Is this the best place to find aliens in our solar system? Jupiter’s moon Europa is found to have the key ingredient for life in its salty ocean

By William On Sep 22, 2023

Scientists have found carbon dioxide (CO2) for the first time on Europa, Jupiter’s fourth largest moon.

The chemical compound, known to be abundant on Earth, was detected by NASA’s James Webb Space Telescope on the frozen surface of the moon.

It may have come from the vast ocean that is thought to lie beneath its icy shell, suggesting it could have been produced by life forms.

CO2 is known as one of the most important building blocks of life, as it is the primary carbon source for all living things, at least on our planet.

Europa is described as one of the few locations in our solar system with liquid water, along with Earth and Saturn’s moon Enceladus, making it an interesting target for astrobiologists.

Pictured is Jupiter’s moon Europa, where an ocean hidden beneath miles of ice is considered a prime candidate for extraterrestrial life. Scientists have found carbon dioxide (CO2) on Europe’s surface and the next step is to determine where it comes from

Scientists are almost certain that beneath Europa’s icy surface lies a saltwater ocean with about twice as much water as Earth’s global ocean. Image shows a possible model of Europe

Europe: Fast Facts

Europa is 90 percent the size of Earth’s moon.

It orbits Jupiter at a distance of about 484 million miles (778 million kilometers).

It completes one orbit around Jupiter every 3.5 Earth days.

The surface of Europa consists largely of solid water ice, criss-crossed by fractures.

But the subsurface ocean can hold more than twice as much water as Earth.

The moon has a very thin oxygen atmosphere – too thin for humans to breathe.

If there is life beneath the moon’s shell – which is believed to be about 10 miles (16 kilometers) thick – it could be adapted to survive in extremely cold temperatures.

These life forms can be very small, such as ‘extremophile’ microbes that are invisible to the naked human eye.

Researchers have published their new results in two separate investigations in the magazine Science.

“On Earth, life loves chemical diversity—the more diversity, the better,” says Geronimo Villanueva of NASA’s Goddard Space Flight Center in Greenbelt, Maryland.

‘Understanding the chemistry of the European ocean will help us determine whether it is hostile to life as we know it, or whether it might be a good place for life.’

Scientists are almost certain that beneath Europa’s icy surface lies a saltwater ocean with about twice as much water as Earth’s global ocean.

But it has been difficult to determine whether this hidden ocean has the right chemical elements to support life.

To find an answer, the US researchers used data from the Webb Telescope’s near-infrared spectrometer (NIRSpec) to map CO2 on Europa’s surface.

NIRSpec can measure the near-infrared spectrum of more than 100 objects simultaneously to reveal more about their properties, including temperature, mass and chemical composition.

Most of the CO2 emissions occurred in a 1,800 kilometer wide area called Tara Regio, where there is a lot of ‘chaos terrain’: areas with jagged edges and cracks.

Graphic shows a map of the surface of Europa with NIRCam (Near Infrared Camera) in the first panel and compositional maps derived from NIRSpec/IFU (Near Infrared Spectrograph’s Integral Field Unit) data in the next three panels

Webb’s NIRCam took this photo of the surface of Jupiter’s moon Europa. Webb identified carbon dioxide on Europa’s icy surface that likely came from the moon’s subsurface ocean. This discovery has important implications for the potential habitability of the European ocean. The moon appears mostly blue because it is brighter at shorter infrared wavelengths

The disturbed surface ice suggests that an exchange of material has taken place between the subsurface ocean and this icy outer shell.

What exactly causes chaos in the terrain is not yet well understood, but one theory is that warm water rises from the ocean and melts surface ice, which then refreezes over time into new, uneven rocks.

The scientists don’t think the CO2 came from anywhere other than the ocean below, for example by hitching a ride on a meteorite that crashed into the moon.

But the researchers cannot rule out that carbon emerged from the planet’s interior in the form of rocky carbonate minerals, which could then have broken down through irradiation and become CO2.

Samantha Trumbo, a planetary scientist at Cornell University and lead author of the study, told AFP that the carbon “ultimately came from the interior, probably the internal ocean.”

Previous observations with James Webb’s predecessor Hubble Space Telescope show evidence of ocean salt in the Tara Region.

This makes the area significantly yellower than the rest of Europe’s scarred white plains

The James Webb Space Telescope (JWST, pictured here in space) is the largest and most powerful space telescope ever built

The experts had also hoped to find plumes of water or volatile gases shooting out of the moon’s surface, but were unable to detect any.

To determine with certainty what lies beneath Europa’s ice cover, it may eventually be necessary for a satellite to land on the moon and drill through it.

However, scientists may be able to learn some fundamental things about the ocean’s composition before we “drill through the ice to get the full picture,” Villanueva said.

Two major space missions plan to take a closer look at Europa and its mysterious ocean, although both are orbiters, meaning they won’t land on it.

The European Space Agency’s Jupiter moon probe Juice launched in April, while NASA’s Europa Clipper mission is expected to launch in October 2024.

WHAT DO WE KNOW ABOUT EUROPE AND WHY IS IT SO SPECIAL?

Jupiter’s icy moon Europa is slightly smaller than Earth’s moon.

Europa orbits Jupiter every 3.5 days and, like Earth’s moon, is tidally locked, so the same side of Europa always faces Jupiter.

It is thought to have an iron core, a rocky mantle and a surface ocean of salt water, like Earth.

Unlike on Earth, however, this ocean is deep enough to cover the entire surface of Europa, and because it is far from the sun, the ocean surface is frozen worldwide.

Many experts believe that the hidden ocean surrounding Europa, warmed by powerful tidal forces caused by Jupiter’s gravity, may have conditions favorable for life.

NASA scientists are about to investigate Jupiter’s ocean moon Europa for signs of alien life.

Europa is our best chance to find biological life in the solar system, researchers say.

The space agency is preparing two probes, including one that will land on the surface, to explore the distant moon in detail over the next decade, the space agency says.