Bad Astronomy

MESSENGER moves off

In my last blog entry, I talked about how the Mercury probe MESSENGER took images of the Earth as it flew past our home planet a year after launch. In that entry, the focus was on the different filters the probe used.

But I only showed two images. In fact, MESSENGER took hundreds of images during that flyby, which means they can be strung together to get an animation. And that’s just what scientists did. The animation they made is phenomenal: it shows the Earth from a distance of just 66,000 kilometers– not much farther out than weather satellites orbit– and then continues as MESSENGER zipped past us, out to a distance of 436,000 kilometers – farther than the Moon – over the course of about 24 hours. Mind you, it took more than three days for the Apollo astronauts to get to the Moon, so MESSENGER is really hauling. During the movie, you can see the Earth rotating all the way around once.

So much for geocentrism.

Anyway, the movie is pretty big, more than 4 Mb, but it’s well worth the wait. The sense of being there on board the little spaceship is palpable. The images are really clear and clean, and there is something very special about seeing our blue marble against the velvet of deep space.

And oh, by the way: Dean was right. Ironically, this was sitting in my “post about it” pile for a long time, too.’