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- Scientists discovered ammonia compounds The surface of Jupiter’s moon Europa. Why is this important?
- The compound probably came up from the ocean below, Through cracks in the ice surface. These can be evidence of active geology within the Earth’s crust or habitable conditions in the ocean.
- New analysis of old images from the Galileo mission Ammonia has been found to be deposited near large cracks in the Earth’s crust.
Ammonia in Europe: active geology and life?
Debate continues over whether Jupiter’s moon Europa can support life in its hidden ocean. One key is active geology, which could serve as the engine of life on worlds like Europa by linking this world’s internal chemistry to its oceans. But a recent study suggests that Europa’s ocean floor may not be like that. geologically active Enough to support life. And another study found that the necessary chemical nutrients may still be present. came from the icy crust of Europe. Perhaps they will penetrate the ocean and thus life will be activated. Now, new evidence has been found. NASA said A new analysis of old data was performed on January 29, 2026. galileo The mission first discovered ammoniaContains compounds on Europa’s surface. Ammonia is a nitrogen-containing molecule, and nitrogen is a fundamental building block of life.
Ammonia deposits are located near large cracks in the surface. This is where the ocean itself or smaller liquid water resides. lake within the ice crust – May appear on the surface.
Al Emran from NASA’s Jet Propulsion Laboratory in California is the author of the new paper. peer reviewed paper, published in Planetary Science Journal November 7, 2025.
NASA’s Galileo mission points to ammonia in Europe, recent research Showsastrobiology.com/2026/01/nasa… #Astrobiology @NASAScience_
— Astrobiology (@astrobiology.bsky.social) 2026-01-29T20:38:40.483Z
Old Galileo images reveal ammonia on Europa
Emran discovered deposits of compounds containing ammonia in old images taken by the Galileo spacecraft. Galileo explored Jupiter and its moons from 1995 to 2003. Until now, no one had noticed ammonia (NH3) deposits. But now, new sophisticated reanalysis of the images has revealed the deposits. The image at the top zooms in on an area approximately 250 miles (400 km) wide. Galileo acquired it in 1997 during its 11th orbit around Jupiter.
The pixelated shapes represent Galileo’s near-infrared mapping spectrometer (NIMS) musical instrument. Red pixels indicate the location of ammonia (also known as NH3) compounds, and purple pixels indicate that they were not detected.
paper state:
The presence of NH3-containing components on icy planetary bodies has important implications for their geology and potential habitability. Here we report on the detection of Europa’s characteristic NH3 absorption features, identified by observations with the Galileo near-infrared mapping spectrometer. Spectral modeling and band positions indicate that NH3 hydrate and NH4 chloride are the most plausible candidates.
Does ammonia come from the underground ocean?
The paper suggests that the most likely source of ammonia compounds is the underground ocean or other reservoirs within the ice crust. The compounds could reach the surface through cryovolcanism, which is volcanic activity that involves icy material instead of hot magma. Because ammonia cannot persist for long in space, or because it is present on Europa’s virtually airless surface, this suggests that it appeared on the surface relatively recently geologically. The paper reads:
I hypothesize that in Europa’s recent geological past, ammonia-containing materials were transported to the surface via extrusive cryovolcanism or similar mechanisms.
The transport of ammonia-bearing materials from underground sources provides insight into the composition and chemistry of Europa’s interior, suggesting that it has been chemically reduced. high pH and a thick ocean floor beneath a relatively thin shell of ice. Nevertheless, the detection of ammonia-containing components in this study provides the first evidence of nitrogen-bearing species on Europa, an observation of considerable astrobiological significance due to nitrogen’s fundamental role in the molecular basis of life.
Impact on livability
The discovery of ammonia provides another important clue as to its potential. livability European sea. Ammonia contains one nitrogen atom and three hydrogen atoms. It can be produced both biologically and abiotically (non-living).
The fact that it contains nitrogen makes it even more interesting. As we know, nitrogen is one of the important molecules necessary for life. Helps form amino acids, DNA, chlorophyll, and proteins.
Ammonia also lowers the freezing point of water. This means that water containing ammonia can remain liquid even at lower than normal freezing temperatures. This could be important in the case of Europa and other moons with subsurface oceans, even though scientists have found ammonia on a significant number of other icy bodies in the solar system, whether or not they have oceans.
It will be interesting to see what NASA does european clipper It will be discovered when it reaches Europa in 2030. Both the surface and interior of Europa will be studied in unprecedented detail. Will it show that Europe is a habitable world?
Conclusion: New analysis of images from the Galileo mission reveals ammonia deposits on Jupiter’s moon Europa. That could mean a geologically active crust and habitable oceans.
Source: Detection of NH3 absorption band at 2.2 um on Europa
Read more: Europa’s strange ‘spiders’ hint at water lurking below
Read more: Europa’s Juno images reveal complex, active surface