If there ever is a time astronauts are reminded why they do what they do, it's when they get to witness stunning sights like this.

According to NASA, crew members of Expedition 43 took this image from the International Space Station (ISS) on May 26, peering at our Blue Planet from nearly 250 miles (400 km) above its surface. It shows the Earth, complete with several cities sparkling in the Sun's light, haloed by a beautiful green aurora. (Want to learn more about auroras and how they occur? Check out these stories.)

And if the beautiful photo isn't impressive enough for you, it's important to remember that the ISS is also orbiting Earth at a stunning 4.76 miles per second (7.66 km/s). That means to be a good cameraman, you're going to need one heck of a shutter speed to get a clear shot.

Thankfully, the ISS has no shortage of adequate photographers and equipment to capture amazing photos like this every day.

NASA astronaut Scott Kelly, for instance, has been tweeting a new photo of the Earth from the ISS once a week since mid-April for his ongoing space-based geography trivia contest.

But Kelly isn't just snapping pictures for fun. He and Russian Federal Space Agency (Roscosmos) cosmonaut Mikhail Kornienko will be spending a whole year in space to help experts better understand the effects that prolonged exposure to microgravity can have on the human body. Sent up to the station last March, Kelly has already been spending a great deal of his time capturing a bottomless photo album of geographic locations for scientific analysis of our planet.

"Expanding our geography knowledge is essential to our economic well-being, our relationships with other nations and the environment," Kelly explained in a statement. "It helps us make sense of our world and allows us to make connections between people and places. Space exploration is a global endeavor, and the International Space Station is the result of these connections."

And if he and his colleagues get to snapshot the occasional jaw-dropper like the above photo as well, then all the better.

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