What are the seasons like on Uranus?
At the summer equinox, the sun will be near the celestial pole of Uranus. As the Uranian year progresses, the sun will circle around the celestial pole and move further and further away, until it approaches the celestial equator in the Uranian Fall. This is the equinox. The sun will soon drop below the horizon for the duration of the winter. When the sun sets, you will be in continuous night for the next decade or two until the planet finally approaches Spring and the sun comes back to the celestial equator. • Why is the belt-zone circulation difficult to detect on Uranus? Uranus is very cold, so cloud layers form at a low level in the atmosphere. The upper part of the atmosphere is cloudless hydrogen gas and it obscures the cloud layers. The hydrogen gas participates in any belt-zone circulation, but its motion is difficult to detect because of the lack of clouds. • What is the escape velocity from the surface of an icy moon with a diameter of 20 km? (HINTS: The density of ice is 1 g/
