NASA just started the biggest fire in outer space ever intentionally set—all in the name of safety, Space.com reports. The Spacecraft Fire Experiment, aka Saffire-1, took place Tuesday inside an unmanned Cygnus cargo vessel after it left the International Space Station, with what a press release describes as a 16-inch-by-37-inch cotton-fiberglass cloth remotely set ablaze so scientists could then measure how the fire outside of Earth's atmosphere affected oxygen use in the craft, how quickly the flame grew, and other factors so that future missions could be made safer. "Our #Saffire experiment traveled 1,000 miles in space while burning on #Cygnus," NASA's Glenn Research Center tweeted Tuesday, adding it would start releasing images from the fire, said to be capable of reaching temps as high as 1,500 degrees Fahrenheit, this week as they're beamed back to ground controllers. The largest intentional fire sparked before this was the size of an index card—providing valuable info, but not enough to truly see the consequences of a real in-space blaze.
"To really understand fire, you've gotta look at a more realistic size," a Saffire-1 investigator said during a March press call, Gizmodo reported then. "One of the big questions in fire safety ... is how rapidly are conditions in a ... spacecraft going to get bad for inhabitants." It was a challenge to even start these experiments, as most engineers were unwilling to risk trashing the spacecraft they had worked so long on, the Washington Post notes. "We tried for years, trying to find a vehicle and a circumstance where this would work," the lead Saffire investigator said in a video posted June 6 on YouTube. "Initially they'd get a 'not on my spacecraft' reaction." The Cygnus cargo vessel compromise was eventually reached, and Gizmodo notes NASA made sure to start the fire far away from the ISS, so already anxious-astronauts hanging out there wouldn't get freaked out seeing the fire so close to their perilous perch. Two more space-fire flights—Saffire-2 and Saffire-3—are planned for later this year. (In other NASA news: a scientist who says he can get humans to Mars in a month.)