Introductory text to the planet Uranus
Of the Uranus is the seventh planet in the solar system. It was not until 1781 that the German-British astronomer Friedrich Wilhelm Herschel discovered Uranus. The six inner planets, including Earth, have been known since antiquity, as they could be seen in the sky with the naked eye. Even with favorable constellations, Uranus is not in the sky as a planet. Rather, one might think that it is a star.
Named the planet, which is four times the size of the earth, according to Uranos, the Greek god of the sky. A day on Uranus takes 17 hours and 14 minutes. That's the time the planet needs to turn around its own axis. In contrast, a complete orbit around the sun takes 84 Earth years.
In pictures and observations with the telescope, the Uranus always shows in a greenish-blue color, whereby the tendency goes more into the blue color spectrum. Frozen methane in the upper gas envelope gives the planet its color.
Uranus - facts and figures
The image on the left does not show an upside down image because Uranus' axis tilt is 98 °. His rotation is declining. Only Mercury and Uranus are declining in the solar system. The cause is unknown until today. A collision with another protoplanet during the early phase of the universe is suspected.
Similar to Saturn, Uranus also has a ring system which, in contrast to the ring planet Saturn, is invisible to the naked eye. The rings essentially consist of dust and smaller rocks, probably from the moons of Uranus. Asteroid impacts have thrown this material into orbit. As a result, the strong gravitational field of Uranus attracted these objects, which have since revolved around the planet.
Uranus' gaseous surface consists of 84% hydrogen, 14% helium and 2% methane. The closer it gets to the center of the planet, the more pressure increases. Therefore, the gas at its critical point in the liquid state of aggregation over. The core of Uranus consists of ice and rock, possibly also heavier elements are involved.
The moons of Uranus
27 moons circling the Uranus: Ariel, Belinda, Bianca, Caliban, Cordelia, Cressida, Cupid, Desdemona, Ferdinand, Francisco, Juliet, Mab, Margaret, Miranda, Oberon, Ophelia, Perdita, Portia, Prospero, Puck, Rosalind, Setebos, Stephano, Sycorax, Titania, Trinculo and Umbriel. The names are almost all borrowed from figures from William Shakespeare's works. Noteworthy are the five main moons: Miranda, Ariel, umbriel, Titania and Oberon.
Titania is the largest of the Uranus moons with a diameter of 1500 km. Cupid with 10 km diameter the smallest Uranusmond. When summed up, the mass of the 27 Uranus moons gives just 20% of the Earth's mass.
Voyager 2 - On the way to the edge of the solar system
In 1977, the two spacecraft Voyager 1 and 2 launched their way to the edge of the solar system. For Voyager 2 was originally planned only to Jupiter and Saturn arrive. NASA did not expect the spacecraft to remain functional for such a long time to fly to other targets in the solar system, take pictures, and send them back to Earth. After successful mission, the probe was redirected towards Uranus and Neptune, where it flew by in 1986 and 1989 respectively. Since then, Voyager 2 continues to fly to the edge of the solar system. So far, more than 25,000,000,000 km have been covered. Voyager 1 and 2 are the Earth's farthest from Earth, and will remain so for now. So far, no further missions are planned. The majority of missions over the next 10 years will target Mars and our Moon.