NASA published images of the aurora in Uranus / Geektimes

Polar lights

The aurora Borealis, northern or southern lights, just aurora. This very phenomenon is very beautiful, it arises as a result of the glow of the upper layers of the planet’s atmosphere due to interaction with charged particles of the solar wind. Polar lights are characteristic not only of the Earth, but also of Jupiter, Saturn, and also, as recently emerged, for Uranus.

This gas giant is not written about so often, as the attention of the scientific community is more attracted to Jupiter and Saturn. These planets are closer to Earth than Uranus, to observe them is easier. But NASA believes that it is necessary to study all objects of the solar system, regardless of their remoteness from the Earth. Therefore, NASA and ESA scientists regularly monitor Uranus.

Uranium is the third largest planet in the Solar System. The largest is Jupiter, the second largest is Saturn. Uranium is smaller than its nearest “competitor” by 25,362 km in diameter. Compared to the Earth, Uranus is very large, if it was hollow, 63 Earth could be placed inside this container. At a distance, the gas giant looks like a blue ball. If you observe it from a closer distance, you can see clouds and other atmospheric objects and phenomena. In addition, Uranus even has rings, although not as noticeable as those of Saturn. The slope of the axis of rotation of Uranus is 97 degrees. Perhaps, scientists believe, this can be explained by the fact that the gas giant has faced a smaller planet in the distant past.

NASA’s pictures show a bright aurora in the clouds of Uranus, which are in the upper layers of its atmosphere. Earlier, scientists observed a radiance on Jupiter and Saturn, but never – on Uranus. Due to the unusual configuration of its magnetosphere, auroras on this gas giant can arise only in the specific position of the planet relative to the Sun.

The first image of Uranus of acceptable quality was sent to Earth by Voyager 2 in 1986. Then he aspired to the edge of the solar system, which the device left just a couple of years ago. During the flight of the device past Uranus on the gas giant was the solstice. At this point, the axis of rotation of the planet was facing the Sun, the magnetic poles were in a position that was close to the configuration of the Earth’s poles. As a result, a rather large angle was formed with respect to the solar wind flow. All this allowed the polar aurora to appear on the night side of Uranus.

According to Lauren Lamy from the Paris Observatory, the structure of the magnetosphere of Uranus is unique for the solar system. Because of this, observations of the polar radiance of the planet are difficult. Such observations must be carefully planned, waiting until the configuration of the magnetosphere is optimal, and the coronal ejection of the Sun will come to Uranus. It is a cloud of high energy particles and causes auroras.

As for the aurora, it was recorded on Uranus with the help of the Hubble telescope in 2014. The same pictures helped to see the rings of Uranus. In the observations, scientists used the STIS tool (Space Telescope Imaging Spectrograph). Hubble became the first telescope, with the help of which it was possible to see the radiance in Uranus. Later observations of the aurora on this gas giant were carried out several more times.

Polar lights on Saturn, combined shot in the ultraviolet and visible light (Hubble Space Telescope) Nasa

It is interesting that the aurora scientists observed on the Venus with Mars, the nearest neighbors of the Earth. And on Venus and Mars there is no strong magnetic field. Therefore, on the first planet mentioned, the radiance manifests itself in the form of light diffuse spots of various shapes and intensities. Sometimes the radiance affects the entire planetary disk of Venus. Here they appear as a result of collisions of the electrons of the solar wind and the atmosphere of the planet, so that they can be well seen on the night side. On Mars, the radiance was first discovered on August 14, 2004 by the SPICAM instrument on board the Mars Express. The total size of the section of the atmosphere with this phenomenon was about 30 kilometers in diameter and 8 kilometers in height.