Uranus: From an Astronomical Perspective

Uranus, covered in blue haze, consists of immense gases—hydrogen, helium, and methane—which give the planet its color. The planet’s blue appearance is caused by the methane in the upper layers of its atmosphere that absorbs red light. It has a frozen and hazy atmosphere with a temperature that drops as low as −215°C. Uranus has a mass about 15 times that of Earth and a volume 100 times that of Earth.

If we were to take a closer look at Uranus, we could say that it was a motionless planet, as calm and serene as a pool. But looks can be deceiving. Despite its appearance, Uranus is a planet with many interesting qualities. Its atmosphere changes depending on the seasons, its magnetic field is lopsided, its rings are unlike those of any other planet, and it rotates on its side.

Uranus consists of ten dark and clear-cut rings as sharp as blades. These rings are eccentric, and they are situated quite far apart from each other. Its magnetic field, on the other hand, is truly odd and extremely volatile. Its magnetic axis is tilted at 60° from its axis of rotation, and it does not pass through the center of the sphere. Thus, the pole that we call the north pole of rotation is the magnetic south pole, and polar lights are mostly seen around its equator rather than its poles.

Another intriguing quality of Uranus is that it is tilted. This is believed to be caused by the gravity of Uranus’s enormous neighboring planets or a collision with another planet. Imagine the chaos that would ensue if we tilted the Earth on its side! Uranus has an axial tilt of 97.9°, which is over 90°. While most planets in the solar system rotate almost perpendicular to the ecliptic on their own axes, the rotational axis of Uranus is nearly parallel to the ecliptic, like a gigantic target board. This indicates that Uranus has retrograde rotation. Many questions about this motion are yet to be answered by scientists.

Gülden Bulut, What Sky Tells, Cosmopublishing