This is a picture of the nucleus of a comet known as Wild 2.
The picture was taken by a spacecraft that we sent out to take pictures of it–AND retrieve samples of its tail.
That mission–known as Stardust–passed through Wild 2′s tail and collected samples of the particles that were blowing off the comet.
Now those samples are scheduled to be returned to Earth, when Stardust is supposed to drop its sample capsules in Utah.
I always get nervous whenever NASA tries to get samples of extraterrestrial materials down to Earth.
They’ve already established that there are loads of organic molecules in space, and we have reason to think that there may be extremeophile bacteria–including some here on Earth–that could withstand conditions in space.
Of course, tons (literally!) of space dust falls on Earth every day, but our atmosphere provides a protective shield in that a lot gets burned up and sanitized before it makes its way down here.
But that doesn’t happen if NASA puts space dust and rocks in a nice, protective capsule to shield them in the re-entry process.
I know that the odds of anything harmful getting out may be low, but still . . . it makes me nervous.
If you hear of any mysterious diseases suddenly starting in the Utah area next week, start praying really hard.
In the meantime,
P.S. If you’ve never thought through the associated problems here, try renting and watching The Andromeda Strain in anticipation of the event.
