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I read your May 2003 Popular Mechanics article on pages 110 to 113, titled America's Space Program: What Should We Do Next, and I'm impressed with your report that what I call Backup Recovery Mode is being worked upon (although survival of a catastrophic breakup is not described.) I'm sorry to say that I'm not impressed with the rest of the article.
"A high-priority, similar-designed crew-return module also could solve the crew-staffing problem aboard the International Space Station (ISS). Currently the station is limited to three the number of people that can escape in the Soyuz capsule."
Titanic's lifeboat could only carry only 65 passengers, yet 705 survived, what's up with that? Obviously, Titanic carried more than one lifeboat, and the same rule can also apply to the International Space Station without designing a new ship for the job. In the 1991 Options (details on http://www.abo.fi/~mlindroo/Station/Slides; oops...1993 Options!), the three concepts all clearly displayed two Soyuz lifeboats, good enough for a crew of six. Three are good enough for a crew of nine, and 20 are enough to carry 60 crewmembers home. Also, having one to spare is advisable, in the case that a lifeboat fails or is inaccessible during the emergency (this happened on Mir, by the way: a fire blocked the hatch to the Soyuz, fortunately, the station and crew survived.) A larger lifeboat with single digit numbers of crewmembers is inadvisable, given that the Soyuz has proven sound over it's 35 year history, with two launch aborts that the crews survived, and two entry accidents with a total of four casualties. This compares favorably with the Shuttle, and its 14 astronaut casualties.
"I believe that lunar missions could lay the groundwork for Mars missions."
I believe that lunar missions could delay the groundwork for Mars missions. Have you read The Case For Mars (Zubrin & Wagner, The Case For Mars, The Free Press, 1996)? This book details the practical and engineering reasons why this is not the case.
"The third destination could be an asteroid -- In fact, this could be an attractive, early public commitment."
This tells me you have probably read Robert Zubrin's Entering Space: Creating a Spacefaring Civilization (Penguin Putnam 1999) which details the "GaiaShield" mission. I doubt many have read Entering Space without noticing the many times it mentions The Case For Mars. Finding the above two statements adjacent to each other is a surprise to me. We do agree that humanity should visit Mars. We do not agree on the mission profile.
"I absolutely agree with the idea that when humans go to Mars, they should first go to the moons of Mars, not the planet itself."
I don't. Whose idea is that anyway. The Case For Mars shows how return propellant can be made on Mars, so that it does not need to be carried along, saving some 90% on mission mass to the surface. A landing on the moons of Mars would reduce mission delta-v, but not give you the return propellants, still leaving you with a heavier, more expensive, and less fruitful mission. For the ordinary reader, whose head all of this technicalese went over, imagine you are driving to a relative's place in the suburbs of a distant city with gas stations only in the city's downtown, and your car's tank only has enough gas to make the trip one way. Would it make more sense to carry the return fuel with you on a tank on the roof, or to make the short trip from your relative's to the city's downtown gas station to pick up gas, especially since the primary reason is not to visit your relative, but the city. Buzz, I just don't get it, could you explain why this is in any way better?
"[In an emergency] From the surface of the planet you would have to lift off, get into orbit, and rendezvous with a spacecraft that could bring you back."
There is no orbital rendezvous required in Mars Direct plan presented by The Case For Mars, the return vehicle launches directly from Mars to Earth. This demonstrates a lack of understanding of the plans presented by the competition to the plan to land on the moons first.
"It is critical that we not go to Mars unless we are committed to a gradual, evolutionary buildup of a permanent base. We should not go once, twice, or three times and then say we have done it and end exploration."
I'm writing from a perspective of someone born in the shuttle age, not one who has landed on the Moon, and then watched my beloved space program retreat to LEO and then destroy itself in fireballs over the Atlantic and Texas because its country sat on its laurels and lost its vision. But even as someone born in the shuttle era, I still cried over Columbia STS-107, and I wholeheartedly agree that if we go to Mars, we should stay. The Case for Mars and Entering Space both present a progressive approach to spaceflight, starting with near milestones and establishing there to move on. The numbers don't say we need to go to the Moon first. And also, The Case For Mars does support the construction of a Mars base. Is this another point lost because you have not read it?
pp. 110 "A high-priority, similar-designed crew-return module also could solve the crew-staffing problem aboard the International Space Station (ISS). Currently the station is limited to three, the number of people that can escape in the Soyuz capsule. ... Modules could be transported to the ISS inside the shuttle cargo bay or launched unmanned atop a Delta 4."
pp. 113 "NASA must resist the temptation for a quick fix, such as building a space plane that serves as a taxi to and from the space station on expendable launch rockets."
It would appear that you are talking about the Orbital Space Plane (OSP) here in both quotes, one for and one against. The OSP is a proposed crew ferry to the ISS operating from Delta IV rockets, capable of both manned and unmanned operation. My idea of launching Delta Sprint from a Delta 7925 rockets similar to the one that launched the Mars Odyssey is an expression that the OSP as a quick fix is not quick enough ... the Delta IV has not flown yet. It would be better to say "NASA must resist the temptation to stay with the quick fix..." like it did with the partially reusable Space Shuttle, which has turned into the least efficient launch system in the history of spaceflight, hauling 60 tonnes of wings, wheels, and thermal protection system aloft just to make spaceflight look routine, an actual complaint about the Apollo era. Before we get spaceflight that is actually routine, we need fully reusable launch systems, you have only expressed this need in the illustrations of Starbooster 30, of which I was not previously aware and have no technical details of (including whether or not it is fully reusable...it does not appear to be.) I think also, that spaceflight to LEO needs to be routine before we can go to Mars, simply because the numbers say that getting to earth orbit is half the trip.
You, Mr. Aldrin, are a more influential voice than the sum of myself, Mark Wade, Marcus Lindroo, and Robert Zubrin. Please, I beg you, get The Case For Mars, read it through, visit my web site, , learn about the concepts that compete with conventional NASA thinking. Please visit http://www.astronautix.com, and learn about the concepts that competed to go to the moon as Apollo, besides the one you flew on; learn about the concepts that wanted to be the Shuttle, besides the one that broke up over Texas. Then, armed with this new information, and your experience from Apollo, ask yourself What Should We Do Next? again. I doubt the answers will be the same.
Terry Wilson
aftercolumbia.tripod.com
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