At first glance, lighting a fire on the International Space Station (ISS) seems like a good way to earn a Darwin Award and the opprobrium of all humanity. Yet boffins have been doing it for some time in an effort to learn more about how flames behave.

Interestingly, is the answer from NASA, which today offered a look at some ISS fire experiments that have found fires lit in microgravity don't form the familiar forked tongues we see on earth, but instead dimly-glowing spheres that aren't nearly as hot to the touch as earthly flames.

These cool fires can also burn fuel without producing visible flames. The chemical reactions involved are “completely different,” Dr Forman A Williams, a professor of physics at UC San Diego and one of the boffins involved in the FLEX experiment that studies flames on the ISS, told NASA. “Normal flames produce soot, CO2 and water. Cool flames produce carbon monoxide and formaldehyde."

It's possible to figure this stuff out because, the FLEX project says “In the absence of gravity, small droplets of fuel burn 'one-dimensionally', which … allows the science team to easily measure and understand important features of the burning fuel that would otherwise be impossible to obtain on the ground.”

“This particular type of flame configuration allows measurement and observation of very complex interactions in a spherically one-dimensional system, providing insights into the behavior of combustion phenomena that would otherwise be difficult, if not impossible, to obtain in multi-dimensional systems that are typically found in most 1-g fires.”

The results described above have boffins excited that if we make terrestrial fires behave like fires in space, it could make for more efficient internal combustion engines. Gaining knowledge to improve spacecraft safety is another hoped-for outcome.

The rather saccharine video below offers more detail on the experiment and includes footage of the flames.

Watch Video

The FLEX project will continue into 2014, with experiments to trial different fuel mixes planned. ®