Uranus, seventh planet from the Sun was visited by Voyager 2 in January 1986. Uranus always seems to be the butt of astronomers’ jokes, doesn’t it? But it was the first planet to be discovered since ancient times, the discovery was made by William Herschel in 1781. The blue-green colour of Uranus is due to methane in the atmosphere, the same gas that gives Neptune its dark blue colour. Uranus’ axis is tilted at an angle of 98 degrees, possibly due to a collision with another planet early in its history. This means that as it orbits the Sun, one pole is illuminated for half the time (42 Earth years), and then experiences 42 years of darkness. The moons and rings of Uranus are also tilted at the same angle.

Another oddity about the planet is that the magnetic field is misaligned with the centre (see diagram). Uranus has only been visited by Voyager two, which found it to have an extremely bland appearance setting it apart from the other gas giants which have visible bands of clouds and storms.

Diagram to show how the magnetic field of Uranus is off-set from its centre. (hehe).

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