How were Uranus satellites named

Exploration of the Universe Part 4: Uranus and Neptune

Neptune: the invisible planet

Neptune is the eighth and outermost planet in our solar system and can never be seen with the naked eye from Earth. In contrast to the other planets, the discovery of Neptune is not based solely on observations of the night sky. A first indication of its existence were observed disturbances in the orbit of Uranus, which suggested the existence of an eighth planet. Based on these orbital disturbances, the French astronomer Urbain Jean Joseph Le Verrier calculated the position of this hypothetical planet in 1846 and sent his results to the observatory in Berlin. Shortly after the results arrived, it was confirmed that the calculations were correct and that an eighth planet actually existed: Johann Gottfried Galle and Heinrich Louis d'Arrest actually discovered a celestial body at the position specified by Le Verrier that had not previously been shown on the star maps was noted.

Another argument about a name

As with Uranus, naming the new planet was not easy. At times Janus and Oceanus were up for debate, and France suggested naming the planet after Le Verrier, which was vehemently rejected abroad. Le Verrier himself suggested naming the new planet after Neptunus, the Roman god of the sea. This name was in line with the mythological names of the other planets and was soon accepted internationally.

Another Uranus?

In many of its properties, Neptune is similar to Uranus. With a diameter of almost 50,000 kilometers, Neptune is similar in size to Uranus and after this the fourth largest planet in the solar system. The distance to the earth is always at least 4.3 billion kilometers and it takes the planet about 165 years to orbit the sun.

Unlike Uranus, however, Neptune only has a slightly inclined axis of rotation. The deviation from the plane of the orbit is 28.32 degrees, which roughly corresponds to the inclination of the earth's axis of 23.5 degrees. Since Neptune rotates at a similar speed as Uranus - it completes one revolution around itself in just under 16 hours - it too has a flattened shape at the poles.

The bluest planet

The atmospheres of Uranus and Neptune are composed similarly. The main components of both are hydrogen and helium. Like the high atmosphere of Uranus, the upper layers of Neptune's atmosphere also contain methane gas. This and another as yet unidentified atmospheric component give the Neptune its intense deep blue color.

In terms of their internal structure, Uranus and Neptune are also very similar. In the Neptune atmosphere, too, the pressure rises with increasing depth beyond the critical point, so that no clear surface can be defined. It is believed that Neptune has a solid core of rock and metal that is similar in size and mass to Earth.

The core is surrounded by a mantle made of rock, water, ammonia and methane. Although it is a hot and very dense liquid, like Uranus, this mixture is called ice due to its composition.

Choppy and stormy

While the weather on Uranus can be described as rather calm, the Neptune atmosphere is constantly changing. Although the planet is extremely far from the Sun, storms with extremely high wind speeds occur on Neptune. Peak values ​​of up to 2,100 kilometers per hour were measured. What drives these violent storms is not yet fully understood.