James Webb Space Telescope has detected traces of carbon originating from the salty liquid oceans beneath the icy surface of Jupiter‘s moon, Europa. Scientists have long known that there are water oceans beneath Europa’s ice, but until now, they didn’t know if these oceans had the right chemistry to support life.
The discovery of carbon dioxide in this underground ocean has significant implications for the potential habitability of this moon. It is also further evidence of the innovative science made possible by the James Webb Space Telescope (JWST).
The foundational carbon building block of life
“On Earth, life thrives on chemical diversity. The more diverse, the better. Our life is based on carbon. Understanding the chemistry of Europa’s ocean will help us determine if it could be a good planet for life” said Geronimo Villanueva, lead author of the research. “This suggests that we may be able to learn some basic things about the ocean’s composition even before drilling through the ice”.
The team was able to use observations in the infrared spectrum with the Near-Infrared Spectrograph (NIRSpec) instrument on the JWST to determine that the carbon molecules were not transported to Europa through meteorite impacts or other external sources.
“We now believe we have observational evidence that the carbon we see on Europa’s surface comes from the ocean. This is not a trivial matter. Carbon is a biologically essential element” said Samantha Trumbo, lead author of the paper detailing this discovery (ref.).
The infinite possibilities of James Webb
James Webb observed that carbon dioxide around Europa is more abundant in a geologically young region called Tara Regio. The surface ice has been disrupted in this area, and material has been exchanged between Europa’s icy surface and its subsurface ocean.
“Previous observations from the Hubble Space Telescope showed evidence of ocean-origin salts in Tara Regio” Trumbo continued. “Now we see that carbon dioxide is also strongly concentrated there. We think this implies that carbon probably originates from the internal ocean”.
The observation of carbon on Europa is a testament to the power and utility of the James Webb Space Telescope. “These observations only took a few minutes of observatory time” added Heidi Hammel, who leads JWST observations in the Solar System. “Even in this short period, we were able to do science. This work is just a taste of what we will be able to do with James Webb in the Solar System”.
The results also have important implications for other future missions. In October 2024, NASA will launch the Europa Clipper spacecraft. The probe will travel to the Jovian moon system to conduct a detailed survey of Europa, to determine if its subsurface oceans could support life.
The results from the James Webb Telescope could also aid in the investigation of Jupiter and its moons in the European Space Agency’s (ESA) Jupiter Icy Moons Explorer (JUICE) mission. JUICE was launched in April 2023 on a 7.5-year journey to Europa and its other large Jovian satellites, Callisto and Ganymede, both of which host extensive oceans.
“This is an excellent first result of what James Webb will bring to the study of Jupiter’s moons” said co-author of the research and ESA researcher Guillaume Cruz-Mermy. “I look forward to seeing what else we can learn about their surface properties from these and future observations”.