Astronomers admire 'Lord of the Rings'

Saturn has the most dramatic ring system of any planet

By BBC News Online science editor Dr David Whitehouse

A new image of Saturn - the "Lord of the Rings" - shows just how quickly ground-based telescopes are catching up with those in space.

The stunning image was taken by a new detector that corrects for distortion introduced by the Earth's turbulent atmosphere.

The Paranal Observatory is in its testing phase

It is connected to one of the new large telescopes at the Paranal Observatory in Chile.

When observed, Saturn was 1,209 million kilometres (751 million miles) away, with its ring system almost fully displayed.

The image is among the sharpest ever obtained from the ground and compares well with some photos obtained from space.

Much larger telescopes can be built on the ground for a fraction of the cost of building and launching a much smaller telescope into space. Astronomers believe removing the blurring introduced by the atmosphere is a good way forward.

Remarkable world

Scientists are excited by the detail seen in the image of Saturn, especially the intricate, banded structure of its atmosphere and rings.

A dark spot is visible at the south pole at the bottom of the image.

One of Saturn's moons, Tethys, is visible as a small point of light below the planet. It was used to guide the telescope and to perform the "refocusing" required to remove atmospheric distortion.

Technically, the observation was difficult because of the motion of Saturn during the exposure.

Strange world: Io

To provide the best possible pictures, the telescope system was pointed towards the Saturnian moon Tethys, while the image of Saturn was kept at a fixed position on the detector.

The dark spot close to the South Pole measures approximately 300 km (190 miles) across. It was only recently observed from the ground with a telescope at the Pic du Midi Observatory in the Pyrenees, France.

The bright spot seen close to the equator is the remnant of a giant storm in Saturn's atmosphere that has lasted more than 5 years.

Jupiter's moon Io was also observed. Io has a diameter of 3,660 km (2,270 miles) and orbits Jupiter every 42.5 hours. Strange volcanoes were detected on it by the Voyager spacecraft in 1979. It is, in fact, the most volcanic place known in the Solar System.

The new Io images show the broad pattern of volcanism on the moon and will allow astronomers to monitor the surface activity of this remarkable world.