One of my new favorite sites is Fragile Oasis, a blog where astronauts write about their experiences in space and on Earth. Don Petit, an American who has taken so many of the amazing pictures that have graced not just this blog but have gone viral across the web, posted a nice description of taking star trail pictures on orbit. This one in particular is surpassingly beautiful:
You can see part of the International Space Station at the top (I think that's the lab section, with the node Destiny and the JEM facility, but I may be mistaken). The stars are blurred from motion, with the thickening on the right of the Milky Way, the combined light of billions of stars.
The slight motion blurring makes it look like the ISS is moving at warp speed over the planet. The Earth's atmosphere is the thin green/brown haze over the Earth's limb, with the top sharply defined by the aerosol layer. The red glow is interesting. That may be an aurora, but it might also be an internal reflection; Don shot this through the cupola window. Reflections plague the shots sometimes... but my gut tells me this is auroral in nature.
Either way, this is a stunning shot, and I found Don's description really interesting. What an opportunity, to see the Earth from above all the time, and to be able to place it so well among the stars where, honestly, it rightfully belongs.
Image credit: NASA