A RARE edge-on alignment of Uranus鈥檚 rings as seen from Earth has revealed extensive changes since the Voyager 2 probe observed them in 1986.
Voyager 2 photographed Uranus鈥檚 major rings, thought to be made of chunks of rock, along with some wispy dust rings. In 2003, the Hubble Space Telescope revealed two new dust rings.
Imke de Pater of the University of California, Berkeley, and her team have now taken infrared images of the dust rings using the 10-metre Keck II telescope on Mauna Kea, Hawaii. They found that one dust ring seen by Voyager 2, called the zeta ring, seems to have disappeared altogether, while a new one has appeared in a zone that had previously looked empty (Science, ).
Advertisement
The changes reinforce the emerging view that ring systems are much more dynamic than previously thought. 鈥淲e used to think it was like studying geology,鈥� says team member Mark Showalter of the SETI Institute in Mountain View, California. 鈥淣ow we鈥檙e learning that studying them is more like studying weather.鈥�
