In 2011, the NASA space mission Dawn will enter orbit around the second largest asteroid: Vesta. This rock is about 530 km (320 miles) across, and is just barely big enough for its own gravity to crush itself into a sphere. Well, almost. It's not quite spherical, but it's close. Since it never gets closer than about 200 million km (120 million miles), we don't have clear pictures of it. But we need to get data before Dawn enters orbit, so that surprises are kept to a minimum. That's why Hubble was pointed at Vesta in February, returning some of the best images yet:
I know, they're still fuzzy, but c'mon! You're looking at something roughly the size of my home state of Colorado from more than 200 million kilometers away! And there's stuff to see. Vesta rotates once every 5.34 hours, and the numbers under each picture represent the ...
