Hayabusa To Begin Long Journey Back to Earth
Sparky writes "Japan is planning to set the Hayabusa spacecraft on a trajectory back to Earth next month after a delay of more than a year, but it's far from certain that it will get back safely. It was supposed to retrieve asteroid debris, but it's thought that a computer error prevented that from happening. A fuel leak means that its chemical thrusters are out of action, and the craft is relying on its weaker ion engines. The journey back will take 3 years, and the capsule will be on Earth in June 2010 — even if it is empty."
Basically, the technology to retrieve a satellite from where it is now is likely just as hard as the original mission. Additionally, by the time retrieval would be possible, what would be the point? Technology marches ever on; even if they could retrieve Hayabusa, it's old technology now.
:)
Additionally, such probes are one-shot devices. The components are built to specs to survive hard solar radiation, exposure to space, and all the extreme temperatures involved. I'd venture to guess they'd have to basically rebuild the satellite almost completely to be able to make another attempt with it. It's cheaper to just start from scratch and include the advances available to you.
Now, why bother trying to get it home? It's by no means as important as Apollo 13 (in that no lives are depending on it), but to take a probe that's seen better days and get it all the way back home in the face of what appear to be nearly insurmountable odds has quite a bit of sentimental value. For Japan to get Hayabusa home even in such a depleted state, it would be a great honor to their scientists. (And the fact that there's still *some* chance, albeit very small, that there may have been some material captured just makes it that much better.)
It's the "Incredible Journey" of satellites, or perhaps more apropos, it's the wounded samurai doing everything he can to make it back home before he dies. Very Japanese, and quite a good potential story, too.