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There is a growing body of evidence that suggests there are waves on Saturn's moon Titan.

This is based on readings from Nasa's Cassini spacecraft, which is in orbit around the gas giant planet and its moons.

And, if confirmed, would suggest Titan is even more Earth-like than thought, with a surprisingly active weather system.

Scientists at the American Geophysical Union in San Francisco say they may have spotted waves on Titan (illustration shown). Radar data from Cassini suggests there are tiny ripples on the moon. These are a mere 0.6 inches high and move at just 2.3ft per second

The evidence for the waves was reported by scientists at a meeting of the American Geophysical Union in San Francisco this week, reported Eric Hand for Science Magazine.

Based on flybys of Titan in the last six months, it seems that three separate seas of Titan may have waves on their surface.

And using radar from the spacecraft, scientists have even be able to estimate their size - a minuscule 0.6 inches (1.5cm) - with a speed of just 2.3ft (0.7 metres) per second.

The waves are not on 'watery' bodies like on Earth, but instead on lakes and seas of liquid hydrocarbons - composed largely of methane.

These are much more viscous than water on Earth, comparable almost to tar, so they likely move much less than our own oceans and lakes.

But regardless, any ripples on the surface - most likely waves - would have to be caused by wind, just like on Earth.

Spotting waves on the surface therefore suggests there is an active windy environment on Titan.

'To me, it's exciting,' said Nasa Chief Scientist Ellen Stofan. 'It says that Titan is a dynamic place.'

Other results from Cassini also revealed the depths of some of its largest bodies.

Kraken Mare, for example, is thought to be 525ft (160 metres) deep, while Ligeia Mare could be up to 655 ft (200 metres) deep.

The existence of waves on Titan would confirm it has an active windy environment. 'It says that Titan is a dynamic place,' said Nasa's Dr Ellen Stofan. Titan, with its hazy atmosphere, is pictured here in front of the moon Tethys, which is seen in the background

The Cassini spacecraft, illustration shown, has been in orbit around Saturn and its moons since 1 July 2004. In June, the Cassini mission celebrated 10 years of exploring the planet. It arrived for a four-year mission but has since been continuously extended, although it will certainly end in 2017 when it runs out of fuel

In addition, some estimates suggest Ligeia Mare could contain 55 times the oil reserves of Earth.

And as radar was able to bounce off the sea bottoms, it suggests they are transparent and made mostly of methane, about 90 per cent, rather than ethane.

The evidence is also a boost for those that think Titan has some form of seasonal changes.

This was further evidenced last month when scientists used a wind tunnel on Earth to explain the appearance of sand tunes on Titan.

Based on their research, they estimate there are winds on Titan, and they increase in speed by 50 per cent on rare occasions.

This may occur when parts of it tilt towards the sun, with increased light causing winds to kick up.