Hubble Photographs Solar Eclipse on Uranus
The Hubble Space Telescope has captured a solar eclipse on the planet Uranus for the first time. Ariel, the largest moon closest to the planet, was responsible for this.
The moon moved between Uranus and the sun on its orbit in such a way that it cast a shadow on the cloud cover. However, this shadow was very small relative to solar eclipses on Earth, since Ariel is only a third the size of Earth's Moon, but Uranus is about four times the size of Earth.
Uranus has over twenty moons, including other larger ones such as Umbriel, Titania and Oberon. Solar eclipses on Uranus are still a rarity because the planet's axis of rotation is very sharply tilted and almost parallel to the plane of its orbit. In a Uranus year, the sun therefore alternately shines almost vertically on the two poles and only in between on the equator, which the moons orbit. Since it takes 84 years for Uranus to orbit the sun once, solar eclipses can only occur every 42 years.
2007 the sun's rays will hit the Uranus equator perpendicularly. So Hubble could soon get solar eclipses through the other moons in front of the lens.
