Friday, December 13, 2013

Mars Mission Study 2013

This is the culmination of about 3 years' effort on my part toward roughing-out practical manned Mars mission designs.  I started with nuclear rocket solutions that drew many objections.  This study is what it looks like when you combine all-chemical propulsion for the transit vehicles and the landers,  with historically-valid concepts regarding the purpose of exploration,  and with the ethical consideration of designing-in "a way out" for crew self-rescue at every step possible.  And,  this is what it looks like when you pay attention to what we already know is crucial for successful long-distance travel in space (another ethical consideration).  Updates 12-20-13 in red.  Update Dec 31 2013 at end in blue.


In November and early December,  I roughed-out a series of chemically-powered manned Mars mission scenarios somewhat similar to my nuclear-powered Mars Society 2011 paper (ref. 1),  and my associated subsequent second thoughts (ref. 2).   This was based around the same ideas of multiple landings in the one trip,  and a reusable one-stage chemically-powered Mars lander (similar to the design in ref. 3).  To that mix,  I added the notions of starting some sort of base at one of the sites visited,  a visit to Phobos,  and storing all the reusable and salvage assets in stable locations (not even one propellant tank is discarded,  every single thing is salvaged for re-use!).  All of this is actually a feasible thing to do.  Done right,  the price tag is order-of-magnitude closer to $100 billion not $1 trillion.

I went through a couple of scenarios based on capture into a high-apogee elliptical orbit,  which reduces arrival velocity requirements a bit,  and makes a visit to Phobos relatively easy.  However,  a one-stage reusable chemical lander of significant payload fraction is far too limited in velocity capability for anything but a low circular orbit to be practical.  This orbit needs to be inclined at the value of the farthest latitude of interest,  so as to eliminate the plane changes the lander cannot afford. 

These scenarios,  and those in the references,  all begin by addressing what is really to be accomplished by sending people to Mars.  That is a far harder task than going to the moon was,  by far.  Figure 1 explains why that is true.  But,  this is now within our technological grasp,  so we should go.  Figure 2 relates the drive to do this to the entire history of humanity.  It is the manifestation of an urge that is simply built into us.  Exploring and colonizing new places is what we have always done.

Figure 1 – Why Sending People to Mars and Back is So Hard

Figure 2 – The Drive to Go to Mars Is Part of a Very Old Urge

Going to and settling new places is colonization,  pure and simple.  It is no different with space travel.  There are new places out there to explore,  and maybe settle.  Thinking long-term,  colonization is what it is all about,  even though the initial trips of course have a far more limited scope (they always have).

The most successful approach used half a millennium ago settling the New World is the 3-step process shown in Figure 3.  Those are given names here as (1) exploration,  (2) adaptation,  and (3) colonization.  While shown as separate blocks in the figure,  these steps inherently overlap a little (they always have). 

Exploration,  properly done,  answers two very deceptively-simple questions,  shown in the figure.  I mean them exactly as they are phrased,  word-for-word!  Until you have answered those,  you cannot learn how to live in the new place,  much less establish settlements,  or a full-blown colony,  because you still don’t know what is there that you can use.  How simple is that?  Yet,  so very challenging!

The concept of “ground truth” gets into this with the technologies we have today.  Remote sensing can tell you that there seems to be water in this place on Mars,  and not that one.  But,  you do not know for sure the sensing result is correct,  you do not have any information regarding how much is really there,  or that its quality is something you can use.  Even today,  we must visit the site with a drill rig and look deep underground in multiple places to quantify whatever resources are there.  So far,  we have no robots who can do that job on Mars.  That’s why people must go:  to complete the exploration process

The second step is adaptation,  which is basically learning how to use local resources to live there.  That’s your first base or settlement,  maybe more than one,  maybe not.  There’s two broad categories here:  dependent and independent living.  You start out dependent on supplies shipped from home,  augmented as best you can by what you can produce locally.  On Mars,  food,  water,  and air are all very big problems.  So is propellant production.  So is all sorts of infrastructure. 

Later,  as you learn to do more with the local resources,  you gradually shift into independence from critical supplies shipped from home.  That does not happen very fast.  It’s not something that can be planned thoroughly ahead of time,  precisely because you are adapting to an environment new to you. 

But,  once you are independent of basic survival supplies shipped from home,  that’s when you can begin shifting from being a base doing adaptation,  into being a real settlement or colony making your own living in the new place.  It happens very,  very gradually.  It always has.  You don’t just “land one!”

Figure 4 shows the best historical approach for who pays for what phases in this 3-step process.   The most successful colonies came from doing exactly those 3 steps,  funded in this way.  However,  great thought must be given to what sort of trade economy will be built as the colony matures.  It has to go beyond simple extraction of local resources that folks back home might find valuable.  Historically,  those colonies who never got beyond the resource extraction goal are now mostly still Third World countries.  Those for which a real two-way trade economy got established early are now prosperous nations.  This was done more by chance back then,  we should not make that mistake today

Figure 3 – The Historical 3-Step Process That Was Most Successful Colonizing the New World

Figure 4 – The Historically Most-Successful Way That Colonization Is Funded

All that being said,  the realities of the politics-of-money today suggests that there will be one and only one manned expedition sent to Mars at government expense.  It does not matter to that conclusion whether one government does this alone,  or several governments band together to do this.  It does not matter if a few visionary private entities participate,  it is government that funds the lion’s share of that first trip,  just as it was long ago.  Initial exploration is what governments have always funded,  it is unreasonable to expect that going to Mars will be any different.  It is also unreasonable in today’s world to think they fund two or more successive trips. 

What that means is that the first expedition must accomplish fully the first step (exploration),  and put the assets in place for a first base (start the second step) at the best possible site.  That is what is shown in Figure 5.  Once that first base is in place,  even if it is not initially manned permanently after the expedition leaves,  it acts to draw the visionary private entities who “smell” an opportunity.  This is not fundamentally different today than 500 years ago.  “If you build it,  they will come” is actually true.

We already have technologies we can take to Mars that could potentially make water,  air,  and perhaps even rocket propellants on Mars,  given the right site resources and conditions.  (Food production is a much tougher problem,  that’s part of what the adaptation base is eventually for.)  We might even be fairly sure of our technologies when we go that first time.  The problem isn’t the technologies so much as it is getting the “right” site.  There,  just like here,  every site will be different and none will be exactly “average”.  To expect otherwise is either na├»ve,  or unreasonable,  or both. 

Thus it is imperative that we visit more than one site in that first exploratory trip.  We have to pick the “best” one of those,  meaning the one where the local resources best match up with the technologies we brought with us.  We’ll have more than one potential landing site identified before we go.  The real objective for the people on the expedition is to find out,  with actual ground truth,  which candidate is actually the best site for the base.  You do that by trying out your adaptation technologies at all of the sites.  That is why Figure 5 says what it says. 

If you don’t visit more than one site,  your chances are much lower of building an adaptation-development base that is successful enough to draw the private entities into a majority funding position for subsequent expeditions.  If you don’t build such a base on your first trip,  then your first expedition essentially devolves into a “flags-and-footprints” mission.  Given the difficulty and expense of going all the way to Mars with people at this time,  that would be entirely pointless!

That imperative to pick a “best” site and start a base is why I do not think there is much value to the many minimalist mission plans I have seen proposed that just make one landing,  direct or otherwise,  even though their price tags are closer to $10 billion than $100 billion.  Our remote sensing is just not good enough to bet lives and potential settlement-attractiveness on it.  So,  this old saying is actually quite true about sending people to Mars:  “Go whole hawg or none”.

Figure 5 – Goals for the First Mission

Roughing-Out A Mission:  Start With the Lander

Given the imperative to make multiple landings,  it is the landing craft and its propellant supplies that will “drive” the mission design.  This is because that will be one of the larger masses that must be “dead-headed” to Mars,  the other being the propellant supply for returning the crew to Earth.  Betting their lives on return propellants manufactured on Mars is unwise and unsafe,  because you don’t really know your equipment will work well enough at the site you pick,  until you actually try it!  The answer could just as easily be “no it won’t work adequately” as “yes it will”.  The point is,  you don’t know for sure. 

That is why in Ref 1 and 2,  and this study,  I send enough propellants from Earth to accomplish the entire mission safely.  Anything made locally just augments that supply,  making more sites potentially explorable,  and making the base left behind more attractive to those who follow.   You do that in the second half of the stay,  when you are surface-based,  by using your landers in suborbital flights,  with the propellants you have made while you are there.  

In refs. 1 and 2,  I was looking at single-stage nuclear-powered reusable landers.  But,  unlike the transit vehicles,  in a lander there is little radiation shielding available from the structure and the distances.  So,  in ref. 3 I looked at a family of chemically-powered landers,  to be used from a low Mars orbit at 200 km.  All had the same 3 ton payload.  The liquid oxygen (LOX) – liquid hydrogen (LH2) produced the smallest lander mass by far.  The others,  including otherwise-attractive LOX-liquid methane (LCH4),  were all 60 tons or higher in ignition mass.  Yet all were feasible as single-stage reusable vehicles,  to be refueled on-orbit from orbiting supplies,  and flown again.  That payload fraction is a bit low at 5%.

Looked at another way,  the high specific impulse (Isp) afforded by LOX-LH2 simply produces higher payload fraction at otherwise equal conditions,  by far.  These November-December 2013 studies were aimed at a larger fixed payload mass of 11 to 12 tons.  This time,  the only feasible configuration was a 79 ton LOX-LH2 lander with a rather attractive 14% payload fraction.  Even LOX-LCH4 never exceeded about 5% payload fraction,  or got under about 200 tons ignition mass.  Numbers like that very quickly push you into building unaffordable “Battlestar Galacticas” just to get there and back.  It's bad enough just reusing every single asset,  including propellant tanks.  

LOX-LH2 also makes the best sense for transit propulsion,  again due to its substantially-higher Isp.  If you use the same propellant for both transit and lander,  you only have to worry about one kind of propellant tankage to contain it,  and you could use similar,  if not exactly the same,  rocket engines for all vehicles.  Those are things that simplify design and reduce weight. 

That kind of thinking leads immediately to a modular vehicle design with a common propellant module that is easily launched,  plus the use of multiple assembled vehicles,  so that assembly and transits-to-Mars can be spread-out over time before the people go.  If you use the landers themselves as their own transit propulsion,  that saves even more inert weight.    This was the basis of the nuclear LH2 vehicle fleets in ref. 2,  and it is the basis of the LOX-LH2 vehicle fleet in this study. 

Accordingly,  the lander design requirements used in this study are given in Figure 6.  Note the slightly-higher orbit altitude of 300 km,  guaranteeing good stability for the year this fleet will spend at Mars.  That orbit will be raised at departure to 500 km for even longer-term storage stability of the reusable and salvage assets left at Mars.  My terminal descent requirement is (I hope) a conservative guess. 

The basic lander design criteria and assumptions are given in Figure 7.  20% total inert fraction is barely credible for a vehicle that flies several-to-many times.  Experience with a variety of vehicles says that robustness is heavy.  The 11 ton dead-head payload includes a crew of 3 plus a month’s supplies,  and about 9 tons of exploration and experimentation equipment.  This would include a rover with a big drill rig on it,  capable of reaching around a kilometer down.  The surface habitation is in the lander itself. 

Figure 8 shows the lander weight fractions I got with LOX-LH2 and LOX-LCH4.  There is no question that LOX-LH2 is the better choice.  A 200+ ton lander with LOX-LCH4 just drives you into building “Battlestar Galacticas”.  79 tons with LOX-LH2 is bad enough:  it will require assembly from smaller components in low Earth orbit (LEO),  but that can actually be done,  as partially proven by the construction of the ISS. 

Lander layout and weight statement is shown in Figure 9.  Note that the stance is about as wide as the lander is tall,  so it will have good stability,  even on rough terrain.  The dimensions are consistent with the masses and densities of the propellants,  and the masses and dimensions of the other cargo items and crew living space requirements.  The decks above the main cargo floor remain pressurized for the crew to live in,  on the surface.  The cargo deck is around the engine compartment,  and between the 3 (or 4?) retractable-landing leg bays.  The crew cabin is actually a minimal abort capsule to get the crew to the surface without killing them;  it has 6 seats,  even though I planned on a usual crew of 3. 

This lander has an engine compartment that is sealed gas-tight to the rest of the vehicle.  Its only openings are the ports the four engines fire through;  and those have no covers,  they remain wide open during hypersonic entry into Mars’s atmosphere.  Because the compartment is sealed,  there is no through-flow of oncoming superheated gas,  quite unlike the shuttle Columbia’s damaged-wing situation that killed it and its crew.  Nothing insulates as well as a gas column. 

On entry,  this vehicle comes out of hypersonics (local Mach 3) about 10 to 15 km altitude,  which is way too low for a chute to deploy,  much less do any deceleration “good” on an object this big and heavy.  So,  instead,  the engines simply fire up in supersonic retro-propulsion,  for a direct rocket-braking landing.  This process is actually what sizes the four lander engines,  which are slightly canted at about 10 degrees,  to provide plume stability during supersonic retro-propulsion.  Engine specifications and design data are given in Figure 10.  I did not include the detailed results of my entry analysis here,  although the crew feels not more than about 1.5 gees the whole way. 

Figure 6 – Velocity Requirements for the Lander with Low Orbit Basing

Figure 7 – Basic Design Criteria and Data for the Lander

Figure 8 – Verifying Propellant Choice

Figure 9 – Lander Layout and Weight Statement

Figure 10 – Lander Engine Specifications and Design Data

This same lander pushes its own landing propellant supply to Mars one-way.  The basic idea is to divide the approximately-one year stay at Mars into two phases:  explore a few sites based from orbit the first few months,  and then establish a base at the best one of those sites,  where everybody stays the remainder of the time at Mars.  During that second phase,  the crew leaves the return vehicle and return propellant supply in orbit,  until departure.  This process is depicted in Figure 11. 

This two-phase process also designs-in maximum crew safety.  During the first (orbit-based) phase,  3 go to the surface in a lander,  while the other 3 do science from orbit,  with a “reserve” lander available for rescue.  If you send 3 not 2 landers,  then you always have a rescue “bird” available,  even if one should fail.  That way,  you need not abort the mission if one lander fails

During the second phase,  you bring all 3 landers and all 6 crew to the base at the best site.  If you are able to make propellant locally,  it can be used to support suborbital missions to yet other sites,  using those same landers.  But,  you still have a rescue “bird” and a backup,  if something goes wrong.  One of those 3 landers is all it takes to get the entire crew back to orbit,  although the initial concept calls for leaving as many landers as possible in orbit,  when the crew departs to come home.   

The philosophy here is designing-in a “way out” at every phase of the mission.  Nothing else is ethical. 

Figure 11 – The Two-Phase Process to Both Explore and Establish an Initial Base on Mars

Roughing-Out A Mission:  Decide Upon Some Modules

I ran enough numbers for space per person and supplies per day in ref. 4 to rough-out a generic habitat module (see fig. 12) and a generic stored supplies module (see fig. 13).  Two of each are enough for a crew of 6 for nearly 3 years.  So,  I just used those design numbers here.  The habitat modules at just under 25 tons each (as loaded) could be launched one-at-a-time by the heavy-lift variant of Atlas-V,  or two-at-once by a Falcon-Heavy.  The storage modules are just under 50 tons each,  requiring a Falcon-Heavy to launch them one-at-a-time.  Both are 5 m in diameter.   

My prior studies were hydrogen-propelled nuclear thermal designs.  Those modules are not quite what is needed here with LOX-LH2 chemical propulsion,  but all the same ideas and features apply.  I roughed out spherical insulated cryo-tanks for LOX and for LH2 that would fit end-to-end within a shell 5 m in outside diameter.  This shell would cover some truss structure,  and have an outer layer that is really multiple layers of foam-and-foil meteoroid shielding.  See fig. 14.

There is plenty of volume in the ends of this propellant module for fold-out docking gear,  accommodating both end-to-end and side-by-side docking,  in a variety of stack configurations.  Solar cells along the outer surface would power a small cryo-cooler in each module.  I simply guessed that 5% inerts would cover all of this,  since these tanks get launched once,  and stay in space thereafter,  even if and when they ever get reused. 

Figure 12 – Habitat Module (2 Required for Crew of 6)

Figure 13 – Supplies Storage Module (2 Required for Crew of 6)

Figure 14 – Common Propellant Module for LOX-LH2 Vehicles

My original idea was to push everything to Mars with the landers.  This did not make as much sense for the manned vehicle,  because that would bring one lander back to Earth instead of leaving it at Mars where it could be used again.  As the vehicles sized out,  the landers pushing dead-head propellant were larger and heavier than the two-way manned vehicle.  The better solution was an engine module specifically for the manned vehicle,  with two engines for redundancy.  The fleet concept is shown in Figure 15. 

The thrust level of one lander engine was sufficient,  so the engines on the manned vehicle engine module would be very similar to the lander engine,  just half thrust.  I took an educated guess for engine weights and structure for the module using 50:1.  Those numbers are given in Figure 16.

The velocity requirements for the trip to and from Mars were figured for worst-case planetary alignment (Mars at aphelion and Earth at perihelion).  See Figure 17.  An orbit-raising requirement was also computed,  as the landers and empty tanks left there need an orbit stable over several years,  not just one.  I included this orbit-raising maneuver in the propellants computed for the unmanned vehicles,  and in the manned vehicle return configuration.  The plane change at arrival was assumed to be direct entry to 40 degrees inclined from the interplanetary transfer ellipse,  and the same for return.

Note that both the departure and arrival (and any orbit change) requirements are included in the total velocity requirement.  No empty propellant tanks are staged off after each burn,  every single asset is left where it can be recovered and re-used.  

Figure 15 – Concepts for Vehicle Fleet to be Assembled in Low Earth Orbit

Figure 16 – Engine Module for the Manned  Vehicle

Figure 17 – Velocity Requirements for a Low Orbit-Based Mission at Worst-Case Planetary Alignment

In Figure 18 are the requirements for a Phobos excursion from the low inclined orbit.  This includes a plane change maneuver at apoapsis to reach Phobos,  and the same to return.  As it turns out,  the velocity requirement for this trip is only slightly less than the design velocity requirement for any one landing on Mars.  Thus it takes the same 3-propellant-module quantity of propellant to fuel up for a round trip to Phobos,  as it does to land on the surface of Mars.  The dead-head supply for the landers is thus 6 landings on Mars and one trip to Phobos:  7 trips,  for 21 propellant modules. 

The rest of the dead-head propellant supply is that required for manned vehicle return (to Earth orbit for reuse!!).  For safety purposes,  it is assumed that rendezvous and docking in Mars orbit will be reliable,  as it is here.  Apollo made that same assumption at the moon.  On the return trip, it is assumed that the supplies are 2/3 depleted at start of the return voyage,  and wastes have been left behind.  This lightens up the two storage modules by quite a bit.  That configuration needs about 17 propellant modules to make the return voyage,  as shown in Figure 19.  The heavier configuration for the outbound voyage at full supply weights requires more modules (some 28).  This is also shown in Figure 19.  Both configuration spin end-over-end for 1 full gee artificial gravity as shown.

This total dead head propellant supply is split up among the 3 landers,  and propellant modules added until they can meet the velocity requirements to reach orbit about Mars.  Each lander thus has 54 modules to push and draw from,  as shown in Figure 20. 

Figure 18 – The Phobos Excursion

Figure 19 – Manned Vehicle Configured for the Return,  and For Outbound to Mars

Figure 20 – Dead-Head Propellants and Landers as One-Way Unmanned Vehicles

The launch manifest for assembling this fleet in low Earth orbit is given in Figure 21.  This listing includes everything that departs for Mars,  plus 9 more propellant modules that fuel up the landers for departure.  These 9 modules remain in Earth orbit.  With one important exception,  everything to be launched fits atop existing commercial launchers (Atlas-V,  Delta-IV,  and Falcon-9),  or one that will fly in 2014 (Falcon-Heavy).  These vehicles are assembled by simple docking in orbit,  the same as was the International Space Station.  There is no new technology to be developed here. 

The exception to all-assembly-by-docking is the lander design:  this has a base diameter of 12 meters and so is far too wide to fit any of these launchers,  even though the dry weight for the entire lander is feasible for Falcon-Heavy at just under 27 tons.  The landers will require “real” assembly from smaller components on-orbit,  something not so very practical with today’s typical spacesuits.  Conceptually,  I divide a lander into a less-than-5-m diameter core,  a load of decking and framing plus landing legs,  and a load of shell plating and heat shield panels plus the cargo-handling gear.  These would be nominal 9 ton loads,  launchable by 3 Falcon-9’s to build one lander.    But,  it has to be put together in zero-gee and vacuum,  and that’s what we have never done before.  It’s more new skills than it is new technology. 

The total tonnage in the manifest is 3725 metric tons,  most of which is propellant modules that simply dock together,  and their plumbing gets coupled up.  Atlas-V and Delta-IV are costing in the vicinity of $5000/kilogram when flying at or near full load.  Falcon-9 is significantly less expensive,  and Falcon-heavy is projected as a lot less expensive.  That produces the launch costs given in Figure 22.  A wild guess puts launch costs at 20% of program costs,  for something a lot closer to $100 billion than $1 trillion.  It is about half the numbers that I got for the high-orbit basing scenarios. 

Figure 21 – Launch Manifest for the Fleet

Figure 22 --  Conclusions and Costs – Base in Low Orbit!

Concluding Remarks

What I have presented is a manned Mars mission plan that (1) makes sense in terms of what exploration really is and does,  (2) makes sense in terms of the politics-of-money,  (3) requires no major new technology developments,  (4) reuses every single asset,  including all empty propellant tanks,  and (5) builds in safety and a self-rescue “way out” for the crew to the maximum extent possible every step of the way.  That last is important because the hard lessons of the Apollo 1 fire and the two lost shuttles is that “nothing is as expensive as a dead crew”.

Items (1) and (2) are very important.  Sending people to Mars and back is far too difficult and expensive to waste it on a “flag-and-footprints” stunt.  It is very likely that only one mission will ever be sent on largely government funding,  and even that is not a sure thing.  That one mission had better lay the groundwork work for the largely commercially-funded permanent base efforts later,  efforts that might eventually result in a permanent settlement and colony. 

Item (3) is a real “killer” for government-funded efforts.  Programs emphasizing major new technology developments simply do not provide flying vehicles.  Examples:  X-30,  X-33.  If you really want to go to Mars now,  you do it with what you have now!  Period!  This does not rule minor items like a new spacesuit,  but it does rule out major items like waiting for new propulsion.  Using what you have is how we went from nothing to the moon in about 10 years.  That’s what is required to reach Mars in only about 10 years. 

Item (4) is crucially important in a longer time frame sense,  because return missions to Mars (no matter who funds them) can use the assets already there,  and because vehicle assets recovered into Earth orbit can be re-purposed and re-used for other missions.  Why launch new hardware if you don't have to?  Just launch new propellants and supplies,  and make the trip,  whatever it is.  

The modular vehicles outlined here could easily by reconfigured to accomplish the other space missions beyond Earth-moon space that we might be interested in.  These would include missions to near-Earth asteroids for purposes of learning how to defend against asteroid impact.  It might include trips to the main asteroid belt beyond Mars.  It could include trips to Venus orbit,  and even to the surface of Mercury.  

If you put the water and wastewater tankage around the flight control station in one of the habitat modules,  and make it big enough for the whole crew for about a day,  you have solved the radiation protection problem.  By spinning end-over-end at the very modest rates indicated above,  you have solved the microgravity disease problem  with spin artificial gravity.  That also simplifies a variety of long-term life support issues as well. 

The needs that I forsee are twofold:  (1) we need a supple,  lightweight,  nonrestrictive spacesuit,  and (2) we need the skills and experience at real construction in Earth orbit to support building the landers “from scratch”.  Possession of those two items feeds back into the Mars mission and anything else we really want to do in space,  in so many ways that it is not feasible to list them here.  And,  these two items go together:  it is not possible to do nuts and bolts construction work,  or plumbing,  or wiring,  with the clumsy suits that we now have.  That is the real need that must be addressed to go to Mars. 

Note that I did not specify the atmospheres to be used inside the vehicle modules or in the landers.  That would inherently go with the spacesuit design,  so that decompression for nitrogen-blowoff is unneeded for going outside.  Yet there are extreme fire dangers and health risks associated with pure-oxygen breathing. 

We have already done these selections for the shuttle and all the space station programs going back decades.  We simply need to do it again with the new suit that we have to have.  I suggest this should be a mechanical counter-pressure (MCP) suit,  but done in a new way as “vacuum-protective underwear”.  But,  that’s another topic.   Some fundamental compression requirements for it are given in ref. 5. 

Update 12-31-2013 

This study is,  in many ways,  an upper bound on a practical and reasonably safe mission design that produces a great deal of results almost no matter what actually happens.  So,  to reduce tonnage launched and thereby mission cost,  what can you give up on?

To stay very productive no matter what,  you cannot give up on basing from orbit and visiting multiple sites early in the stay at Mars,  and your landers must refuel and fly multiple times.  Nor can you give up on establishing that adaptation base on that first mission,  given politics-of-money in our time.  

To stay safe,  you cannot give up on sending the exploration and return propellant supplies from Earth,  and you cannot give up on sending 3,  not 2 or 1,  landers.  

To stay healthy,  you cannot give up on supplying radiation protection and pretty near 1 full gee of artificial gravity.  A modular baton-shaped ship design that spins end-over-end is definitely the most effective way to do artificial gravity.  

What you can give up on is saving every single scrap of hardware for reuse or salvage.  I roughed-out my designs for the manned and unmanned vehicles by making both departure and arrival burns from a set of propellant tanks initially full,  without staging off any empties before making the arrival burn.  One could stage off those empties into deep space (actually the transfer orbit,  so there are long term collision risks) after the departure burn.  I have not yet investigated this,  but I'd guess the savings would be closer to 10% than factor-of-two.  

What you do not want to give up on,  unless forced to "at gunpoint",  is recovering the manned vehicle in Earth orbit at mission's end.  Jettisoning this vehicle into deep space (actually the transfer orbit,  so there are future collision risks) allows you to eliminate the arrival burn in favor of a free return.   This will save some propellant tonnage,  but it loses you future use of something very expensive to launch:  the assembled crew habitation and supply storage,  and its transit engines,  at the very least.  

This would be "penny-wise but pound-foolish" mismanagement,  because those very same items can return to Mars,  visit near-Earth asteroids,  or even go to Venus or Mercury.  With some hotter propulsion substituted,  those same components could even take men to the main asteroid belt.  

Why build them too fragile and throw them away,  again and again and again?  That's stupidity incarnate.  

Build them tough and launch them once,  and fly them to many places over many years.  


1. G. W. Johnson,  “Going to Mars (or Anywhere Else Nearby)”,  paper presented at the 14th International Mars Society Convention,  Dallas,  Texas,  August,  2011.  A version is posted at,  dated 7-25-11,  same title.  (Nuclear-powered designs.)

2.   .2.  G. W. Johnson,  “Mars Mission Second Thoughts Illustrated”,  posted at,  dated 9-6-11.  (Nuclear-powered designs.)

3.    3.   G. W. Johnson,  “Reusable Chemical Mars Landing Boats Are Feasible”,  posted at,  dated 8-31-13.  (Chemical 1-stage reusable landers.)

4.    4.  G. W. Johnson,  “Rough-Out Mars Mission with Artificial Gravity”,  posted at,  dated 7-19-12.  (Nuclear transit,  undefined landers.)

5.       G. W. Johnson,  “Fundamental Design Criteria for Alternative Space Suit Approaches”,  posted at,  dated 1-21-11.  (Applicable to MCP suits)

Friday, November 22, 2013

Windows 8 Sucks

(see also updates below,  in chronological order)

A warning for you all:  do not (I repeat DO NOT) buy any sort of PC equipment with a Windows 8 operating system!

Update 6-22-16:  Windows 10 is just as bad if not actually worse.  See below.

Windows 8 is absolutely the worst version of Windows I have ever seen,  and I have seen them all since the very first one.   The 8.1 update does not (I repeat DOES NOT) fix this.

Their fundamental mistake is so egregious that I have difficulty expressing myself precisely without profanity. They wanted non-touch screen devices to look like touch screen devices,  even though that concept is completely pointless.

The operating system bogs down a stop,  with all the useless touch screen stuff running in the background. Internet things quit loading completely,  even though an older machine does fine,  in a side by side test on the same local area network.

Please,  all of you,  boycott Microsoft until they withdraw this worthless product,  and tell them why you are doing it.  It is THAT bad!


PS -- update 12-19-2013:

The Windows 8 operating system sacrifices usability for style.  It looks like the Apple-based smart phone and game devices they are trying to compete with.  But,  it sacrifices utility and access to do that.

Microsoft completely forgot about its real customer base coming up with this abortion:  the working stiffs like me who really have to accomplish nontrivial tasks in word processing,  data handling and calculation,  and results presentation.

The Apple-type devices are simply inadequate to nontrivial tasks like that.  For one thing,  their keyboards (if they even have one) are very clumsy transitioning from alphabetic characters to numeric characters,  and back.  That's just one reason why we working stiffs buy PC-type equipment instead of Apple-type equipment.

Now Microsoft has screwed-up their advantage with Windows 8.  It takes more keystrokes to access what you need to do your job,  and the stuff you want to use is hidden in more arcane places (way harder to find).  Doing that to an otherwise loyal customer base,  just to add a few more customers from a different market,  is the very height of management idiocy.   The two product lines should have been kept separate,  the new dual-mode tablet/laptops notwithstanding.

Recent Microsoft executives are thus demonstrably (by their new product decisions) far less competent than we customers have every right to expect from a company that big and established,  especially one in such a near-monopoly position.

Shame on you,  Microsoft.  The Bill Gates that I knew of (from the old stable DOS days) would not (and should not) be proud of you.  I wish he would come back and set things to rights again.

Update 1-3-2014:

I have figured out how to turn off most of the Apple-like “app” crap that I don’t use.  I had to figure it out for myself,  there was no effective help from the store where I bought it,  in spite of the service agreement that I bought.  Turning off many resident programs did greatly improve my internet connectivity,  but didn’t wholly “fix” the problems. 

Turning off unneeded programs reduced the resources being used in the computer,  but more importantly,  reduced the in-the-background internet update activity.  This freed up internet data transfer capacity enough where I could actually function on the internet.  Out here in the country,  my internet comes over a cell phone tower.  It’s way better than dial-up,  but way slower than the high-speed stuff available in the cities.  That somewhat-slower internet service is why the unneeded programs using internet were so intolerably vexing to me,  specifically.

By the way,  the store where I bought this laptop lied to me about that issue.  They told me none of these resident programs used internet.  But I could see the images and data in the icons on the screen updating (which requires internet),  and turning these things off did actually make a substantial difference.  I really don’t like being lied-to by store tech geeks.  So I probably won’t ever buy anything from that particular store again.

Turning unnecessary crap off helped a lot,  but did not “fix” everything.  I still have erratic connectivity problems far too often.  These take the form of incomplete page loads that require 1,  2,  even 3 refreshes before getting a complete load.  Sometimes I get the little spinning-circle “busy” signal,  sometimes not.  Photos failing to load on web pages or in emails is the most reliable indicator,  and it still happens about half the time.  That’s way,  way too often.

Internet connectivity still fails completely,  however,  about every 2 to 3 days.  It shows up as getting the “busy” circle “forever” instead of getting even a partial page load.  By “forever” I mean as many minutes (minutes not seconds !!! ) as I have the patience to endure.   I do not have the patience to see if it goes on like that for an hour or more.   And,  when this begins to happen on the internet,  I also start to see spinning-circle “busy” signal delays just opening programs while NOT on the internet.  That has to be the Windows operating system corrupting itself,  and maybe the effects of more in-the-background Apple-like “apps” that I haven’t yet found and turned off. 

When this problem happens,  the only “cure” I have found is a complete cold shutdown and restart.  If locked-up this way while on the internet,  quite often there is no way out except to push the power button to kill the computer.  Nothing else works!  And unlike all previous machines and versions of Windows that I have had,  sometimes the little lights indicating internal activity won’t go out,  even when you kill it with the power buttonMeaning,  it didn’t really shut down,  it just wants you to think it did.  And THAT just doesn't fix the corrupted-Windows operating system problem.

I get a more reliable power-button “kill” if it is unplugged from the charger – why that should be,  I absolutely cannot understand,  unless it is using something none of us know about,  coming in over the electric power grid (I know,  that sounds like a conspiracy theory).  But,  getting a more reliable “kill” when off the charger is empirically true (I dare anyone to explain THAT).  If the lights persist “on” after I go for cold shutdown,  the only option available is to “kill” it again with the power button,  however many times it takes,  until all the lights stay off.  And that is quite exceedingly ridiculous!

These problems that I fix by cold shutdowns have to be something traceable to the Windows operating system,  precisely because it is a fresh copy of Windows that is drawn from memory upon restart.  Everything else depends on the operating system.  I’ve seen this before,  with other versions of Windows,  but the time scale between restarts was several days with versions like 98,  even weeks with very early versions like 3.1,  not two lousy days with 8/8.1!  Windows 8/8.1 is quite apparently an unstable disaster,  because of how very quickly it corrupts itself.   And THAT is atrociously ridiculous!

The tech geeks at the store where I bought this laptop also lied to me about installing Windows 7 versus Windows 8.  They said Windows 7 could NOT be installed on this model,  and repeated that assertion when I questioned it.  So I called the actual maker of the laptop:  there are 3 (and only 3) different drivers required to use Windows 7 instead,  all available for free download from the maker’s website.  As best I can tell,  this model laptop came with Windows 7,  before Microsoft released Windows 8 and then bullied everybody into only offering computers with Windows 8 on them.

Windows 8 is a very flawed product,  and absolutely the wrong product to be on any non-touch screen device.  Shame on you Microsoft for abusing your non-touch screen customer base this way!  If there were a viable alternative,  I would never buy another Windows product,  but Microsoft is a de-facto monopoly,  and certainly behaves like it. 

I see by the statistics that a huge number of people have seen this posting.  Bill Gates,  are you listening?

Update 1-7-14:

These slow/incomplete page-load problems are compounded by out-and-out lies the operating system tells me.  Quite often it tells me that it "can't display this page" when an older machine on the same wireless network and internet service is having no troubles at all,  or at worst shows that Google is just running a little slower than usual.

When it starts behaving like this,  the Windows 8 machine does not spontaneously improve,  no matter how long you wait.  The older machine running side-by-side has no such similar problems.   The only "cure" is a cold shutdown and reboot,  and it doesn't last very long (maybe 2-3 days).  The biggest trouble with restarting is that the Windows 8 machine will actually fail to fully shut down,  even with a power-button "kill",  and actually tries to hide that fact!

I have,  on more than one occasion,  found it running "live",  after I thought I had turned it completely off!

Since the menu shutdown option and the power button "kill" are quite evidently not reliable ways to shut down and restart a misbehaving Windows 8 machine,  I have taken to physically removing the battery to "kill" the thing.  I unplug the charger,  and then pull out the battery.  That "kills" it,  and forces a proper reboot.  So far,  it has worked,  but I don't know (1) how long this will continue to be effective, or (2) what damage this may be doing.

It is absolutely unconscionable of Microsoft to force us to use a product this flawed with their near-monopoly market position.  Windows 8 is more evil malware or virus than it is any kind of an operating system on a non-touch screen device.

If Bill Gates will not come back long enough to clean up the mess Microsoft has made of its Windows business,  then I wish the government would bust them up with the antitrust laws.  One way or another,  the current situation is completely intolerable.

Update 1-9-14:

Functionality interval between shutdowns is now down to 12 hours.  Side-by-side comparison still shows slightly-slow Google on the older machine when this one says the web page is unavailable.  Lies!  Lies!  Lies!

It is time to take this POS back to the store and demand that they make good on it.

Update 1-17-14:

Boots with internet light showing are largely unsatisfactory.  Cure seems to be pulling battery pack until it boots without showing internet light.  Then it seems to get better results,  by-and-large.  Today it took 5 battery pack-pull "kills" during reboot,  before it behaved acceptably.  I started with a normal menu shutdown,  but it did not work right:  told me things I knew were lies.

I am getting the most bizarre "hot key" effects that I did not ask for,  as I type at more-than-minimal speeds.  That's one of the things I really hate about both this operating system,  and this keyboard (which has keys too small for my old,  fat fingers,  and which has a reduced spacebar length,  for no purpose I can understand).

Microsoft,  you should have found this posting by now.  I have seen nothing acceptable from you in the last decade.  Nothing since Windows 98 has been in the least acceptable in terms of usability,  and no version of Windows since the beginning has been stable.  

Toshiba,  I hope you are aware of this post by now.  I have alerted you to it,  in the on-line customer feedback to you.  Fix your damned keyboards.

I would rather go back to DOS than use this f***ing Windows 8.  I hope you lose immense amounts of money on this,  Microsoft.  It would serve you right.

Update 1-25-14:

This has to be the very most unstable version of Windows that Microsoft has ever produced.  Absolutely the worst.  None of them since the beginning have been stable,  but this version makes even the infamous "millennium" version look good.

Basically,  to keep it from bogging down on the simplest task,  I have to restart the computer from a cold shutdown every single day.  Note:  this intolerable trouble isn't malware or virus effects,  I run my anti-malware and "crap-cleaner" software every time I restart.

Otherwise,  without a from-cold restart,  it runs very slowly (interminable spinning-circle "busy  signal") and repeatably fails to load even the simplest internet pages fully.

That last requires multiple refreshes to get a page to load,  not just one refresh.  And,  when it gets like that,  it's past time for a shutdown.  I have learned that.

Problem is,  if you don't recognize this BS in time,  you cannot get it to respond to the keys or mouse for a normal shutdown.  Once that happens,  the battery-pull shutdown is the most reliable method,  not the power button.

It sometimes keeps running and tries to hide that fact from me if I just use the power button.  Because of that weird behavior,  to me,  this operating system resembles a virus more than it does a real operating system.

If anybody out there knows a real human contact at Microsoft,  make that person aware of this customer's extreme dissatisfaction,  would you please?  They do a really good job insulating themselves from their customers.

They no longer do even a creditable job developing useful software.

Update 1-31-14:

One thing I have noticed,  doing side-by-side comparisons between my Windows 8 laptop and my wife's earlier-Windows laptop,  is an unwarranted sensitivity to internet slowness.  Out here in the country,  we have internet service via radio link from a cell phone tower.  Inside the house,  we have a local wireless network.

The wireless network inside the house is just not a problem.  Sometimes the cell phone tower internet bogs down to slow speeds,  and I have complained to the provider about this.  But the point is,  the two computers respond differently to it in the side-by-side comparison,  running the same browsers to the same sites.

I can see this internet slowdown as slower-to-load pages on my wife's machine.  On my Windows 8 machine,  I get very erratic performance,  ranging from "page cannot be found" to "host refused connection" to loading text but not images.  None of these 3 outcomes provide any useful service,  of course.

Images that fail to load usually will not load with a refresh,  either.  And if you keep trying to force the image load with refresh,  the software will lock-up,  requiring a shutdown and reboot.  Odd that the older,  supposedly less-capable machine has far less trouble,  isn't it?

I must therefore conclude:  it ain't the chip in the machine (all of those are pretty fast now),  it's the operating system.  Windows 8 just does not work as well as earlier versions.  Given the size and resources of Microsoft,  and the longevity of the basic Windows operating system concept,  there is absolutely no excuse for the problems I am experiencing with "unusable internet",  when older machines still function.

And that is what I am complaining about.  That is what I object to most of all.  That is why I say that Windows 8 sucks!

Update 2-3-14:

The most effective,  least risky procedure I have so far discovered is cold shutdown after no more than 24 hours of continuous operation.  I do this from the normal menu with the charger unplugged,  but,  after it shuts down,  I pull the battery pack to make sure it really stays shut down reliably.  I leave it cold like that for several minutes to several hours,  just to make sure everything internal has fully discharged.

This procedure seems to work reasonably reliably,  although on occasion I have to do it twice before I get a "good" boot-up.  A "bad" boot-up shows up most distinctly as very erratic operation of the browser,  before one even tries to open pages on the internet.  That's very definitely a software problem inside the machine,  not anything to do with internet service connectivity.

If Microsoft had done their job properly developing and de-bugging this Windows 8 operating system,  I would not be experiencing these problems.  I would just merely be pissed off at useless and unfamiliar screens trying to make my laptop look like a touch-screen Apple device.  If I had wanted a touch-screen Apple-like device,  I would have bought one from Apple.

Microsoft has been a de-facto monopoly in non-Apple operating systems for a long time now.  They certainly act like it,  too.  Does anyone else wish Uncle Sam had broken them up?

Update 2-5-14:

So far so good with the procedures adopted per my 2-3-14 update just above,  except:  sometimes Google Chrome very most definitely fails to load in a working condition,  upon reboot.  It takes another cold shutdown to correct this!

That has to be fundamental software incompatibilities between Windows 8 and the Google Chrome browser.


Microsoft's forte was always supposed to be its connections to the internet,  its ability to make browsing easy.  This is especially supposed to be true with the new tablet/desktop hardware and Windows-8 operating system that is supposed to compete with Apple.

Looks to me like it's actually a failure.  At least,  for ordinary non-touchscreen laptops like mine.

Update 5-7-14:

If there's anything I hate worse than Windows 8 (and the above text indicates the EXTREME depth of that hate!!!!),  it's my internet service provider of the last few years: Skybeam.  They had a monopoly out here in central Texas,  and they certainly have acted like it.  I have NOT received the service I have PAID FOR,  for the last several months,  at least.  

That's theft!

These bastards have been a monopoly out here in the boonies of central Texas,  until recently,  and they have certainly acted like it.  I am firing them in favor of the ONLY other provider who has showed up in the last several months,  a provider who guarantees connectivity without "data capping".  

If anybody else has had any sort of experiences with Skybeam,  I really encourage you to comment on this article! An awful lot of people visit this site!  It WILL be seen!

My experiences with Skybeam,  since about a year or so ago,  have been uniformly,  and very egregiously,  bad! Dial-up is faster and more reliable than Skybeam!  If you are served by these charlatans,  I recommend firing them!  As soon as you possibly can!

The more folks fire these bastards,  the sooner they will get the message to transform into a customer-oriented business.  They are so very clearly NOT that kind of business right now.  Money talks.  PLEASE fire them!

All else I can say is this:  if you can possibly avoid doing business with Skybeam,  then avoid it!  DO NOT DO BUSINESS WITH SKYBEAM!  You will be sorry,  if you ever do.

Skybeam sucks!  Worse than Windows 8 sucks! 


Update 5-15-14:

We fired Skybeam yesterday,  and hired Air Net as our new service.  Their service is far better,  for only a little more price.  It's nice to have a choice.  Monopolies are bad.  


Update 6-22-2016:  

The new internet provider Air Net has given us far better service than Skybeam ever did.  Sometimes it fails in a storm,  but service is usually restored within minutes to hours.  And it's always much faster.  

My Toshiba laptop died of old age mechanically.  The hinge connections failed.  Plus,  the labeling wore off all the keys.  It's hard to type when you cannot see what key it is you are striking.  I had just replaced its battery pack when this unfixable crap with the hinge occurred.  That pretty much settled it.  

I replaced it with an ASUS laptop originally intended for my wife.  The new laptop works OK,  except that it cannot in any way tell me when the caps lock key has been hit.  No light,  no indication on the screen,  nothing.  It is a very irritating problem.  

What this new laptop lacks is a way to pull the battery to get a certain "kill".  I REALLY do not like that!  The battery is utterly buried within somewhere.  So far,  the power switch "kill" has worked when I need it,  but I would really and seriously prefer to have a battery-pack "kill",  as I fully expect this thing to learn how to ignore a power-switch "kill" the same way the old Toshiba did.  It already ignores me if the charger is plugged in,  just like the Toshiba.  

This thing came from the factory criminally mislabeled:  its label says it's a Windows 8 machine,  but after considerable looking around,  I was able to confirm it is really a Windows 10 machine.  Microsoft really hid the descriptions that tell you what your OS is.  I hate them for that,  forever!

Bottom line:  Windows 10 sucks even worse than Windows 8!!!

There is nothing about it that is in the remotest-sense stable,  and it is even less compatible with other Microsoft products than was Windows 8.  It will not even boot-up correctly about half the time!  And I am clogged and bogged-down with touch-screen crap that I cannot use!  Almost useless.  DOS was far better,  as hard as that was to use.  

This thing randomly bogs down and refuses to "see" keystrokes or mouse clicks,  unless I hit the devices really hard,  which greatly shortens their lives.  I have the worst problems with Microsoft Office 2007 (which is what I had available to load),  but I have seen it do the same idiocy in non-Microsoft software.  Just not as often.  

My typing speed is reduced to 1 single character every second or two when this occurs.  I have to hold the key down for most of that time,  for the keystroke to "take".  Whatever is going on,  there's no indications on the screen or anywhere else.  This is just totally unacceptable.  

Microsoft:  incompatibilities like that are unconscionable and proof of criminally-negligent incompetence.  I wish someone would "nuke" you.  

I will never,  ever buy another IBM-clone PC that runs on Windows.  

I don't know anything about Apple.  Makes no sense to me at all,  never did.  Maybe Unix?


Sunday, November 17, 2013

Rocks From Space

The recent space object that exploded over Chelyabinsk caused a lot of damage and injuries,  and it could easily have been a lot worse.  This provided a loud warning that got some public attention. 

Since then,  back-page stories have documented several close passes of “extinction-event” and “city-buster” sized objects.  Some of these were seen coming,  some were not. 

Update 4-6-14:  Detection of 1+ kiloton explosions by the nuclear test detection network is attributed to asteroid explosions in the air (bolides),  similar to the Chelyabinsk object.  The frequency of these detections suggests that asteroid impacts upon the Earth are 3 to 10 times more frequent than previously thought.  The vast majority are not detected during approach.  This has serious implications:  these "city busters" are not busting cities merely due to blind luck (not exploding over a city).  

Another story that barely made the evening news was a re-estimate by the experts that the risk of “city-buster” objects was very likely some 7 times higher than previously thought.  Chelyabinsk-like incidents seem likely about every 2-3 decades,  not every century,  just not always over cities.

The clear conclusion:  it is indeed prudent for mankind to address this threat,  now that we are both aware of it,  and technologically capable. 

For the last several years,  there has been an ongoing ground-based sky survey that has found about 90% of the threatening objects of “extinction event” size.  The idea is find them years ahead of any risk they might pose,  so as to enable intervention by some sort of deflection technology.

This kind of ground-based telescopic survey simply cannot see the smaller “city buster” objects until they are very close,  if at all,  for a variety of technical reasons.  There are hours of warning at best,  and for the Chelyabinsk object,  no warning at all because it came at us “out of the sun’s glare”. 

The B612 Foundation has as its mission protection from asteroid strikes.  They have proposed a satellite (or better,  several satellites) located near Venus,  to look outward from the sun for “city busters”.   

This kind of space-based sky survey is technologically feasible.  It would enable years of warning for objects this size. 

Problem:  there are no such satellites,  and nothing is funded to build and launch any.

The objects smaller than “city busters” are thought to be vastly more numerous.  With the kind of technologies we have,  these are unlikely ever to be seen,  except at really short “duck-and-cover”-type warning times,  even with satellites in space looking. 

Update 4-6-14:  B612's Sentinel detector satellite is still unfunded by NASA,  relying entirely on private contributions.  It is thought to have a cost near $400 million.  This is to be an infrared detector looking outward from the orbit of Venus,  and should be far more capable at detecting small asteroids,  even those closer to the sun than Earth,  than any optical telescope survey from Earth (which is blind in all directions except outward away from the sun).  

Problem:  there is no organized way to get a timely warning out,  even within national borders,  much less internationally.

What is needed immediately:  satellites for the “city buster” search,  and an organized international “duck-and-cover” warning system. 

What is needed longer term:  what do you do with your years-of-warning?  How do you deflect threats?

There is no real agreement among the experts on the internal nature of such objects.  History says it is likely that what they do think,  is incorrect.  And,  it is extremely unlikely that remote observation will ever resolve the internal structure question. 

The internal structure and properties of these objects fundamentally controls their response to proposed interventions.  What we do know says the movies are wrong:  you don’t blow them up,  you have to push them aside.  Blowing them up,  especially at the last minute,  would actually make the damage worse (shotgun blast versus a single bullet strike). 

Problem:  we already know they are not all the same in their internal properties. 

We know that the few monolithic rocks survive atmospheric entry to hit the surface,  if larger than a green pea.  Baseball size,  they hit with a really damaging whack.  Basketball-sized,  they start blowing big craters like bombs. 

Most of these objects seem to be internally fractured,  or even just rubble piles very loosely bound together.  These are the “bolides” that explode during entry,  the bigger ones with the force of very large nuclear weapons,  like Chelyabinsk.  Bigger also generally penetrates lower down before exploding,  depending upon how tightly the chunks are bound together.   

So,  how do you push on something that might fly apart at a touch?  In our best guesses,  most of the time,  that’s what you are faced with.

What Do We Need to Do?

Developing deflection schemes will fundamentally require in-situ investigation,  to include looking deep inside these objects to find out how,  and how tightly,  they are bound together.  This can be done with robotics to a point,  but men will have to go eventually.

We will need experimental trials of different deflection techniques.  Again,  this can be done with robotics to a point,  but men will have to go eventually.

Fact:  this ain’t like going to the moon.  This is months-to-years in space (like Mars),  not days.

So,  what about NASA’s latest plan for capturing a small one for return to near-lunar space where we actually can send men?  Two problems:  (1) the single captured object is unlikely to be representative,  and (2) this does not address the technology we need for long-distance manned travel. 

If instead you develop long-distance manned travel,  you kill two birds with one stone.  First,  you enable the necessary manned missions to many different asteroids.  Second,  if only you add a lander,  you can also go to Mars.

So,  what is the smarter space program to have?

Satellites inside Venus to look for city busters.

Set up the warning system for the small duck-and-cover objects.

Work intensely on the fundamental requirements for long distance manned travel;  these are (1) better propulsion,  (2) protection from radiation, (3) sufficient living space properly distributed,  (4) artificial gravity by spin to prevent microgravity diseases,  and (5) adequate long-term food preservation.  Update 11-21-13:  see "Details" below for a description of these 5 enabling items for long-distance manned travel.  

And what are we doing?

A giant rocket we may not even need,  which is based on legacy technology,  the manufacture of which is sited in powerful congressional districts,  and the need for which is mandated entirely by congress.

A capsule capable of days-to-weeks of manned travel to and near the moon,  but completely inadequate for months-to-years in deep space,  with extremely-limited radiation protection capability. 

A space station without a medical centrifuge for finding out “how much artificial gee is enough?”,  but which did teach us (1) how to build things from smaller payloads launched by multiple smaller rockets,  and (2) microgravity diseases will prevent manned travel longer than a year or so,  if we go without artificial gravity.

Some support for three commercial ventures aimed at manned launch to orbit.

None of the other critical enabling items for long-distance manned travel are supported.

None of the enabling satellites for city-buster warning are funded in any way.

No duck-and-cover warning system is being funded,  much less actually organized. 


Write your congressmen and senators about this.  Write the NASA administrator about this.  I do,  but I am just one voice. 

Footnote added 11-24-13:  

A version of this article appeared in the Sunday "Waco Tribune-Herald" newspaper.


There are other articles related to asteroid defense that I have written and posted on this site.  If you click the keyword "asteroid defense",  you will see only those articles.  Otherwise,  use the by-date/by-title navigation tool to quickly find them.  My exact recommendations about what to do have evolved a little over time,  you can see that in the various articles.  They are as follows:

11-17-13  Rocks From Space  (this article)
 2-15-13   On the Two Dangers From Space
10-31-09  The Future of NASA Manned Space
7-22-09    On the Future of the US Manned Space Program
4-21-09    On Asteroid Defense and a Good Reason for Having National Space Programs (***)

(***) In point of fact,  I did attend the first IAA international conference on asteroid defense in Granada,  Spain,  April 26-30,  2009,  and I presented a paper there,  shortly after writing this article.  My paper was on electrostatic attraction as an upgrade to the basic gravity tractor asteroid deflection concept.

I got to spend some time with many folks at that meeting,  including ex-astronaut Rusty Schweikart,  and ex-cosmonaut Dumitru Prunariu.  Schweikart was on Apollo 9 and was until recently head of B612 Foundation.  Prunariu was (at least as of 2009) head of the Romanian space program,  supplying cosmonauts (and more) to the Russians.  He flew on Salyut 6,  if memory serves.  I also spent some time with Mark Boslough of Sandia Labs,  who is the bolide explosion expert that most folks call upon.

Update 11-21-13:  Details of the 5 Enabling Items for Long-Distance Manned Travel

(1) better propulsion:  we need higher specific impulse,  but we need it at high thrust levels,  enough not to incur long burn time gravity losses (as with all ion and plasma thrusters today).  It would be nice to have a long-term storable version of liquid hydrogen technology.  We need a megawatt-level flightweight electrical power supply for ion and plasma rockets (such as VASIMR).  I would definitely resurrect and improve the solid core nuclear thermal rocket technology,  that almost flew 4 decades ago.  I would work really hard on bringing gas core nuclear thermal rockets to testable forms.  I would resurrect and improve the old nuclear pulse (explosion) propulsion technology that we know would have worked,  but which we never developed. We also need much less expensive launch to Earth orbit,  at the largest payloads that have commercial need. 

(2) protection from radiation:  there should be a unified standard on how much of what types of radiation are allowable.  This is needed for exploration astronauts,  and for long-term settlers,  and their children.  There should be some experiments done very soon in very-high Earth orbit,  to test and develop water/wastewater tankage as a shielding concept that we could implement in the design of any manned interplanetary vehicle.  These standards will always be empirical best guesses;  we need to recognize that,  and "just get on with it".

(3) sufficient living space properly distributed:  this is an under-represented / too-often-ignored issue,  in too many of the mission designs I have seen.  It is a critical issue,  ask anyone who has ever served time in solitary confinement.  The volume / person ratio is NOT the only thing to consider,  but that number should be minimum around the ISS value,  and should more properly look about like what we flew in the old Skylab station.  The distribution and use of that volume is also critically important.  People need more than just their sense of personal space.  They need both a place to congregate,  and a place to be alone.  That second factor is actually the more neglected of the two.  

(4) artificial gravity by spin to prevent microgravity diseases:  for missions over about 1 year,  this is simply required,  and we might as well face it.  The only physical principle we have for artificial gravity is centrifugal force.  There are two issues with that:  (1) how fast a spin is tolerable to the balance organs,  and (2) how much artificial gravity is enough?  The answer to spin rate is a fuzzy empirical value in the neighborhood of 4 rpm for ordinary folks.  We have never run the experiments to find out the answer to "how much gee is enough?",  and we did not equip our ISS to find out.  

So,  since we evolved at 1 gee here on Earth,  that's the design value,  until and unless someone runs the necessary experiments to find out the therapeutic value we really need.  And bed rest experiments won't find it,  they are a poor analog at best.  For 1 gee at 4 rpm,  you need a 56 meter spin radius.  You do NOT need to build a gigantic and super-expensive ship for that.  You do NOT need a Rube Goldberg contraption of cable-connected modules for that (an accident waiting to happen).  

Build your vessel of modules docked in orbit,  to form a slender baton shape.  Put your astronaut habitat at one end,  and something heavy (the engines) at the other.  Spin it end-over-end.  It's perfectly stable,  as seen in Friday night football games all over America.  You'll find you have no need of a gigantic launch rocket to send them up individually.  It's exactly how we built the ISS.  

Artificial gravity simplifies all sorts of life support issues back to things we already know how to do.  Water and wastewater treatment,  toilet design,  cooking,  bathing,  and proper / effective exercise all depend fundamentally upon gravity in one way or another.  So also (most likely) does successful completion of a pregnancy.  

(5) adequate long-term food preservation:  astronaut "space foods" are the plastic-bag analog to the same canned goods we use down here.  Trouble is,  they don't last as long as the canned goods we are used to.  About 12 to 18 months is their maximum lifetime.  A trip to Mars is 2.5 years in space,  so there's a real problem with food.  

Down here,  we have long solved that problem with real canned goods and frozen foods.  These store for decades,  if not centuries,  but often require meal assembly and cooking processes involving free-surface liquids to produce things that are palatable.  Those cooking processes require gravity,  but we need that anyway!  

Until and unless we find something better,  we will have to use the heavier frozen and canned-good foods.  Fresh foods will require a garden,  and most of what we know how to do in that topic also requires artificial gravity.  

Update 3-12-14:

More Space Rocks --

There were three close asteroid fly-bys in just two days recently.  We get several of these each year,  that is normal.  But 3 in 2 days really is a little unusual.  The warning time with all of these was days or less.  This is a strong hint of a real risk,  one so far mostly unaddressed by humanity.  

The data are tabulated just below.  For reference,  the Earth-moon center-to-center distance is 385,000 km, and the Chelyabinsk object was about 15 meters in size.    

8-meter 2014 EC,  Thursday 3-6-14,   61,600 km miss distance             
30-meter 2014 DX110,  Wednesday 3-5-14,  350,000 km miss distance
10-meter 2014 EF,  Wednesday 3-5-14    about 120,000 km miss distance

Two More "Enabling Items" --

In addition to the 5 "enabling items" listed above to enable long-distance manned space travel,  we also need a supple space suit,  and a way to build in orbit things too large to fit the payload shrouds of our launch rockets.  Both of those get addressed in "On-Orbit Repair and Assembly Facility",  dated 2-14-14.  That includes some good photos of two very good spacesuit prototypes.  

A Place to Safely Test Nuclear Propulsion -- 

We could also use a good,  safe place to test nuclear space propulsion.  That place should provide an easy way to avoid air and water pollution,  and a way to avoid annoying neighbors.  This is especially important with nuclear stuff,  since both routine operations and the inevitable testing mishaps will involve radiation.  

I suggest the moon.  There is no better reason to go back.