Storm-like activity found on distant brown dwarfs

Makes Great Red Spot look like a 'small squall'

Earlier this year, astronomers snapped one of the first optical images of a brown dwarf, arrow, around a parent star.

(CNN) -- Scientists announced this week they have detected atmospheric conditions on objects orbiting other stars, seeing the effects of torrential storm clouds that in some ways resemble those on Earth and our planetary neighbors.

The deep space meteorologists conducted their studies of celestial bodies known as brown dwarfs, which are more massive than gas planets like Jupiter but smaller than stars.

The discovery, conducted by a team from NASA and the University of California, Los Angeles (UCLA), could help scientists better understand weather conditions on other planets and brown dwarfs in other star systems.

"The best analogy to what we witness on these objects are the storm patterns on Jupiter," said Adam Burgasser, a UCLA astronomer involved in the study, in a statement. "But I suspect the weather on these more massive brown dwarfs makes the Great Red Spot [a conspicuously large storm on Jupiter] look like a small squall."

Brown dwarfs, which lack the mass and fuel to ignite into stars, exhibit strange behavior as they cool, Burgasser and colleagues noticed. Using scientific calculations, they determined that breaks or holes in the cloudy atmosphere explained the mystery.

Scientists theorized that the bodies should grow increasingly faint as they lose heat. But for a brief time during the cooling process they were observed to become brighter.

The reason is clouds, according to the scientists. Brown dwarfs have temperatures as high as 3,140 degrees Fahrenheit (1,730 degrees Celcius), which would evaporate iron and sand into gas.

As the brown dwarfs cool, the gases condense into droplets to form clouds, much like water clouds on our planet. As storm winds break holes in the clouds, bright infrared energy from the lower atmosphere shines through, which accounts for the unexpected brightening spurts on brown dwarfs, the scientists said.

"While many groups have hinted that clouds structures and weather phenomena should be present, we believe we have actually shown that weather is present and can be quite dramatic," Burgasser said.

The findings, to be published in the June 1 edition of the Astrophysics Journal Letters, could help scientists figure out the composition of atmospheres on planets and planet-like bodies orbiting other stars.

"Brown dwarfs have traditionally been studied like stars, but it's more of a continuum," said co-author Mark Marley of NASA's Ames Research Center in Moffett Field, California.

"If you line a mug shot of Jupiter up with these guys, it is just a very low-mass brown dwarf," he said.

In recent years, scientists have identified nearly 100 planets in other star systems, most of them significantly larger than Saturn. As observatories on the ground and in orbit become more powerful in the coming decades, they hope to find planets as small as our own.