In efforts to understand how fire behaves in space, NASA set nine material swatches ablaze on the Cygnus cargo ship just before the craft’s dramatic re-entry to Earth.
Now, the space agency has now revealed footage from this experiment, dubbed Saffire-II.
The Cygnus cargo ship operated by the US company Orbital ATK left the ISS, packed with 1.5 tons of garbage, at 8:22 am (1322 GMT) on Monday, and both the craft and its contents will burn up upon entering Earth’s atmosphere.
Scroll down for video
In efforts to understand how fire behaves in space, NASA set nine material swatches ablaze on the Cygnus cargo ship just before the craft’s dramatic re-entry to Earth. Now, the space agency has now revealed footage from this experiment, dubbed Saffire-II
Samples in the experiment kit included a cotton-fiberglass blend, Nomex, and the acrylic glass that’s used for spacecraft windows, according to NASA.
Nomex is a flame-resistant material that’s used for cargo storage bags and as a fire barrier.
After leaving the International Space Station around 8:22 Monday morning, the agency received confirmation at 7:14 p.m. that the first test sample had been ignited.
Within the next hour, Samples 1-6 were aflame, including silicon materials of different thickness, and the same cotton-fiberglass blend used in the Saffire-I experiment.
Of Samples 5 and 6, one was at the same flow speed as the previous test, and the other at the speed planned for the third.
By 9:30 that night, all samples had been burned.
This experiment was the second in a series of three fire safety tests, and launched in October.
Ultimately, the whole spaceship and its contents will burn up on re-entry to Earth’s atmosphere at 6:30 pm (2330 GMT) Sunday.
But until then, the spaceship transforms into a test bed that aims to improve safety for astronauts living in space by helping experts better understand how fire behaves in microgravity.
After leaving the International Space Station around 8:22 Monday morning, the agency received confirmation at 7:14 p.m. that the first test sample had been ignited
By 9:30 that night, all samples had been burned. This experiment was the second in a series of three fire safety tests, and launched in October
‘A spacecraft fire is one of the greatest crew safety concerns for NASA and the international space exploration community,’ said project manager Gary Ruff, part of the team working on the experiment known as the Spacecraft Fire Experiment, or Saffire.
The nine samples of materials set ablaze included ‘flame retardant fabrics used for astronaut clothing, station Plexiglas window samples with edge variations and structures used for storage containers and silicone composites,’ said NASA.
Each sample is two by 11 inches (five by 28 centimeters), and is placed in a separate compartment for the fire study.
‘Saffire seeks to answer two questions,’ said principal investigator David Urban.
HOW FIRE BEHAVES IN SPACE
Footage from the most recent experiment, Saffire-II, is shown
Flames in space burn with a lower temperature, at a lower rate, and with less oxygen than in normal gravity.
This means that materials used to extinguish the fire must be present in higher concentrations.
The slow flow of air from the fans mixing the air in a spacecraft can make the flames burn even faster.
To help understand how flames burn in space, Nasa researchers have previously ignited a small drop of either heptane or methanol.
As this little sphere of fuel burns for about 20 seconds, it is engulfed by a spherically symmetric flame.
The droplet shrinks until either the flame extinguishes or the fuel runs out.
The latest experiment is aiming to test what would happen if flames appear on the ISS on a much larger scale.
The Orbital ATK’s Cygnus cargo craft (L) as seen from the Cupola module windows aboard the International Space Station on October 23, 2016 in a NASA photo obtained October 26, 2016
‘Will an upward spreading flame continue to grow or will microgravity limit the size?
‘Secondly, what fabrics and materials will catch fire and how will they burn?’
NASA said the first fire in the series of experiments would start about five hours after the Cygnus departed.
The goal is ‘to help investigators better understand flammability of these materials in a microgravity environment,’ said a statement by Orbital ATK.
The company said data will be downloaded from the spacecraft via telemetry.
Cygnus launched from Wallops Island, Virginia and arrived at the ISS on October 23, carrying 5,100 pounds (2,300 kilograms) of food, supplies and science experiments for the team of global astronauts living in orbit.