Fire Burns Differently in Space, Space Station Experiment Shows | NASA & International Space Station Science | Fire & Microgravity Research | Space.com

Fire Burns Differently in Space, Space Station Experiment Shows: To study fires in space, FLEX researchers ignite a small drop of heptane or methanol fuel in a special experiment rack aboard the space station. As the droplet burns, a spherical flame engulfs it, and cameras record the whole process.

So far, researchers have observed some unexpected phenomena.

"Thus far, the most surprising thing we've observed is continued apparent burning of heptane droplets after flame extinction under certain conditions," Williams said. "Currently, this is entirely unexplained."

Short Sharp Science: 'Liquid fire' created by fluids in a tight spot

Short Sharp Science: 'Liquid fire' created by fluids in a tight spot: Normally, fluids do not mix well in tight spaces because there is not enough room for disorder. But if the fluids exhibit highly contrasting viscosities, such as those of molasses and water, the researchers discovered that finger-like appendages known as viscous fingers project out of the thinner liquid (the lighter fluid pictured). As these fingers probe the thicker fluid, new appendages branch off. Collectively these tiny appendages help the two liquids mix together quickly without the aid of microfluidic devices.