Alien asteroid

Interesting astronomy news:

Astronomers have spotted some kind of outer space rock that's the first visitor from outside of our solar system that they've ever observed.

The discovery has set off a mad scramble to point telescopes at this fast-moving object to try to learn as much as possible before it zips out of sight.

"Now we finally have a sample of something from another solar system, and I think that's really neat, " says Karen Meech, an astronomer at the University of Hawaii Institute for Astronomy, "and so you'd love to see if it looks like stuff in our solar system."

It's long been assumed that an interstellar object like this one should be out there, because giant planets in forming solar systems are thought to toss out bits of space crud that haven't yet glommed into anything. But this is the first time scientists have actually found one.

The mysterious object is small — less than a quarter mile in diameter — and seems to have come from the general direction of the constellation Lyra, moving through interstellar space at 15.8 miles per second, or 56,880 miles per hour.

But there's no tension in this - it was spotted on the way out of the solar system, not on the way in (when we could all have speculated as to whether it was actually an alien spaceship):

"The orbit is very convincing. It is going so fast that it clearly came from outside the solar system," says Paul Chodas, manager of NASA's Center for Near-Earth Object Studies at the Jet Propulsion Laboratory in Pasadena, Calif. "It's whipping around the Sun, it has already gone around the Sun, and it has actually gone past the Earth on its way out."