scott kellyNASA

From 250 miles up, astronauts have an unparalleled view of Earth. They can also easily see the devastating effects of climate change and pollution as they ravage the planet.

That's why past and present astronauts from around the world have contributed to a new video, called "Call to Earth," that urges world leaders to take action.

It's an inspiring collection of pleas, but also a sobering and gut-wrenching one: If we don't clean up our act as a species, and fast, we could irreversibly mar the only home that we've got in the solar system.

Here are the some of the most salient quotes from the video.

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