and (2) with the exception of the lander design,  the hardware proposed here is not very developmental at all.  It is basically only re-shape,  re-size,  and test-to-prove it works,  of stuff we already build.  Only the landers do not fit that description.  They must be developed “from scratch” and tested extensively to trust that they will function.  That’s a lot more expensive. 

For hardware costs,  most items I simply estimated as $4 million per dry ton.  Launch costs assumed current launchers,  flying fully-loaded,  for a unit price to Earth orbit of $6 million per ton delivered.  The new Falcon-Heavy reduces that considerably,  and it should fly for the first time in 2016.  But I did not take advantage of that beneficial effect in my calculations.

For the landers,  I assumed a factor-100 higher cost of $400 million per dry ton,  to represent the extensive engineering development project that this will be.  Accordingly, development costs, not launch costs, dominate the figure I got for adding the landers to the mission.  The manned transit vehicle is dominated by launch costs,  precisely because it has little engineering development needed. 

For propellant costs,  I “shot from the hip” and used $800/ton (about $2.3 per gallon at 6.5 lb/gal) for the ordinary rocket propellants,  and 10 times that at $8000/ton for the electric propulsion propellants.  These may not be right,  but they have to be “in-the-ballpark” enough to be at least somewhat realistic. 

My results are given in Figure 8 below.  Building the manned orbit-to-orbit transport and sending it to Mars and back totaled something in the neighborhood of $15 billion,  dominated by launch costs for which propellant was trivial.  Adding the 3-lander fleet with propellant for 3 flights per lander was surprisingly modest at $26 billion,  dominated almost entirely by the lander development costs.  The total was still under $50 billion to send 6 people to the surface of Mars at up to 8 different sites,  and bring them and their transit vehicle home,  with spin gravity for assured crew health.  The transit vehicle gets used again for other missions. 

In comparison,  the 90 day report and design reference mission scenarios were quoted to congress a few years ago as $450 billion (probably over half a trillion today) to put 2 to 4 people on Mars at one single site.  The entire manned vehicle was thrown away doing this. 

There is no comparison here!  My old 1950’s way,  updated for today’s technologies and hardware,  is just far, far better. 

 Figure 8 – Resulting Very Rough-Estimate Costs

Challenge for Readers

Use my basic orbit-based mission design,  and see if you can add some nuances and thus squeeze even more bang for the buck out of this.  Some of you have better tools than the ones I used:  a simple hand calculator and ordinary spreadsheet software on a laptop. 

Challenge for Spacex

Get with Bigelow Aerospace and start working on the transit vehicle now.  This stuff can certainly be launched with your Falcon-Heavy,  and uses your Dragon v2.  Think men-on-Mars by 2025,  paced by the lander.  You can show the world how this is really properly done. 

Challenge for ???

“Somebody” needs to get started on the reusable lander,  as it is the pacing item preventing launching men to Mars by 2020.  The booster-landing experiences of both Spacex and Blue Origin are very applicable here.  The Dragon v2 propulsive landings will also be highly and directly relevant.  


See also "Reusable Chemical Mars Landing Boats Are Feasible",  dated 8-31-2013,  located elsewhere on this same website:  paper rough-out designs for a one-stage lander,  done for 4 propellant combinations.

See also "Space Travel Radiation Risks",  dated 5-2-2012,  located elsewhere on this same website:  accumulated dosages for a "typical" manned Mars mission,  with either just a shelter space,  or a shelter space plus shielding around sleeping quarters.  

Update 6-14-16:  This one is based on the orbit-to-orbit transport carrying people both ways,  with separate landers staged out of orbit.  This make a lot of sense from a site selection flexibility standpoint,  and it does not depend at all upon our being able to manufacture suitable propellants on Mars.

Such propellant manufacture feasibility has been established;  the question how much / how fast can we make it?  The prime propellant for this activity is LOX-liquid methane.  That is not compatible with the long-term storable NTO-MMH that I selected for this study.  To use it,  the landers would need to be the LOX-methane design.

The cryogenics are also subject to boil-off losses over time.  The Dewar construction and insulation to counter boiloff will add significantly to inert weights.  It would be hard to ship them from Earth because of the 8-9 months of boil-off losses.  But if manufacture on Mars fails for some reason,  any reason at all, then you lose your ability to land,  after going to all the trouble to get there!  I see that as an unacceptably-undesirable outcome,  even if low probability.  You would have to ship enough LOX-methane from Earth to get a baseline mission done,   if only low or no mass quantities are available on the surface.

The counter-argument to that is sending the propellant manufacturing capability ahead as a robot facility.  Don't send men until you know you have enough on-hand to do what you want.  There is an advantage to having lander propellant made at Mars.  You can swap out un-needed descent propellant for extra cargo tonnage,  and fuel-up on the surface for the ascent.  That makes it far easier to land lots of equipment with any lander design,  even this reusable one. Plus,  you can fly suborbitally to explore other sites.

But you must have at least some propellant on orbit,  for the rescue lander.  That will simply have to come from Earth.  If you don't do that,  you do not have a rescue capability for a stranded lander crew.  Period.  Further,  it doesn't make a lot of sense to be shipping up tonnages of propellant from the surface,  because ascent payload fractions will be inherently far smaller.  So proposing to use Mars propellant as crew return propellant is less attractive than you might think at first glance.

All in all,  I still kind of like best the updated version of the 1950's mission design.