Stormy Uranus Takes Astronomers By Surprise

[zavvy]

<b>Stormy Uranus Takes Astronomers By Surprise </b><br /><br />LINK<br /><br />Uranus may not be “the most boring planet” in the solar system after all - new images suggest the outer planet experiences weird seasonal weather patterns.<br /><br />When the space probe Voyager 2 visited the planet in 1986, its surface was virtually featureless. But that view has changed dramatically with recent images showing a large number of dynamic storm systems.<br /><br />In fact, a single image of Uranus taken in 2004 shows 18 distinct cloud systems - eight more than Voyager saw during its entire months-long flyby. And one set of images taken with the Keck II telescope in Hawaii in summer 2004 shows an extremely bright cloud reaching up high above the planet's opaque methane layers in its southern hemisphere.<br /><br />"We have never seen such vigorous convective activity in the southern hemisphere before," says Imke de Pater of the University of California, Berkeley, who used the Keck II telescope to obtain the images. The difference may be a reflection of the change of seasons, but since the Uranian year is as long as 84 Earth years it will take several decades to confirm this.<br /><br /><br />Midsummer days <br /><br /><br />It was midsummer in the planet’s southern hemisphere when Voyager visited, and because Uranus is tipped over on its side - its axis is inclined 98 degrees compared with Earth's 22.5 degrees - the entire hemisphere was in constant sunlight. Now, the spring equinox is approaching, so the Sun is nearly above the equator and the whole planet is going through a day-night cycle. The resulting changes in warming may be driving an increasingly active weather system, de Pater and colleague Heidi Hammel suggest.<br /><br />Until 10 years ago, the only pictures sharp enough to show any cloud features were those from Voyager. But then images from the Hubble Space Telescope began to exceed Voyager's re

 

[alkalin]

Could this be partly the result of more and larger comet/meteor hits as of late? Just a thought.

 

[yg1968]

I am surprised to see that earth telescope images can sometimes surpass those of Hubble. Before Voyager visited Uranus in 1986, there was no quality pictures of Uranus by any telecope or spacecraft. What has changed in the last few years? Why are telescopes so much better today?

 

[alkalin]

The reason for large telescopes in space, such as Hubble, was to avoid atmospheric turbulence. Keck II uses new technology of adaptive optics which can null most of the effects of atmospheric turbulence, as evidenced by these fine images. Building large telecopes on the Earth’s surface allows much larger apertures than could ever be put in space as well, and is a very great advantage.

 

[jindivik]

sorry can't resist .... Uranus is stormy! hehehe <img src="/images/icons/smile.gif" />

 

[hansolo0]

LoL. I wonder if Uranus is closer lately to the sun and/or it's other axis is pointing to the sun and that is doing it?

 

[alkalin]

Actually, Uranus was a god who was the personification of Heaven, regarded as the husband or son of Gaea (Earth) and father of the Titans, Furies, and Cyclopes: he was overthrown by his son Cronus (Saturn).<br /><br />Oops, whrong book........<br />