America's Voyager-Two spacecraft flew past the planet Uranus two weeks ago today. The spacecraft is already many millions of kilometers past the planet.
But scientists say they have only started their study of the huge amount of information Voyager-Two has sent back to Earth. The scientists say this information so far shows Uranus is very different from anything else we have studied in our solar system.
Uranus is one of the most distant planets orbiting the Sun. Only Neptune and Pluto are farther away. It is one of the largest planetsfour times bigger around than earth.
Until the Voyager visit, scientists did not know a great deal about Uranus. And they say they still are not able to explain Voyager's discoveries.
Information from Voyager shows that the winds on Uranus blow in the same direction as the planet turns. This is exactly the opposite of what is found on Earth. Earth and most other planets turn, or rotate, like a spinning toy. Uranus rotates on its siderolling through space like a giant ball.
Voyager discovered that the dark side of Uranusthe side away from the sunis warmer than the side facing the sun. The rings around Uranus are very darknot bright like the rings around Saturn. The Saturn rings are mostly small particles. But Voyager found the rings around Uranus are mostly large rocksone meter across, or bigger.
Voyager's pictures also show the moons orbiting Uranus are very blacklike huge pieces of coal. Not all of them are dead, icy rocks. Some of the Uranus moons seem to have a great deal of geological activity. Voyager's instruments found that Uranus had a thick atmosphere of hydrogen, with clouds of methane. The atmosphere is bitterly coldabout two hundred degrees below zero, Celsius.