It was my third cleanroom visit, my second to see an actual spacecraft, and my first at a launch facility. I have been inside clean rooms at JPL twice, once to see Curiosity and another to see the LDSD test vehicle.

This visit was very, very different from the one where I got to see Curiosity. The spacecraft was fully assembled but not undergoing final preparations. The mood was anticipatory but relatively relaxed. We had stacks of time to wander around the wide-open space of the JPL High Bay (within limits imposed by stanchions), take lots of video, do interviews, record our own video, take lots of photos.

Things were very different at Vandenberg. We were dealing with a fully fueled spacecraft just weeks away from launch. Any mistake, no matter how tiny, could jeopardize the launch. We were prepped at length on the importance of planetary protection. Media were robed up, ushered in to the room only in groups of three and evacuated before the next group allowed in. That gave us just minutes inside. Merc and I got about three minutes to interview Bruce Banerdt, another two with a senior manager and an engineer, and then were told we had to go. It was all a bit of a rush, so I didn't get time to sit and reflect with the spacecraft that was really going to Mars. But I got a few pictures, and will reflect now!

For the scientists, it'll be a very long wait until landing. Everything is pretty much in the engineers' hands until then. Banerdt told me he's only been in the clean room with his spacecraft maybe four times, total. He was happy and excited to be so close to launch, finally.