The Cassini spacecraft has taken its first image of Saturn, even though it is still 20 months away from arriving at the ringed planet.

This is an emotional event for the mission

Dr Dennis Matson

The colour composite image was taken from a distance of 285 million kilometres (177 million miles), nearly twice the distance between the Earth and the Sun.

The image shows the shadow of the planet falling across its famous rings and includes Saturn's largest moon, Titan.

"Cassini has sighted the ringed planet looking distant, mysterious and serene," said Dr Carolyn Porco, the leader of the science team using the Cassini camera.

"Our anticipation has been building for years, so it's good to know our destination is in view."

Summer in south

The mission to the sixth planet is a joint venture between the US, European and Italian space agencies.

Cassini has already flown by Jupiter

Cassini will go into orbit around Saturn on 1 July, 2004, and will release a piggybacked probe, Huygens, to descend through the thick atmosphere of Titan on 14 January, 2005.

Cassini has already sent back impressive images of Jupiter en route to Saturn, but scientists and engineers are clearly excited to have their main goal now in view.

"This is an emotional event for the mission," said Cassini project scientist Dr Dennis Matson. "We now have Saturn in our sights."

In the new image of Saturn, the planet's southern hemisphere is experiencing its summer.

Early Earth

The Sun is 27 degrees below the equator and casts a semi-circular shadow of the planet on the rings.

Huygens will drop down into Titan's atmosphere in 2005

The last Saturn-bound spacecraft, Voyager 2, arrived in early northern spring. Many features seen in Voyager images - spoke-like markings on the rings, clouds and eddies in the hazy atmosphere, ring-shepherding moons - are not yet visible to Cassini.

The planet's major moon, Titan, appears in the upper left of the picture.

The satellite is a major attraction for scientists on the mission.

When they get close enough, the researchers will study the moon's haze-enshrouded atmosphere and peer down, with special instrumentation, to its surface to look for evidence of organic processes similar to those that might have occurred on the early Earth, prior to the emergence of life.