Obama 'deep space' Mars plans in Boeing booster bitchslap Brobdingnagian US aerospace firm Boeing has more or less openly condemned the revised Obama plan for the US space programme, under which no decision on a heavy-lift rocket will be taken until 2015. The space megacorp seems worried at the close relationship between the President and upstart startup rocket firm SpaceX. Elon Musk …
Nothing in space is stationary. For Mars you can use the planet's gravity and atmosphere (yes, it has a little) to pull you into an orbit so you don't have to use engines to stop, and you have more choices for angles so you can go on walkabout and return to Earth without waiting for the Earth to come back into the right orbital position. The asteroids? No. Once you get to the asteroids you have to stop relative to the asteroids using engines because there's no gravity, no atmosphere - and using inertial damping by colliding with asteroids would be traumatic and potentially cause undesired secondary effects. The asteroids are dancing a peculiar dance we still don't understand and it's dangerous territory. As you match orbit to your desired asteroid the Earth spins merrily away, and you'll have to catch it the next time around. It's a minimum 16 month trip barring some innovation in drive technology I haven't heard about.
Not that it matters. For amount of money we're talking about here nobody in the US is going to build anything that leaves the atmosphere. I we're talking about the same level of investment for design costs as the Boeing 787, and that doesn't even reach low Earth orbit. The timescale is too long also. By the time this comes to a workable plan we'll need the permission of Russia, China and India to leave Earth orbit anyway and the Mars landing team will need local work permits and valid passports.
I am not an Obama basher by any means - I really do like the guy and I'm glad he's president. But on this issue he's spinning a story. Today he's taking the trouble to tell it well because when he drew a big red X on NASA's budget he discovered that manned space exploration has a constituency too. Somewhere in there I'm sure the NSA briefed him on the value of the USA space engineering team, and how if they can't pursue manned US spaceflight like they want to, they might be persuaded to help Pakistan with their cruise missile problem.
Go or don't go. Don't waste billions of taxpayer dollars pretending to try. If we're just going to pretend, give the budget to James Cameron and ask him to generate some good simulated visuals. If we're going to pretend, then let's pretend WELL. Don't pretend the next time the parties switch power - and they always do - that this long term plan won't again be devalued and scrapped in favor of "a new vision that will work this time - we promise!"
Ask Bruce Willis. Bit of cgi here, flag waving there, bob's your uncle.
Same thing with mars. They could probably get some decent footage from "Mission to Mars" or "Red Planet"
I don't know why Obama doesn't want to do the Moon again. After all, looking at hollywood sometimes, you'd think that remakes were all the rage...
Whatever it is, the thing here to have is lots of flag waving.
Which did you like more? Armageddon or Deep Impact. I'm convinced Bruce Willis saved the world and therefore owns Chuck Norris and Vin Diesel put together.
See?
Neither U.S. nor anybody else will make a manned Mars visit, until the silly taboo against using nuclear power in space (real reactors, not weak RTG:s as on many probes) is broken.
For this reason, I'm betting on China or Russia getting there first, as their space agencies aren't as hindered by public opinion...
"1) VASIMR runs off of electromagnetics and plasma, not nukes (though it could use nuclear power to run it all, I suppose)."
I think you'll find that like various other charged particle drive systems it runs off *electricity*. It's *not* a fusion drive by a *long* stretch of the imagination. Nuclear, solar and beamed microwave could all supply the power.
"2) What you're looking for is likely NERVA, and most recently Prometheus (begun in 2003)."
Nuclear thermal (note 2 separate words in that order) of which NERVA was one design have *very* poor thrust weight ratios by rocket engine standards (c1.1 to 1. Isp in the 7-900 range. A good conventional lox/kerosene engine can get 100:1. Nuclear engines are still a way from a flight weight design, while their Isp is better (but not much more than twice) that of a LOX/LH2 engine. Ion and plasma drives hit Isp's of 2000s and above. Some are promising 20 000s.
Nuclear thermal is starting to look like a bit of a dead end. Its Isp is better than chemical systems (but not *that* much better. BTW the record for chemical Isp is about 576s, using the insanely dangerous fluorine/sodium/hydrogen tri-propellant). "Energetic materials" like monotomic hydrogen are promising energy levels in this ball park as well. The materials and maintenance problems for nuclear thermal are still formidable (The temperature ranges, -253-+2000c are the same as chemical rockets but the heating mostly takes place by conduction between the -253c H2 and the c2000c reactor coolant channels. Can you say thermal stress?)
"Neither U.S. nor anybody else will make a manned Mars visit, until the silly taboo against using nuclear power in space (real reactors, not weak RTG:s as on many probes) is broken."
Nuclear is *the* elephant in the room. It opens up a *lot* of options in terms of engines (mostly as an electricity supply rather than as a direct drive NERVA type unit) and surface support. It's not just the power levels than can provide, its the life expectancy.
Without it mission planning is tricky. solar thermal and PV might work on the moon, but what about the 2 week nights? Mars sunlight is less than 1/4 that on Earth. Martian windmills maybe?
so whose going to be the elephant man?
Executive has their secretary help write a scathing rebuke. They try to invoke a sense of national pride and generally make it seem like its a huge loss for the American people. But in reality boeing is pissed because a president isn't playing their version of ball. How long before you see "lobbyists" whispering in senator ears about how terrible this is for american goals.
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