Researchers in Germany are melting chunks of satellites in high-temperature plasma wind tunnels to simulate how space debris burns up in Earth’s atmosphere. These tests are revealing in relation to trends about satellite reentry as the population of objects in low Earth orbit swells today . Only a handful of facilities around the world are capable of conducting reentry simulation tests like the German researchers are performing. In particular, the researchers raise concern that ashes from reentry that remain in the upper atmosphere could increase ozone depletion and alter the atmosphere’s thermal balance in the process. Three or more large satellites or used rocket stages burn up in Earth’s atmosphere every day, according to the European Space Agency’s Space Environment Report published last year . Every year, hundreds of tons of human-made objects reenter the atmosphere and evaporate, leaving behind clouds of microscopic ash along with some fragments that happen to fall all the way to the ground.…