There are massive storms erupting on Uranus and astronomers aren’t sure why.
“The weather on Uranus is incredibly active,” said Imke de Pater, leader of the team that spotted the activity.
“This type of activity would have been expected in 2007, when Uranus’s once-every-42-year equinox occurred and the sun shined directly on the equator,” said co-investigator Heidi Hammel of the Association of Universities for Research in Astronomy.
“But we predicted that such activity would have died down by now. Why we see these incredible storms now is beyond anybody’s guess.”
The team, led by de Pater, used the Keck Observatory in Hawaii to make the observations. Between August 5 and 6, the team spotted eight large storms on the planet’s northern hemisphere.
Even amateur astronomers got in on the fun. Marc Delcroix, a French amateur astronomer, managed to capture one of the bright storms in early October.
“I was so happy to confirm myself these first amateur images on this bright storm on Uranus, feeling I was living a very special moment for planetary amateur astronomy,” Delcroix said.
Check out the GIF below to see the bright spot as it moves across the planet’s face.
An image below from Anthony Wesley in Australia shows the storms on September 19, and again on October 2.
What’s interesting is the storm spotted by the amateur astronomers is not the same one seen by de Pater and his team. De Pater’s discovery was seen at 2.2 microns, a specific wavelength that shows clouds just below the lower boundary of the planet’s stratosphere.
The one spotted by Wesley and Delcroix was seen at 1.6 microns. This is light from deeper in the atmosphere.
“The colors and morphology of this cloud complex suggests that the storm may be tied to a vortex in the deeper atmosphere similar to two large cloud complexes seen during the equinox,” Larry Sromovsky, a planetary scientist at the University of Wisconsin, Madison, said.
Uranus’ storm is still active today, but it appears to have weakened.
The recent flurry of extreme storms on Uranus shows “how little we understand about atmospheric dynamics in outer planet atmospheres,” according de Pater and his team.
Image credits: UC Berkley, Marc Delcroix, Anthony Wesley