NASA has published pictures of auroras on Uranus

Polar Lights

The aurora borealis has several names: Aurora Borealis, northern or southern lights, simply aurora. This phenomenon itself is very beautiful, it occurs as a result of the glow of the upper layers of the planet’s atmosphere as a result of interaction with charged particles of the solar wind. Polar lights are characteristic not only for the Earth, but also for Jupiter, Saturn, and also, as it turned out recently, for Uranus.

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


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Uranus is the third largest planet in the solar system. The largest is Jupiter, the second largest is Saturn. Uranium is less than its nearest "competitor" by 25,362 km in diameter. Compared to Earth, Uranus is very large, if it were hollow, 63 Earths 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 will notice 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 in the distant past has encountered a smaller planet.

The pictures published by NASA show a bright aurora in the clouds of Uranus, which are located 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 occur only at a specific position of the planet relative to the Sun.

The first image of Uranus of acceptable quality sent Voyager 2 to Earth in 1986. Then he sought to the edge of the solar system, which the apparatus left a couple of years ago. During the passage of the apparatus by 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 is close to the configuration of the Earth's poles. The result was a fairly large angle with respect to the flow of the solar wind. All this allowed the aurora to appear on the night side of Uranus.

According to Loren Lamy of the Paris Observatory, the structure of the Uranus magnetosphere is unique to the solar system. Because of this, observing the aurora of the planet is difficult. Such observations have to be carefully planned, waiting until the configuration of the magnetosphere is optimal, and the coronal ejection of the Sun comes to Uranus. It is a cloud of high energy particles and causes auroras.

As for the aurora, it was able to fix it 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 tool STIS (Space Telescope Imaging Spectrograph). Hubble became the first telescope with which it was possible to see the aurora on Uranus. Later, observations of the aurora on this gas giant were made several more times.


Aurora on Saturn, a combined picture in the ultraviolet and visible light (Hubble Space Telescope)

Interestingly, scientists observed auroras on Venus and Mars, Earth’s closest neighbors. And on Venus and Mars there is no strong magnetic field. Therefore, on the first mentioned planet, auroras appear as 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 the collisions of electrons of the solar wind and the atmosphere of the planet, so that they can be viewed well on the night side. On Mars, auroras were first discovered on August 14, 2004 with the SPICAM tool aboard the Mars Express vehicle. The total size of the section of the atmosphere with this phenomenon was about 30 kilometers in diameter and 8 km in height.