The first images of the rings of the planet Uranus from a ground telescope show a system of rings that have changed since the first pictures were taken 20 years ago, a new report states.
Looking at the rings, astronomers found that dust envelops the entire ring system but is not connected with any particular ring. The dust pattern has also changed greatly since the rings were first photographed by the Voyager spacecraft in 1986. In 1986, the dust appeared to be embedded in the rings; current pictures show a cloud of dust that runs throughout the ring system. Researchers suggest that such changes may be common in the solar system and occur on much larger scales than expected.
Uranus is the seventh planet from the Sun and it is the third largest planet in our solar system. Its mass is about 15 times that of Earth, and its year – the time it takes the planet to travel around the Sun once – equals 21 Earth-years.
When William Herschel discovered the planet in 1789 he thought he saw a ring around it and noted it. In 1977 the rings were “re-discovered” by researchers in an airborne observatory. As the spaceship Voyager 2 whizzed past Uranus in 1986, it took the first images of the approximately one dozen rings.
Astronomer Imke de Pater and coworkers used the telescope at the W.M. Keck Observatory in Hawaii to make the first ground-based images of the rings.
The current view of Uranus from Earth is unusual – the plane of Uranus’ rings appear edge-on to the Earth in August 2007 and the angle reveals the unlit side of the rings. This allows astronomers to see faint rings that cannot be easily seen in the bright light. By looking at the planet from its dark side, these hard-to-see rings are brightened by scattered light. This study appears in the 23 August issue of Science Express.-American Association for the Advancement of Science
Comment and add to the story without registration, but keep the comments meaningful please. Links are not accepted.
