Scientists have detected fluorescent biomolecules on the surface of Jupiter’s moon Europa, a potential biosignature that could indicate the presence of life beneath the icy crust. The discovery was made using laser-induced fluorescence, which can reveal the presence of organic molecules in ice.
Europa is believed to host a subsurface ocean in contact with a rocky mantle, where hydrothermal activity may drive the synthesis of organic molecules. Aromatic amino acids, which are building blocks of life, are unlikely to be formed abiotically, making their detection on Europa a significant finding.
However, surface bombardment by charged particles from the Jovian magnetosphere and solar ultraviolet radiation can degrade organic molecules, limiting their longevity. Researchers have modeled the effects of radiolysis and photolysis on these molecules and found that they are detectable in high-latitude regions using laser-induced UV fluorescence.
The study suggests that biosignatures contained within freshly deposited ice in these regions are effective in detecting organic molecules even from an orbiting spacecraft. This discovery has implications for future missions to Europa, such as the NASA’s Europa Clipper mission, which aims to explore the moon’s subsurface ocean and search for signs of life.
The researchers used data from the Galileo spacecraft to model the degradation mechanisms on Europa and found that radiolysis by electrons is the most effective mechanism in certain regions. This information can help scientists plan future missions and better understand the conditions necessary for life to exist on Europa.
Source: https://astrobiology.com/2025/03/fluorescent-biomolecules-detectable-in-near-surface-ice-on-europa.html