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NASA Wants Spacecraft For Mars Return Trip
coondoggie writes "If we ever do get to Mars, getting home might prove to be as difficult. NASA today selected three companies — Alliant Techsystems, Lockheed Martin and Northrop Grumman — to being the task of defining the spacecraft that will leave Mars, presumably at first loaded with red planet rock samples, then later possibly humans — for a safe trip back to Earth. The engineering challenges those three companies face are immense."
We don't pay for any bids that specify the same ship design be used for the return as was used during the departure.
I'd design it so it had just enough thrust to get back in Mars Orbit. Then I'd send a 2nd craft from Earth to ferry it back. I figure there is a lot of problems that could be solved by reducing that added fuel weight from it.
God spoke to me.
Who needs to come back. We should send a one way craft, there would be countless volunteers even if it was clear that they are never coming home. Once there, you could start working to establish a sustainable off planet colony... Would also make getting there a lot cheaper.
"There does not seem to be sufficient short-term profit to motivate private industry. If we humans ever go to these worlds, then, it will be because a nation or a consortium of them believes it to be to its advantage" -Sagan
Carl Sagan quotes get you an automatic +5 on all posts.
"The engineering challenges those three companies face are immense"
The bureaucratic challenges will be even more so.
http://www.rootstrikers.org/
These big contractors will never come up with an efficient solution. It is against their interests. They will design some very capital intensive approach. Then they will bid on the contracts to build it.
It will take a startup company to come up with a innovative and viable approach.
...Robert Zubrin 1996 http://en.wikipedia.org/wiki/The_Case_for_Mars for a decent affordable, credible, realistic and possible plan.
Then, if anyone reading this knows Elon Musk, please send him a copy.
Huh?
We have ways to get to Mars just fine. An Atlas V 541 is enough to get the massive MSL Curiosity Rover there, and a measly Atlas V 401 is plenty for the Maven orbiter coming after that.
The hard part is getting back. I imagine grabbing resources from the surface and air to create rocket fuel while performing its mission will be the right way to go.
A Mars Sample Return is where the Mars program is headed, and we have a roadmap to get there. And it will force the development of In-Situ Resource Development (ISRU), while will be of huge benefit to all future manned and unmanned programs.
...all the tens of thousands of people that would be employed to make this happen... I guess none of they money spent by them would go back into the country? They would spend it all offshore right? Riiiiiight...
Before they start working on how to get OFF of Mars they need to figure out how to get ON Mars. A couple of years ago I found this article (sorry, lost the original link).
Getting Large Payloads to the Surface of Mars
by Nancy Atkinson
July 17th, 2007
Some proponents of human missions to Mars say we have the technology today to send people to the Red Planet. But do we? Rob Manning of the Jet Propulsion Laboratory discusses the intricacies of entry, descent and landing and what needs to be done to make humans on Mars a reality.
There’s no comfort in the statistics for missions to Mars. To date over 60% of the missions have failed. Even among those who have devoted their careers to the task, mention sending a human mission to land on the Red Planet, with payloads several factors larger than an unmanned spacecraft, and the trepidation grows even larger.
Why? Nobody knows how to do it.
Surprised? Most people are, says Rob Manning the Chief Engineer for the Mars Exploration Directorate and presently the only person who has led teams to land three robotic spacecraft successfully on the surface of Mars. "It turns out that most people aren’t aware of this problem and very few have worried about the details of how you get something very heavy safely to the surface of Mars," said Manning.
He believes many people immediately come to the conclusion that landing humans on Mars should be easy. After all, humans have landed successfully on the Moon and we can land our human-carrying vehicles from space to Earth. And since Mars falls between the Earth and the Moon in size and atmosphere, it should be easy. "There’s the mindset that we should just be able to connect the dots in between," said Manning.
The real problem is the combination of Mars’ atmosphere and the size of spacecraft needed for human missions. While the Apollo lunar lander weighed approximately 10 metric tons, a human mission to Mars will require three to six times that mass, given the restraints of staying on the planet for a year. Landing a payload that heavy on Mars is currently impossible, using our existing capabilities. "It’s this ugly, grey zone", said Manning, "There’s too much atmosphere on Mars to land heavy vehicles like we do on the moon, using propulsive technology and there’s too little atmosphere to land like we do on Earth. Until we come up with a whole new system, landing humans on Mars will be an ugly and scary proposition."
In 2004 NASA organized a Road Mapping session to discuss the current capabilities and future problems of landing humans on Mars. Manning co-chaired this event and the major conclusion that came from the session was that no one has yet figured out how to safely get large masses from speeds of entry and orbit down to the surface of Mars.
"We call it the Supersonic Transition Problem," said Manning. With our current capabilities, a large, heavy vehicle, streaking through Mars’ thin atmosphere only has about ninety seconds to slow from Mach 5 to under Mach 1, re-orient itself from a being a spacecraft to a lander, deploy parachutes to slow down further, then use thrusters to translate to the landing site and finally, gently touch down.
When this problem is first presented to people, the most offered solution, Manning says, is to use airbags, since they have been so successful for the missions that he has been involved with; the Pathfinder rover, Sojourner and the two Mars Exploration Rovers (MER), Spirit and Opportunity.
But engineers feel they have reached the capacity of airbags with MER. "It's not just the mass or the volume of the airbags, or the size of the airbags themselves, but it's the mass of the beast inside the airbags," Manning said. "This is about as big as we can take that particular design."
In addition, an airbag landing subjects the payload to forces between 10-20 G’s. While robots can withstand such force, humans can’t. This doesn’t mean airbags will never be
I'm surprised that nobody has yet mentioned nuclear-powered spacecraft, which propels itself with an ion thruster: http://en.wikipedia.org/wiki/Ion_thruster Such a spacecraft would not have a problem carrying enough fuel to make the return trip. I do need to point out that that space vehicle would not lift off from earth using its nuclear-ion thruster, nor would it land on Mars. It would have to first be propelled into earth orbit with conventional hydrogen-oxygen rockets. The nuke engine would then "go live" propelling it to Mars, where it would stay in orbit. It would drop a module down to Mars (which uses parachutes and the "beachball" technique to land safely). After collecting samples, it would lift off Mars using a conventional rocket and rendezvous with the nuclear-powered craft in orbit, which would return to earth (but stay in orbit). Conventional rockets would be used to recover the payload and take it back to earth. Think of this nuclear-powered rocket like a kind of miniaturized Starship Enterprise, though unmanned. It doesn't land or take off from a planet, it just ferries payloads between planets, never getting any closer than an orbit.