Juice mission launches to look for possibility of life on Jupiter's moons

One of the most enduring questions about space is whether or not there is extra-terrestrial life in the Solar System.

A new ESA mission to Jupiter is hoping to find any possibility that other celestial bodies in the Solar System have the potential to support life. Blasting off from Europe's Spaceport in Kourou, French Guiana, the Juice mission will head for the moons Ganymede, Callisto and Europa.

Dr Helena Bates, a space researcher at the Museum who is not involved in the mission, says, 'The Juice mission is investigating some of the most intriguing bodies in the Solar System when it comes to the potential to support life.'

'It's a truly amazing mission which I think is going to change our understanding of habitability in our Solar System.'

The moons of Jupiter have been identified as having some of the highest potential to support life because some of them are known to have liquid oceans of water beneath their icy surface.   

Professor Carole Mundell is the Director of Science at ESA. She told the BBC, 'In every extreme environment on Earth, whether that's high acidity, high radioactivity, low temperature, high temperature - we find microbial life in some form.'

'If you look at the vents at the bottom of Earth's oceans, these even look like alien worlds. There's no reason why that microbial life should not be able to exist elsewhere, if we have similar conditions. And it's those conditions that we want to study with Juice.'

What is the Juice mission and what does it hope to find?

The Juice mission is the latest major project from ESA, hoping to study the moons of Jupiter to see if they are conducive for life.

The spacecraft will perform 35 passes within 400 kilometres of the surface of three of the gas giant's moons: Ganymede, Callisto and Europa. Eventually it will settle into orbit around Ganymede, where the 10 scientific instruments on board will take photographs, analyse the surface and map sub-surface features.  

From the detailed measurements taken scientists will have an unprecedented account of the moons' hidden oceans, particularly on Ganymede. The instruments will be able to reveal not only how deep the oceans are, but also the salt content, the depth of the crust and even if the ocean is in contact with the crust.

It is thought that if life were to exist somewhere in the Solar System, these moons would be a good candidate. 

'Even though the Jovian system is much further from the Sun than Earth, and temperatures are much colder, some of the moons of Jupiter are thought to have liquid water oceans,' explains Helena. 'This is because Jupiter is so big it produces incredibly strong tidal forces, stretching and squeezing its moons.'

'This process generates heat, which we think is enough to melt ice within these moons into liquid water. That's particularly important because on Earth, wherever you find liquid water you find life. So it is not a stretch to think that if there is liquid water on Ganymede, Callisto and Europa, that there might be the potential for life as well.'

The spacecraft will take a circuitous path to reach Jupiter. The Arianne-5 rocket attached to the satellite does not have enough power to send it directly to Jupiter within a useful timeframe, so it will first travel around the inner Solar System, performing a flyby past both Venus and Earth in order to get enough of a gravitational boost to sling it further out towards Jupiter.

This is expected to take Juice around eight years, with the satellite scheduled to reach its final destination sometime around July 2031.