Spirit has climbed to the hilltop and looked over the other side, but NASA did not do this just to say we can do it. The Mars rovers are addressing fundamental questions about Martian history and planetary environments.

Spirit and Opportunity are approaching targets that a year ago seemed well out of reach. Their successes strengthen NASA's commitment to a vision with the ambitious targets of returning samples from Mars and sending human explorers to Mars.

It's a little nerve-racking even though it's exciting.

First we have to get it into orbit, which is not an easy task.

It's going to be difficult to get it into orbit. Mars is hard, Mars can be unpredictable, but we've got a good team here.

This is a little bit nerve-wracking, although it's exciting.