Right now, NASA TV is offering the chance to see something pretty cool: live footage of a spacewalk by astronauts on the International Space Station.
Broadcast live streaming video on Ustream
The video is of a pair of Russian cosmonauts, Alexander Skvortsov and Oleg Artemyev, who headed outside at about 10 am Eastern time this morning to deploy a small satellite that will take photos of Earth. They'll spend about six hours in total outside the craft, as they're also installing a few pieces of equipment on its surface.
The walk is being filmed by cameras built in to their helmets (when the display shows 18 in the bottom-righ corner, that's Skvortsov’s helmet camera, and when it shows 17, that's Artemyev’s).
In total, this is the 181st space walk conducted outside the International Space Station.
Update: The spacewalk is over, and the feed above now shows other programming on NASA TV.