Saturday, November 8, 2014

Destination Not Mars

Mars remains the beacon for human exploration. Generations of science fiction writers and multiple successful space probes and rovers have established Mars in the core of our collective consciousness. More than any other place, Mars beckons humanity. Although an eventual human landing on Mars is inevitable...
This is not how this article begins. Instead it is used as the transition to its argument for focusing on Deimos as the intended destination. It is just one of many articles you can find that attempts to dissuade us from colonizing mars with one distraction or another.
...most experts agree it is currently a bridge too far.
Stuff those experts. I'll raise you reality. Nothing ever gets done until someone does it. Taking focus away doesn't get it done. If you want to explore Deimos, fine. Explore it. But don't kid yourself this is the path to colonizing mars. The path to colonizing mars is to get colonists on mars. Now back to the start...
Round-trip crewed missions into orbit about Mars are beyond the reach of current capabilities—but just barely.
While I'd like to put a bullet in this carefully worded meme, until we've actually done it, no proposal can ever argue as forcefully as actual performance. Instead of begging the government for handouts, for $200m, funds which Tito already has, he could have put an unfueled Inspiration Mars ship in LEO... capable of taking not just two, but up to a dozen, on a mars flyby. Then he could be spending his time working on getting funds for an existing ship in orbit rather than having nothing to show a potential investor other than good intentions. The fact is, a round trip crewed flyby around mars involves not a single thing we haven't already done in parts. So to say we are incapable is farcical.
...extending human space travel from LEO to interplanetary destinations, we face difficulties no less formidable than did Magellan.
Is this assertion true or are we just supposed to accept it? We have a huge advantage over Magellan. For Magellan, "Here be monsters" was the reality of his lack of knowledge. They were facing an unknown, unknown. We today are not. We lack experience but we have knowledge. That lack of experience could kill us as easily, but we can also anticipate and avoid problems just by putting effort of thought into it before we go. Not only that, but we can gain much of that experience before we go. Any ship going to mars would benefit from shakedown cruises (around the moon?) first. These cruises could even be a source of profit that pays for the fuel for the mars mission. Are you paying attention Mr. Tito?

Finally we discuss Deimos. Is it a natural staging area for mars? Although probably not his intention he first shoots down the moon as a staging point...
Deimos is easier to get to energetically from LEO than the lunar surface.
Yes, indeed. It's  also part of the logic that destroys the Conestoga wagon and island hopping analogies. If it's not your destination, stopping for fuel can raise time and cost in frictionless space. For space travel the question is, "Do you have enough resources for this leg of the journey?" If you do, any other stop from that leg is an undesired cost. Which includes Deimos since it also cost additional fuel to get to than just going to [a better] orbit, leaving the question, does it make up for this starting disadvantage. Let's look at those he gives? First he sets up an artificial condition...
If several surface assets were positioned at regularly-spaced longitudes...
The first landing will be at one spot, making a stationary orbit (geosynchronous) preferred. For about the same cost (except lower in cost per crew) instead of the Mars One plan of sending all four to the surface and waiting 26 months for more help, you put a dozen in the right orbit with multiple landers (which arrived in mars orbit on a separate low cost trajectory) taking 2 to 4 crew to the surface at a time when you need them instead of having them years away (and unable to help in a timely manner.) Working in shifts, those in orbit work continuously to assist those on the ground. Those on the ground can then make those telerobots more productive especially to get beyond snags that will occur. There simply is no other comparably productive scenario. He makes my argument for me...
Phobos is so close to Mars it unfortunately has a much narrower view of the planet. Because Phobos rises and sets four times a day, acquiring and operating surface assets from the inner moon would be much more challenging than from Deimos.
...and less challenging again for a ship in the right orbit which also cost less to get to. We've taken away the base camp argument because Deimos is the wrong base camp.

Deimos is not a staging area for the landers that are currently being designed which use the wrong fuel and are not refuelable. So do we stop colonization until the mars SSTO is available which requires a brand new development program (Bezos perhaps?) Mars One already has SpaceX landers in its critical path suggesting development is farther along than us mere mortals are privy. We do have the preliminary specs. $150m for 2,500 kg. including up to 4 crew.
[Deimos ISRU could make] human missions to the Martian surface far sooner than anticipated.
Not by my anticipation that doesn't require this, what if? It is worth looking into this, but is just a mistake to impose on a critical path when it is not required.
...the standard approach [is] insufficient for human interplanetary spaceflight, it is dangerous.
Nobody is denying the danger. Deimos does not mitigate it. This assertion is simply false because we've already demonstrated it is sufficient. We just haven't put all the pieces together in a single mission yet to unassailably prove it.

Am I forgetting radiation shielding? No, I am not. It would take time to establish a base on Deimos. That time is better used setting up the first ISRU habitat on mars itself. Part of the crew might spend an extra month in orbit while risking no more than Mars One plans on the surface. They join those on the surface and the ship (or ships) return to earth for reuse.
For trips to the Mars system and back including required stay times, self-contained exploration systems are simply not possible.
A true statement and strawman (or false choice) since that is not my proposal. I think Mars One plan must be modified but including Deimos is just a costly distraction. Note that trips back are not part of either proposal but can be implemented with an optional ERV without modifying either plan.

Now it's revealed that Deimos is an even bigger distraction than even I suggest...
Establishing a human foothold at Deimos will require a series of increasingly sophisticated robotic precursor missions with probes capable of everything from detailed mapping and remote sensing of the moon to multiple sample analyses of surface and subsurface strata, excavation and preparation of a radiation-protected subsurface habitat (see below) and storage facilities for pre-emplaced crew consumables, and Earth return propellant for visiting crew. Support infrastructure (e.g. power, communications, thermal control, refrigeration, environmental control, and life support) must be transported, deployed, and proven operational prior to human visitation.
Whoaa... perhaps we should first establish a base on one of Saturn's moons to show we could do it on Deimos. A ridiculous suggestion, right? You bet and no less than this. Any chance of arguing that Deimos is not a distraction just died with this factual statement by the article.

With all due respect to the authors of this fine article they destroy their own argument. Perhaps if they had less integrity they could be more persuasive? I was going to wait for part two, but I will address it here after it comes out.

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