Posted on 01/24/2005 6:19:49 PM PST by KevinDavis
There has been no shortage of ideas of how to send humans to Mars. From the Battlestar Galactica spacecraft of NASAs Space Exploration Initiative 15 years ago to Robert Zubrins Mars Direct concept to high-speed alternatives powered by Franklin Chang-Diazs VASIMR engine, there have been plenty of proposals for mounting manned expeditions to the Red Planet, with varying flight times, crew sizes, and, of course, costs.
(Excerpt) Read more at thespacereview.com ...
Please send Christiane Amanpour first.
Bump to read later
Both the $500 billion Battlestar Galactica and $30 billion Zubrin models still entail a cost of $5-12.5 billion per astronaut. I happen to support the Zubrin model of the two but believe the smartest way to go to Mars would be to go to an inbound carbonaceous chondrite Apollo NEA with an aphelion within the asteroid belt.
The advantages of this strategy are numerous:
1. Lower delta-V,
2. Travel duration is much shorter,
3. The asteroid can be mined for water, oxygen, hydrogen, nitrogen, carbon and other materials needed for the construction of additional spacecraft, greenhouses, solar panels and foodstuffs,
4. Habitats can be placed below the surface of the asteroid, protecting the inhabitants from solar flares,
5. Construction for future residents can be done throughout the voyage,
6. Can be resupplied and provided with new or replacement crew on the outbound leg,
7. Will enable the insertion of materials and supplies for future spacecraft in earth orbit,
8. Will allow for hundreds if not thousands of researchers, scientists, miners, astronauts and colonists to go to Mars and the asteroid belt for minimal cost of only several million per person.
In essence, the difference is the creation of a fully functional railroad with a train containing thousands or a wagon with several astronauts for the same price.
Think of how the West was changed by the railroad ...
Riding an NEA makes sense, but how vulnerable is this scheme to an argument like the public vs private transportation choice? I mean, "how often do the asteroids run" to where you want to go, and pretty close to when you want to go?
The orbits of hundreds of NEA have been plotted for a very long time. All that really needs to be done is select the ideal candidate from the hundreds of Apollo NEA above 1 km in diameter and determine its course. It also won't be too much of a problem trimming the orbits of the NEA cyclers into desired orbits by mass launching.
If this approach is taken, it won't be long until many cyclers in metastable orbits will be shuttling people back and forth between earth, mars and the asteroid belt.
I mean, if we're really smart, we can place multiple cyclers on the same orbit but equidistant to one another and also have multiple orbits. Heck, 192 cyclers in eight orbits of 24 each will have one cycler going to mars every other day. Interplanetary travel then becomes ridiculously easy.
This same principle can apply to an earth-moon cycler placed in HEEO. If the perigee is 1,000 km and its apogee is 407,000 km, it can be made to have an orbital period of only four days. Thus, anyone going to the moon only needs to be boosted to leo of 1,000 km. They go to the cycler and spend the next four days coasting to the moon. Having 12 cyclers in equidistant positions will create a stable transport system to and from the moon every 8 hours.
step 1) forget Mars: seeing whether or not water is really there is no big deal
step 2) concentrate on existing on the Moon first - AND the problems inherent with living in space long enough to GET to Mars
step 3) after you're able to do all of THAT right, THEN think about going to Mars
Figure it: didn't your parents make you camp in the backyard a number of times BEFORE they let you go off and climb the mountains?
If we accept the orbits as they are, how many suitable candidate NEA do you think there would be ?
well, we do know from Spacewatch that there are at least 2,000 asteroids larger than 1 km in diameter that crosses the earth's orbit. Furthermore, those with a diameter above 100 meters amount to 500,000 near earth asteroids (NEA).
IOW, an awful lot of asteroids to hop a ride on to Mars and the Belt.
bout time
Sadly, America no longer has the industrial base, nor the "manifest destiny" willpower to undertake such an endeavor.
The moon has no atmoshpere and no water. It does apparently have an abudance of the Helium-3 isotope, which could be used as a future energy source. So the moon should not be neglected, but neither should it take precedence over creating an inhabitable climate on Mars.
Of course, this really doesn't matter, since this country no longer has the ability to undertake such a long-term and expensive project.
Thanks - good info!
Mars' atmospheric pressure is between 7 and 10 millibars (.07%-.10% of Earth's pressure at sea level) and is 95% CO2. IOW: not enough of an atmosphere to make a difference. And the determination of water is still a 'maybe' (no direct evidence of water; just interpretations that "thus-and-such could've been caused by water" - COULD HAVE).
Also, if you're living off-earth and get your "@$$ in a crack" (so to speak) would you rather be 6 months away from Home and Help, or 3 days? Given that stepping outside your shelter on either body will result in immediate asphyxiation and freezing.
IMO: Lunar benefits outweigh Martian benefits when you consider the immemdiate uses to Earth: a stable platform for environmental observation, communications, radio astronomy, and so forth - all in all, a better, more convenient place to 'learn' how to live off-world before making the attempt far away.
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