Massive Jupiter-like Storm Spotted on Dwarf Star

Jupiter’s Great Red Spot may not be a unique feature.

Writing in The Astrophysical Journal, astronomers say they have discovered a giant storm swirling on a distant, tiny star.

"The star is the size of Jupiter, and its storm is the size of Jupiter's Great Red Spot," said John Gizis of the University of Delaware, Newark. "We know this newfound storm has lasted at least two years, and probably longer."

The star, called W1906+40, was discovered in 2011 and is an “L-dwarf” star - meaning it is a relatively cool star. At 2,200 Kelvin, W1906+40 is cool enough “for clouds to form in its atmosphere.”

"The L-dwarf's clouds are made of tiny minerals," said Gizis.

The cloud the astronomers suspect is there would be large enough to fit three Earths and “rotates around the star about every nine hours.”

Over the course of two years, astronomers studied changes in the star’s atmosphere.

As is the case when a planet passes in front of its star, astronomers observed a dip in the light that was coming from W1906+40.

They said they knew the dips were not caused by planets, so they thought it might be because of a star spot similar to our sun’s sunspots. Spots can also cause a dip in the light emanating from the star.

Using infrared measurements, the astronomers determined the dip was being caused by the massive storm.

"We don't know if this kind of star storm is unique or common, and we don't know why it persists for so long," said Gizis, adding astronomers will look at similar stars to see if they, too, have storms.