$2bn project, yet to get funding approval, would look for life on Europa, which has vast ice-covered oceans of water.
The Europa Clipper would be the first dedicated mission to the waterworld moon, if it gets approval for funding from Nasa. The project is set to cost $2bn.
“On Earth, everywhere where there’s liquid water, we find life,” said Robert Pappalardo, a senior research scientist at Nasa’s jet propulsion laboratory in California, who led the design of the Europa Clipper.
“The search for life in our solar system somewhat equates to the search for liquid water. When we ask the question where are the water worlds, we have to look to the outer solar system because there are oceans beneath the icy shells of the moons.”
Jupiter’s biggest moons such as Ganymede, Callisto and Europa are too far from the sun to gain much warmth from it, but have liquid oceans beneath their blankets of ice because the moons are squeezed and warmed up as they orbit the planet.
“We generally focus down on Europa as the most promising in terms of potential habitability because of its relatively thick ice shell, an ocean that is in contact with rock below, and that it’s probably geologically active today,” Pappalardo said at the annual meeting of the American Association for the Advancement of Science in Boston.
In addition, because Europa is bombarded by extreme levels of radiation, the moon is likely to be covered in oxidants at its surface. These molecules are created when water is ripped apart by energetic radiation and could be used by lifeforms as a type of fuel.
For several years scientists have been considering plans for a spacecraft that could orbit Europa, but this turned out to be too expensive for Nasa’s budgets. Over the past year Pappalardo has worked with colleagues at the applied physics labat