Slashdot Mirror
Hayabusa Probe Lands on Asteroid After All
pin_gween writes "Reuters.UK is reporting the the Hayabusa space probe successfully landed on the asteroid Itokawa. JAXA officials are trying to determine whether to attempt another landing. The probe has had a series of glitches, and failed to drop a set of instruments upon landing."
...apparently did not deploy its sampling tools, which was kind of the point of the mission. Still, it's a pretty major feat and the article says they might try again, to see if they can get their samples. And check out this great image of the asteroid with the probe's shadow.
GetOuttaMySpace - The Anti-Social Network
Look, a TIE-fighter shadow! (which as everyone knows, is a short-range fighter.)
One line blog. I hear that they're called Twitters now.
No, not really... because in order to get to the asteroid, you've got to match orbits with it, which means that you're already going to whereever the asteroid is going.
Wouldn't they provide rudmentary protection against space radaition somewhat?
This might be more useful, but given that the only major cause of radiation in space is the sun, and shielding machines against solar radiation isn't actually that hard, it's probably not worth it.
If you ask me, NASA and other space agencies should be firing out probes like crazy.
Absolutely.
Given that we now have two designs of Mars probe that have proven to be wildly successful --- the Spirit and Opportunity rovers, and the Pathfinder lander --- I think that the right think to do now is to mass produce them, bulk launch them, and drop a dozen of each on Mars. Because the design's been finalised, the cost per probe should be a fraction of what it was for the original; just work from the blueprints. And because you're launching lots, you can stand a higher failure rate, so you can target more interesting parts of the planet. That way you should be able to get some seriously interesting science, very cheaply.
(The reason why all the Mars probes are showing really boring bits of desert is because they've been deliberately targeted at wide, flat areas to increase the chances that they'll get down safely.)
Over a distance of 3x10^11 m they land on an object only 548 m long. The corresponding opening angle is so small that my calculator cannot do the math.
Congratulations!
The first successful asteroid landing attempt was done on Eros by the NEAR spacecraft :
See Here.
The amazing thing is that NEAR was not even designed to land : they mission controllers did it because NEAR was running out of fuel and would be turned off anyway so they decided to chance it. They put it down (after a few bounces on the surface too) and turned it off. One day they might try to turn it on again.
The point is, that it is not impossible to do it. Indeed, the physics is pretty simple. There is no "hitting a fast moving target" problem : the probe is already in orbit and moving pretty slowly relative to the asteroid. The problem is systems engineering : all the problems that you see from the probe is not because some tools malfunctioned outright etc, it is poor integration of systems. Just look at the communications downlink blackout during the landing rehearsal that results in the loss of the MINERVA miniprobe. I mean, come on, you can PREDICT when those blackouts occur!
Finally, your rant about "Japanese cheating to save face" is just pure flamebait.
Mode (3) smart-aleck mode. Press * to return to main menu.
To land on an asteroid you have to speed up your space probe to a speed that's within a few FPS (Feet Per Second) of your target asteroid, as well as get your probe going in the same direction. Can't meet your 1000 MPH asteroid while you travel at 100 MPH. That's like hitting a wall at 900 MPH.
Now that's not so hard to do that we'd never consider doing it (in fact we[humans] have done it.)
Here's the catch. Once your spacecraft/probe is flying at the same speed and in the same direction as the rock you want to ride on, why bother with the landing? Rocks go through space on and on because they are in an orbit, and will follow that orbit till pushed out of orbit (gravity, impact, thrust from a drive.) Your spacecraft/probe will also stay in the same orbit until it is pushed out of that orbit.
So, now that we have some super-simplified physics we can get to the point.
If you're going to burn a certain amount fuel to put your craft into a certain orbit it'll stay in that orbit. It dosen't make a diffrence if it's sharing that orbit with a rock or going solo. Trying to set up an elaborate ballet between your probe and another body is a risk that's not needed (unless your goal is to study those bodies found in space.)
As far as protection from radiation goes, spacecraft have spent decades (Voyager craft) in space with radiation shielding integrated into them certainly seems like enough that we don't need to use asteroids (of unknown composition) for radiation shielding.
As far as the use of landing on asteroids, there's a whole hell of a lot that we don't know about them. It is worthwhile to make these landings for the sake of learning about our solar system. (Not looking for a debate on funding for space science vs spending elsewhere.)
Blessed are the pessimists, for they have made backups. -- 0 1 My two bits
It's a robot. A space robot. A Japanese space robot. You know what those things are like.
It's probably going to head off to another planet to fight giant fearsome monsters now.
Real Daleks don't climb stairs - they level the building.