New Mars Forums

Also, the Shuttle's fuel tank can only keep LH2 cold for hours, not days or weeks as would be necessary with a spaceship or fuel storage depot.  LH2 is very difficult stuff.  TAnks have to be pre-cooled before LH2 is pumped into them or it will flash into gaseous hydrogen.  Some LH2 is sprayed into the tank to cool it and the gasified hydrogen is collected and reliquified, thereby complicating and adding expense to the whole thing. Then the LH2 is pumped in.  Special plumbing and fitting are required.  Simple plastic hoses will work with water.  I say- SAY NO TO LH2 WHENEVER YOU CAN.

here's a good moonbuggy page with picture of the wheels made from spring steel with titanium cleats shaped like chevrons.   http://www.hq.nasa.gov/office/pao/Histo … h23-3.html

I vote for moonbuggy style wheels on land rovers with 2,3,4 or 6 wheels and tracks for heavy mining equipment

I 've always liked the simplicity of water/NTR  Here's a great site: http://www.neofuel.com  Water presents no boil off problem.  It can be stored in a plastic bladder rather than a heavy fuel tank and this makes very high mass ratios possible, so high that water actually gives better performance than LH2 does despite the lower ISP.  Using water straight in a NTR elimates the need for electrolysis and cryogenic equipment and associated power supplies.  Less mass, less cost, simplicity=reliability The only problem is getting around those who will forbid the launching of anything nuclear.  I've tried to say for a long time that if a nuclear reactor crashed on land it would bury itself in a crater under 30 feet of dirt and anybody close enough to be exposed to radiation will be close enough to be killed by the impact, so why worry??  If we don't use nuclear power to get a foot hold in space and tap energy in the form of 3he and SPS or LPS, we will be forced to use nuclear power on EArth longer and that will entail more risk.

here are some ideas you can't miss: http://www.spaceislandgroup.com/dual-launch.html
They want to stick a modified DC-X on a SDV.  Cool idea.

Nuke the polar caps?  Too much radioactive waste.  Or do you mean divert an asteroid onto collision course with the polar caps?  What about explosive blow off?  Better use lots of little impacts. Think shotgun instead of cannonball.

And for all the space elevator fans out there, one of the moonlets could serve as ballast.  You need a heavy ballast for a workable space elevator.  If the moonlets are C-type they might serve as a source of carbon for the cable.  Moreover, Mars orbit is not littered with thousands of pieces of space junk that could crash into the elevator.

The SDV works just fine for me.  We can use the ETs in orbit for many purposes.  With the longest carbon60 nanofibers being only 20 cm long, a far cry from 22,400 miles, I think we'll be using rockets for a long time.

If GOM wants to discuss religion, there is the Civilization and Culture section.

I feel insulted by GOMs inapproprate introduction of religion into an otherwise scientific discussion.  If you really want to be fundamentalist, there is no martian future, just the apocalypse.  Such superstitious hogwash. 

I remain firm.  Advances in technology will make the future far richer than it has already!  Compare today to the year 1900.  We are fabulously wealthy by comparison, thanks to technology.  As for God, He has no place on this thread.

Yes, "need" is the keyword.  Will Mars rely on 3He from Saturn or will Mars have an abundance of geothermal energy???  Will there be local martian talent, a Beatles of the future, that rocks the solar system?  A "martian invasion." Certainly, entertainers from Mars would be an export.

New Apollo-Style Capsules Could Replace Shuttles
Wed Sep 17, 6:41 PM ET  Add Science - Reuters to My Yahoo!

By Barbara Johnson

CAPE CANAVERAL, Fla. (Reuters) - NASA (news - web sites) may replace its troubled fleet of space shuttles with a new generation of Apollo-type space capsules, a top space agency official said on Wednesday.

Reuters Photo

"Certainly we have considerable amount of experience flying with capsules," Dr. John Rogacki, director of NASA's space transportation directorate, told Reuters. "One might say on the capsule side it could be that that design experience may lead to a capsule being available sooner than a winged vehicle."

Unlike shuttles that land like airplanes, capsules splash down in the ocean and must be recovered by ships.

The resurrection of space capsules, which last launched three decades ago, is gaining favor among astronauts, space agency officials and congressional staffers after the shuttle Columbia disaster that killed seven astronauts on Feb. 1.

The 13 members of the Columbia Accident Investigation Board were unanimous in urging NASA to replace the aging shuttles as soon as possible by using existing technology and materials.

NASA said on Tuesday that the next space shuttle flight, designed to test repairs that might have saved Columbia, would not make a March launch target and might not fly until midsummer.

The space agency has spent billions of dollars since the mid-1990s trying unsuccessfully to design a new winged spacecraft, begging the question of whether a winged plane could be delivered by 2008 under a now accelerated timetable.

"Boy, I really don't want to speculate on that because I don't want to inadvertently or unintentionally signal to our contractors that I think it is likely or it is not likely," Rogacki said.

15 TO 20 YEARS

Corin Segal, an aerospace scientist at the University of Florida, picked by NASA to design new systems, has estimated that development of the technology to produce a truly safe, winged reusable spacecraft could take 15 to 20 years.

Detailed requirements for what has been called an orbital space plane were issued by NASA this week to three contractor teams who will propose designs and compete for the work.

For now, NASA is careful to avoid publicly expressing any opinion on what shape the new craft should take, and to stress that there are pros and cons to winged and capsule designs.

But NASA spokesman Bob Jacobs said there was no requirement that the craft be plane-like despite its name.

"We haven't spelled out that it has to glide back to Earth and land like a plane. That's not a requirement," Jacobs said.

The capsule design gained momentum in March from a study headed by astronaut John Young, who has flown in both capsules and shuttles. Young, as well as Michael Kostelnick, head of NASA's human space flight program, cite the versatility of the capsule, which can move beyond low Earth orbit to the moon or beyond.

Rogacki said the orbital space plane requirements did not demand the vehicle be capable of deep space travel but that NASA will be looking at its ability to support missions beyond the International Space Station (news - web sites).

"There is a great potential for using the orbital space plane system as a basis for future exploration vehicles," Rogacki said.

The thermal tiles and wing panels used on the shuttle today could not withstand the heat and stress of trans-lunar re-entries.

I get mad at NASA a lot, but is NASA really to blame?  NASA only does what Congress tells it to do.  The aerospace companies pitch things to Congress, but Congress decides, not Boeing or Lock-Mart.  Senators and Reps are not engineers or scientists usually.  Congress changes every so many years and politics rather than good engineering rules.  Why do they ship the SRBs all the way back to Utah for refurbishing?  Why don't they build a refurbishment facility near KSC?  I'll probably be criticized for making accusations with no evidence, but it's probably done to keep jobs in Utah because of some politician.  Sometimes I think the best thing to do is to dissolve NASA entirely and let business figure out what to do, how to do it, and make it cost effective.