A giant, dark storm whirls through the upper atmosphere of a brown dwarf in this artist's concept. The brown dwarf, known as 2MASS 2139, is a "failed star" -- an object that is bigger than a planet, but not massive enough to shine as a star. Recent observations showed large changes in its brightness, suggesting that storms spin through its upper atmosphere, blocking some of its light. [Jon Lomberg]
Bitter storms roll across the northern U.S. at this time of year, with destructive winds and heavy snows. They can span hundreds of miles, socking in entire states.
Storms on some of the other planets in the solar system can make those on Earth look puny by comparison. The largest persistent storm is Jupiter’s Great Red Spot, which is about twice as wide as Earth and has been blowing for centuries. And last year, a storm on Saturn twisted all the way around the planet.
And an even bigger storm may have been spotted outside the solar system, in the atmosphere of a brown dwarf — an object that’s heavier than a planet, but not heavy enough to shine as a star. Its surface is quite hot, but still cool enough to allow clouds to form, as grains of dust stick together in its atmosphere.
The brown dwarf is known as 2MASS 2139. It’s several dozen light-years away, along the border of the constellation Aquarius, which is low in the southwest at nightfall.
As the brown dwarf rotates, it gets dramatically brighter and fainter. The researchers who made the observations suggest the change is caused by a giant storm in its atmosphere. It could be caused by dark clouds rotating into view, or by a hole in the clouds that allows the brighter surface below to shine through. Either way, the feature is far larger than the Great Red Spot. And that makes it the biggest single storm system yet seen — a monster swirling through the clouds of a failed star.
Script by Damond Benningfield, Copyright 2011
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