Europa or frying pan? Which is Jupiter's moon?

One of the images is Jupiter's moon Europa. The rest are the bottoms of frying pans after many years of wear and tear.

Nasa's Europa Mission released nine images and invited members of the public to spot which is the intriguing satellite. (Scroll to the bottom for the answer)

Europa is the second of Jupiter’s large Galilean moons, and for the past few years it has been causing a great deal of excitement after the Hubble telescope picked up a cloud of water vapour erupting from its south pole.

Analysis of old data also revealed that the Europan surface is rich in organic compounds. It means that Europa could hold alien life.

Europa is about the same size as our Moon. Before the Voyager probes arrived at Jupiter in the eighties, it was thought that it would look like our Moon as well.

But images showed a body that looked like a huge white billiard ball – gleaming, smooth and almost no craters at all, suggesting a geographically active world whose surface was changing continually, wiping out evidence of meteor strikes.

Analysis showed that the surface was made of almost pure water ice and when Nasa's Galileo space probe sent back new images in June 1996 it revealed a landscape of icebergs apparently frozen into the sea, grooves and enormous rifts.

Now scientists think that Europa is a ball of rock overlain by a water ocean possibly a hundred miles deep, in turn covered by an active thin ice crust which periodically breaks up.

In June, the European Space Agency announced that is has joined forces with Airbus to develop a new space probe to look for extra-terrestrial existence on Jupiter's icy moons.

It will launch in 2022 and head for the ocean-bearing worlds of Europa, Ganymede and Callisto.

Dubbed the Juice (JUpiter ICy moons Explorer) spacecraft, the mission will look at whether the frozen worlds which surround gas giants could support extra-terrestrial life.

So far missions like Nasa’s Kepler have focussed on hunting for rocky planets like Earth, believing that they would be the best candidates for life. But the first images beamed back from Pluto by the New Horizons spacecraft earlier this month suggest that icy outer planets and frozen moons could be geologically active and hold liquid water.

It is hoped that micro-organisms or even fish-like creatures may be present in deep-water hydrothermal vents known as 'black smokers' which are known to harbour life on Earth.

Dr Daniel Brown, an astronomy expert from Nottingham Trent University, said: "All our current exciting and fascinating space missions have been dealing with either understanding the origins of life and our Solar System or finding exoplanets that might host Earth-like planets.

"But, life doesn’t have to exist on planets like Earth, it could also have developed in oceans within icy moons around Jupiter like gas giants."