Lord of the rings: Cassinis view of Saturn

This stunning picture of Saturn, released yesterday, was taken from a spacecraft at a distance of a mere 69m miles.

Cassini-Huygens is a joint European-Nasa space mission due to go into orbit around Saturn in just 207 days. It will spend four years exploring the planet and its moons – and it will drop a package of instruments on to the surface of the moon Titan.

“Saturn is very much the lord of the rings and it is great to see that Cassini’s final destination is in sight,” said Carl Murray, of Queen Mary College London, one of the international team analysing the images from the spacecraft’s cameras. “Our views of the Saturn system are just going to get better and better as the Cassini spacecraft prepares to become Saturn’s first artificial satellite next July.”

Wesley Huntress, one of the Nasa team that launched the mission but now at the Carnegie Insti tution of Washington’s geophysical laboratory, said: “So far away, so long to travel, so much effort to make it happen – and so worth it.”

The picture – showing some details of the planet’s massive ring system, and five of its icy moons – was taken on November 9. Saturn’s main rings – bands of ice, dust and rock – have a thickness of only a few tens of metres but they span more than 16875 miles. This is about three quarters of the distance from Earth to the moon. Although the im ages were taken through blue, green and red spectral filters, the final colour is very close to what the human eye might see, if such a voyage were ever possible. The subtle colours of the planet could be caused by sulphur and nitrogen mixed into the thick clouds of ammonia in the planet’s freezing atmosphere. Most of its northern hemisphere is in the shadow of the rings.

The last such pictures were taken by Voyager 2 in 1981. Cassini- Huygens set off six years ago, and has been speeding through space at 13.75 miles per second, paying a visit to Jupiter along the way. It has so far covered 2bn miles. Carolyn Porco, now leader of the imaging science team, was involved in the original Voyager mission. She said: “This is turning out to be a very sentimental journey. I’m reminded of what it felt like to see Saturn’s rings for the first time with Voyager, and how rich and surprising they were.”

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