It was first discovered in 2004 by a team of astronomers working at the Kitt Peak National Observatory in Arizona, United States.
They only managed to observe it for two days, however, due to technical problems and poor weather conditions. The faraway visitor remained lost to astronomers until another group at the Siding Spring Observatory, Australia, caught a glimpse of it.
This time they were able to piece together its trajectory.
How do they know that these two were the same lump of rock, given they couldn't work out it's trajectory until they saw it the second time?
(We really need a "?" icon for when you're actually asking a question.)
Biting the hand that feeds IT
