Page 1 of 2

Anyone fancy a 39-day trip to Mars?

Posted: Fri Jun 04, 2010 9:01 pm
by JazHaz
In the future it may be possible, with development of better electrical generation in space and a very promising plasma engine under development in a private sector lab in Houston.

See: http://www.spaceflightnow.com/news/n1006/01vasimr/

Posted: Fri Jun 04, 2010 10:34 pm
by Kaks
A bit slow, but I wouldn't mind the cruise!

QE2 in space, just what I need when I'm a pensioner! :)

Posted: Sat Jun 05, 2010 4:04 am
by Micha
Is that a flyby mission or stop there? The article wasn't very specific on that.. Sounds like they are making some good progress though.

Posted: Sat Jun 05, 2010 9:06 am
by JensAyton
That’s a stop of a few days, as I recall.

Of course, getting to Mars is easy. It’s getting back that’s the hard part.

Posted: Sat Jun 05, 2010 4:33 pm
by Killer Wolf
why?

Posted: Sat Jun 05, 2010 4:50 pm
by JensAyton
Why which?

Posted: Sat Jun 05, 2010 4:52 pm
by Cmdr James
I guess why is it harder to get back than to get there.

And I guess the answer is that once you escape earth gravity its "easy" to get there, but you have to take enough fuel, oxygen and so on to get back, and the martian gravity is challenging.

Posted: Sat Jun 05, 2010 6:10 pm
by Uncle Reno
Ahruman wrote:
Why which?
Err, they offer impartial advice about products you might buy? :wink:

Sorry, I'll get my coat... :oops:

Posted: Sat Jun 05, 2010 6:30 pm
by Killer Wolf
aye, why the return = harder bit.

Posted: Sat Jun 05, 2010 7:00 pm
by JazHaz
Kaks wrote:
A bit slow, but I wouldn't mind the cruise!
39 days is a bit slow?

With current chemical propulsion it would be a trip of 500+ days!

Posted: Sat Jun 05, 2010 7:21 pm
by JensAyton
Killer Wolf wrote:
aye, why the return = harder bit.
The hardest part of an interplanetary flight is the first couple of hundred kilometres, getting off the planet.

For a return trip from Mars, you need to bring the rocket for that plus the launch facility with you.

This increases the mass of your initial launch by a factor of, say, 50.

Posted: Sat Jun 05, 2010 7:46 pm
by Steve
Ahruman wrote:
Why which?
What?

Posted: Sun Jun 06, 2010 7:13 am
by Killer Wolf
Ahruman wrote:
Killer Wolf wrote:
aye, why the return = harder bit.
The hardest part of an interplanetary flight is the first couple of hundred kilometres, getting off the planet.

For a return trip from Mars, you need to bring the rocket for that plus the launch facility with you.

This increases the mass of your initial launch by a factor of, say, 50.
so it'd make sense to send the equipment on ahead first then, i guess, have it parachuted onto the planet then you could assemble it when you arrived, save carrying it all on your actual ship.

Posted: Sun Jun 06, 2010 9:02 am
by Smivs
Killer Wolf wrote:
Ahruman wrote:
Killer Wolf wrote:
aye, why the return = harder bit.
The hardest part of an interplanetary flight is the first couple of hundred kilometres, getting off the planet.

For a return trip from Mars, you need to bring the rocket for that plus the launch facility with you.

This increases the mass of your initial launch by a factor of, say, 50.
so it'd make sense to send the equipment on ahead first then, i guess, have it parachuted onto the planet then you could assemble it when you arrived, save carrying it all on your actual ship.
The problem here is that you have to land near the equipment drop, and hope it's OK when you get there.
Better to send a second ship, then rendezvouz in orbit. The manned module could then dock with a decent/ascent module (basically a big fuel tank and engine with legs), which could land the manned module and also get it back into orbit at the end of the mission.

Posted: Sun Jun 06, 2010 9:08 am
by JensAyton
Killer Wolf wrote:
so it'd make sense to send the equipment on ahead first then, i guess, have it parachuted onto the planet then you could assemble it when you arrived, save carrying it all on your actual ship.
You still have to launch all of it, in relatively tight launch windows (which come about two years apart).