NASA Schedules Robotic Spacecraft Launch

Nathan writes "NASA has finally set the launch date for their first robotic spacecraft, intended to "rendezvous in orbit with other satellites without any human intervention", to the 15th of April. The spacecraft, called "DART" as an acronym for "Demonstration of Autonomous Rendezvous", cost $110 million dollars and weighs 800 pounds."

Comments

Hubble

[b0lt]

Is there any way to use it to (attempt to) fix Hubble? There's not all that much risk, it would keep Hubble operational, and it would test robotic technology. Is the robot functional enough to carry out repairs?

-b0lt

In the news...

[quarkscat]

Gee, why is this so significant?
Well, try tying a few news articles together.

(a) Bush revives the Star Wars program
(b) Bush cuts NASA spending (HST)
(c) NASA invests in robotic satellites
(d) Bush appoints Star Wars exec to head NASA
(e) NASA announces first robotic satellite

Anyone that cannot add these up and come up
with the correct answer -- the USA is fully
engaged in the militarization of space, is one
can short of a six-pack.

Dumb mission

[QuantumG]

Wow, isn't $110 million a lot for that? I mean, say you were a commercial concern and you wanted to do something that was actually profitable in space. You could send a robot probe to one of those asteroids that circle the sun in orbits close to earth and mine it. At least a few of those asteroids have high quantities of platinum. Say your robot probe could mine a tonne of it and return it to earth. How much would that be worth? Oh, about $30 million. So how many tonnes would your robot probe have to return to earth to be profitable? It's a finite number and wouldn't even make up a significant fraction of the total mass of the asteroid. Sounds like a pretty simple project really. If you could send back enough loads you could afford to sent humans instead of robots and cut out all that pesky upfront R&D. Just grab yourself 5 SpaceX boosters, point and shoot.

Oh well, I suppose China/India/Japan or commercial interests will get around to it sooner or later.

Re:I'm not sure why this is so significant

[WhiplashII]

A lot of good points, but "dropping rocks" from orbit is a lot harder than it looks. Small rocks wouldn't survive reentry, and large rocks are too hard to move to an impact trajectory. Remember, in order to alter the orbit of an object large enough to do damage in order to miss the Earth we would need years and notice and use of our most powerful energy sources. Unless we find a rock almost about to hit Earth anyway, it would be nearly impossible to do damage using rocks.

This is a common enough thought that perhaps there is a misunderstanding of orbital mechanics? If you are on the space station, and throw a rock down, it will go down for half an orbit, then come back up and smack you (or if it misses it will go about as far up away from you as it went down). In order to have the rock hit Earth, you need to throw the rock hard enough to go into the atmosphere and not bounce back out. If you throw it directly behind you, you have to throw it 200-400 m/s or so. But then it reenters like any other meteorite - unpredictable impact zone and unlikely to survive atmospheric heating. To really cause damage, you would need to give it 2000-4000 m/s (about half orbital speed) so that it goes almost straight down. Of course, that takes so much energy that you might as well just use an ICBM.

The danger from space would be beamed weapons. My favorite would be a high-intensity millimeter wave transmitter - it would cause intense, nonlethal, but dibilitating pain in the target. That way you can incapacitate all the bad guys, send in the good guys, and noone has to die. (Well, before the trial at least...)