Stargazing takes on a whole new meaning when it's done from the International Space Station.
NASA astronaut Don Pettit took some amazing long-exposure photos of star trails. You get a strong sense of the Earth's rotation as the vivid images shift.
"Space Station makes one revolution every 90 minutes (the Moon takes 28 days)," Pettit wrote in a blog post . "As a result, long-exposure pictures taken from the station show star trails as circular arcs, with the center of rotation being the poles of Space Station."
"Due to our altitude, it is possible to see both the north and south axis of our orbit at the same time. This makes possible star trail images with two circles defined by arcs with opposite inflections. This geometry is hard to arrange from only one window so I use a fisheye lens, one with a full 180-degree image circle, to make this composition."
Pettit also wrote that he used a time exposure of about 10 to 15 minutes to capture the star trails. Because modern digital cameras allow only about 30 seconds of exposure possible, Pettit said he took multiple 30-second exposures. He then stacked them using imaging software, which produced the longer exposure.
"Normally, these star trails are created as the Earth rotates on its axis, with the center being close to either Polaris, the north star, or the Southern Cross, depending on which hemisphere you are in," he wrote.
The photos also capture some amazing natural phenomena such as auroras above the Earth.
Pettit is currently on a 30-day mission aboard the space station.