Solar activity affects the brightness of Uranus

Changes in solar activity affect the color of the clouds of Uranus and their density, found researchers from Oxford University and Reading University, both scientific institutions of Great Britain.

This ice planet is the second planet in the counting of the solar system from the outer edge and makes one revolution around the sun in 84 years – so long one Uranian year.

The researchers, led by Karen Aplin of Oxford University, found that if one takes into account the long and unusual times of the year of this planet, then its brightness increases and decreases with the frequency of 11 years. This is how much the solar activity cycle continues, which also affects the number of sunspots.

Dr. Uplin said: “The atmosphere of Uranus is one of the coldest in the solar system, but it still contains clouds and ice, as well as in the atmosphere of our planet.”

“Changes in the brightness of the planet show that something is happening with these clouds. We found that these changes are related to two main processes. ”

“One of these processes is of a chemical nature and is associated with changes in the intensity of ultraviolet radiation emitted by the Sun, which affect the color of particles present in the atmosphere of Uranus. The second process involves high-speed particles called cosmic rays that come to our solar system from different parts of the universe. The flow of these particles bombards the atmosphere of Uranus and also influences the formation of clouds in it. Solar activity determines the flux of cosmic rays, since our star has a magnetic field that transmits more or less cosmic radiation, depending on the activity of the Sun, determined in turn by its 11-year cycle. ”

In their work, the researchers used data collected with the Voyager 2 spacecraft (Voyager 2).