NASA’s Spitzer Probes Weather on Brown Dwarfs

New observations from NASA’s Spitzer Space Telescope suggest that most brown dwarfs are roiling with one or more planet-size storms.

Swirling, stormy clouds may be ever-present on cool celestial orbs called brown dwarfs. New observations from NASA’s Spitzer Space Telescope suggest that most brown dwarfs are roiling with one or more planet-size storms akin to Jupiter’s “Great Red Spot.”

“As the brown dwarfs spin on their axis, the alternation of what we think are cloud-free and cloudy regions produces a periodic brightness variation that we can observe,” said Stanimir Metchev of the University of Western Ontario, Canada. “These are signs of patchiness in the cloud cover.”

Brown dwarfs form as stars do, but lack the mass to fuse atoms continually and blossom into full-fledged stars.

Scientists think that the cloudy regions on brown dwarfs take the form of torrential storms, accompanied by winds and, possibly, lightning more violent than that at Jupiter or any other planet in our solar system. However, the brown dwarfs studied so far are too hot for water rain; instead, astronomers believe the rain in these storms, like the clouds themselves, is made of hot sand, molten iron or salts. Above: an artist’s conception of such a storm.

Metchev is principal investigator of the brown dwarf research. Other researchers include Étienne Artigau of Université de Montréal, Canada, and Bertrand Goldman of the Max Planck Institute for Astronomy, Germany.

For more on the brown dwarf research, see this NASA press release.