NASA's Hubble discovers new rings and moons around Uranus

[Whitters]

NASA's Hubble Space Telescope photographed a new pair of rings around Uranus and two new, small moons orbiting the planet.
http://www.astromart.com/news/news.asp?news_id=413

[Mike]

Astronomers have discovered that the planet Uranus has a blue ring - only the second found in the Solar System.

Like the blue ring of Saturn, it probably owes its existence to an accompanying small moon.

Scientists suspect subtle forces acting on dust in the rings allow smaller particles to persist while larger ones are recaptured by the moon.

Smaller particles reflect blue light, giving the ring its distinctive colour, the US team reports in Science.

All other rings - those around Jupiter, Saturn, Uranus and Neptune - are made up of both large and small particles, making the rings reddish in appearance.


read the FULL story here - http://news.bbc.co.uk/1/hi/sci/tech/4883848.stm

[Rick]

Astronomers have captured remarkable new images of the rings of Uranus.

The rings are currently edge-on to Earth, in an event that only happens every 42 years.

A team, led by Imke de Pater from University of California, Berkeley, US, has analysed the rings' structure, with some surprising results.

More: http://news.bbc.co.uk/2/hi/science/nature/6961087.stm

[Rick]

Uranus May Have Two Undiscovered Moons

NASA's Voyager 2 spacecraft flew by Uranus 30 years ago, but researchers are still making discoveries from the data it gathered then. A new study led by University of Idaho researchers suggests there could be two tiny, previously undiscovered moonlets orbiting near two of the planet's rings.

Rob Chancia, a University of Idaho doctoral student, spotted key patterns in the rings while examining decades-old images of Uranus' icy rings taken by Voyager 2 in 1986. He noticed the amount of ring material on the edge of the alpha ring -- one of the brightest of Uranus' multiple rings -- varied periodically. A similar, even more promising pattern occurred in the same part of the neighboring beta ring.

"When you look at this pattern in different places around the ring, the wavelength is different -- that points to something changing as you go around the ring. There's something breaking the symmetry," said Matt Hedman, an assistant professor of physics at the University of Idaho, who worked with Chancia to investigate the finding.

More: http://www.jpl.nasa.gov/news/news.php?feature=6657