Physical Science:

Uranus [Figure 12.1.8] is the seventh planet from the Sun and is an ice giant planet, meaning it has a predominantly icy and gaseous composition. It has a unique feature among the planets in our solar system in that its axis of rotation is tilted at an extreme angle of 98 degrees relative to its orbit, which means that the planet appears to be rotating on its side. Uranus is the third-largest planet in our solar system and has a system of rings, although they are much less prominent than the rings of Saturn. Uranus also has at least 27 known moons, with the largest ones being Miranda, Ariel, Umbriel, Titania, and Oberon. The atmosphere of Uranus is predominantly composed of hydrogen and helium, with small amounts of methane, which gives the planet its blue-green color. Uranus is a relatively cold planet, with an average temperature of about -195 degrees Celsius (-320 degrees Fahrenheit) at its cloud tops. The planet has only been visited by one spacecraft, Voyager 2, which flew by in 1986 and provided us with our best data and images of Uranus to date.