Floating hundreds of miles above Earth, astronauts have an unparalleled and beautiful view of the planet.
But that view also lets them look down on the devastating effects of climate change, wildfires, war, pollution, and other troubling human-caused activity.
That's why astronauts from around (and above) the world contributed to a 2015 video titled "Call to Earth," which urged world leaders to take action ahead of the Paris Agreement.
The collection of pleas is not only inspiring, but also sobering: If we don't clean up our act, and fast, we could irreversibly destroy the only home we've got.
Here are the some of the most salient quotes from the video.