THE RINGS OF URANUS:
       In 1977, scientists tried to find the exact diameter of Uranus. They planned to do so by studying how long it took for the planet to cross in front of a specific star. As the scientists watched, they saw the star blink out for a moment. It blinked five times in all and then it passes out of view behind Uranus. As the star came back out, it blinked five times once again. This made the scientists realize that Uranus has rings.
       The Voyager 2 has shown that all of the giant planets have rings Uranus has eleven rings that circle the planet from top to bottom. The rings are named for letters of the Greek alphabet.
       All of the rings are the same flat, dark color. The dark color may come from black carbon coating the ice that makes up the rings or methane gas. While Saturn's rings are very bright and easily seen, it is puzzling why Uranus' is so dark. The rings reflect very little light and only five percent of the sunlight is reflecting back. Its rings are made of mostly ice boulders that are three feet across. They are very narrow and flat. The widest part of Uranus's last ring, the epsilon ring, is 60 miles across. The others are only 1 to 2 miles and barely half a mile deep. The distance between the rings varies between 208 miles and 1,784 miles.
       The material in the rings is kept from floating away by the gravitational force from the moons. A moon on each side of the ring has a gravitational pull that holds the rings in line. The moons seem to be made of the same material as the rings and are the same flat, dark color.

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THE CLOUDS:
       We see Uranus as an aquamarine planet. We see it as a blue planet because the reds and yellows in sunlight are absorbed by methane gas and only the greens and blues are reflected. The Voyager revealed very few clouds. However, the probe detected bands surrounding the planet. The bands are believed to be produced by convection currents. The lighter regions appear where warm material flows upwards and the darker areas appear where the cooler material flows downward.
       The few clouds that were seen indicate that there are strong winds on Uranus. The deep atmosphere is very cold since it is so far from the sun. The small amount of solar heat is spread from one place to another, most probably by the strong winds that blow constantly.

This picture of Uranus was processed to bring out the atmosphere, taken by the Voyager 2. 

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