Spacecraft fires are one of the most dangerous situations an astronaut can face. With Saffire, NASA hopes to better understand them.
Image: NASA/Wikimedia Commons
Astronauts face a wide range of existential threats as part of their profession, but few are more perilous than the possibility of a fire breaking out on a spacecraft. With that in mind, it might sound a little strange to hear that NASA will be literally playing with fire in space this week, as part of the agency's ongoing Spacecraft Fire Experiment (Saffire) mission.
Saffire experiment explainer. Video: NASA Glenn Research Center/YouTube
Before you start tweeting warnings to the current International Space Station (ISS) staff, rest assured that the Saffire experiments will be conducted onboard on the unmanned Cygnus cargo capsule, which disembarked from the station on Monday morning at 8:22 AM EST. No humans (or animals) will be harmed in the making of these tests!
The Cygnus ship, manufactured by private spaceflight company Orbital ATK, originally arrived at the ISS on October 23 and successfully delivered 2,400 kilograms (5,290 pounds) of food, supplies, and science equipment to the crew.
Unlike the reusable SpaceX Dragon capsules that also ferry goods to the ISS, Cygnus is an expendable capsule destined to burn up in the atmosphere. This disposability makes it a low-risk platform for NASA to channel its inner pyro without worrying about payload damage, because the capsule will be reduced to atmospheric ash on Sunday anyway.
READ MORE: How to Put Out a Fire in Space
Beginning this Monday afternoon, the Saffire team will begin igniting nine materials in the Cygnus using a hot wire. The results will be recorded by sensors and a camera, and the data will be relayed back to Earth via telemetry.
Each sample measures two by 11 inches in size; the materials include astronaut clothing fabric, ISS window Plexiglass, silicone composites, and parts of storage containers. The goal is to assess the relative flammability of common ISS materials, which is valuable information in terms of preparing for these emergencies in the future, especially on long-duration missions such as crewed voyages to Mars.
First Saffire experiment conducted in June 2016. Video: NASA/YouTube
The experiment is the second phase of a three-part mission arc that began in June 2016, when NASA burned up fabricmade from fiberglass and cotton on a previous Cygnus resupply trip. A third experiment is expected to take place in March 2017.
Given that dangerous fires have already ravaged inhabited spacecraft—most notoriously on the Mir space station in 1997—insights into fire's behavior off-Earth will be an essential part of ensuring astronaut safety as humans venture further from our planetary homestead.
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