Europa, one of Jupiter’s largest moons, has fascinated scientists for decades because it may hide a vast ocean of liquid water beneath its thick icy surface.
Since liquid water is one of the key ingredients needed for life, Europa is considered one of the most promising places in our solar system to search for signs of life beyond Earth.
However, a new study published in Nature Astronomy suggests that reaching this hidden ocean—or even studying water that comes from it—may be much more difficult than scientists once believed.
The research was led by Lujendra Ojha, an associate professor in the Department of Earth and Planetary Sciences at Rutgers University.
His team used computer simulations to investigate whether water from Europa’s deep underground ocean could travel upward through cracks in the ice and collect in shallow pools closer to the surface.
If these shallow reservoirs were directly connected to the ocean below, they would provide a much easier target for future spacecraft. Instead of drilling through many kilometers of ice, scientists might only need to study water trapped much closer to the surface.
But the new findings suggest this may not happen as easily as researchers had hoped.
The team found that liquid water rising from Europa’s ocean would likely cool and freeze before it could reach shallow layers of the ice. This means that any underground pockets of water discovered near the surface may not come from the deep ocean at all. Instead, they may have formed when parts of the ice shell melted locally.
This difference is important because scientists want to study Europa’s deep ocean to learn whether it could support life. If shallow water has a different origin, it may not reveal what is happening in the ocean hidden far below.
Europa’s ocean is thought to remain liquid because Jupiter’s powerful gravity constantly squeezes and stretches the moon. This movement creates heat inside Europa, preventing the ocean from freezing even though the surface is extremely cold.
Scientists have proposed that water could move upward through narrow cracks, called dikes, in the ice. The process is sometimes compared to the way molten rock travels through cracks inside Earth before erupting from volcanoes. On icy worlds like Europa, this is known as cryovolcanism, where water and ice take the place of lava.
The Rutgers team found that the water would likely move in a fast, turbulent flow rather than a smooth stream. As it rushes through the cracks, it would mix with the freezing cold walls of the ice, causing it to lose heat very quickly.
The water could even become “supercooled,” meaning it stays liquid even after dropping below its normal freezing point. Under these conditions, tiny ice crystals begin to form. These crystals can quickly build up and block the cracks, stopping the water from moving any farther.
According to the simulations, narrow fractures could freeze shut within just a few hours. Even larger cracks would struggle to carry enough water unless they were unusually large or existed in great numbers, which researchers believe is unlikely.
The findings arrive at an exciting time for planetary science. NASA’s Europa Clipper, launched in 2024, is expected to reach Jupiter in 2030 and will make dozens of close flybys of Europa. The European Space Agency’s JUICE (Jupiter Icy Moons Explorer) mission is also on its way and is scheduled to arrive in 2031.
Together, these spacecraft will study Europa’s icy shell, search for hidden water beneath the surface, and help scientists better understand the moon’s structure. The new study will also help researchers interpret whatever these missions discover.
While Europa remains one of the best places to search for life beyond Earth, the research suggests its deep ocean may be much more isolated than previously believed.
Even so, each new discovery is helping scientists better understand this mysterious moon and bringing us one step closer to answering one of humanity’s biggest questions: could life exist elsewhere in our solar system?
Source: KSR.
