NASA’s Europa Clipper spacecraft is set to launch in October 2024 and begin its journey to the Jovian system.
There, it will orbit Jupiter and perform fly-bys of the gas giant’s icy moon Europa, which is thought to have a liquid ocean beneath its icy crust.
This makes it a prime target for planetary scientists interested in the search for life beyond Earth.
So does that make it some sort of oceanic paradise, where life might flourish and humans could one day live?
In a word, no. But that’s not the whole answer.
Scientists naturally remain guarded about Europa’s habitability.
“Science doesn’t have neat answers to questions,” says Bonnie Buratti of NASA’s Jet Propulsion Laboratory (JPL), Europa Clipper deputy project scientist.
“We’re not looking for life. We’re looking for habitable environments – areas where life could thrive.”
Europa’s habitability
Make no mistake: humans could not survive on Jupiter’s frigid moon Europa.
Hundreds of times colder than Earth’s coldest landscapes, bathed in radiation that would cook us within hours, gravitationally kneaded by Jupiter’s immense gravity and girdled by the thinnest whisper of an oxygen atmosphere, this is a blasted, inhospitable place – alien through and through.
Yet here on Earth, wherever we find water, we find life.
And Europa’s oceans might have twice as much water as ours.
As well as this, a recent study using data from NASA’s Juno spacecraft revealed that Europa produces 1,000 tonnes of oxygen every 24 hours.
“Life has evolved on Earth through a whole evolutionary process,” Buratti says.
Even in the deep ocean trenches, unreachable even for sunlight, there is life in geothermal vents – from extremophiles to burrowing worms to deep-sea fish.
“Not teeming with life,” Buratti admits, “but there are living things down there.”
And perhaps the hardy microbes found in Antarctica’s subglacial Lake Vostok afford the closest analogues to what hypothetical Europan life forms could look like.
But beyond that point of supposition, for now Europa’s slate remains blank.
“It’s really alien,” Buratti says. “We don’t know what it’s going to be like.”
This article originally appeared in the October 2024 issue of BBC Sky at Night Magazine.