How Salt Ice Drips Nourish Europa’s Hidden Ocean

Salty Ice ‘Drips’ May Feed Europa’s Hidden Ocean, Study Finds

Europa’s surface looks frozen and scarred. Ice covers the moon in craters and cracks. Beneath it, scientists suspect a vast hidden ocean.

A new study suggests that this ocean may receive nutrients from above. The mechanism is unusual. Dense, salt-rich ice forms at the surface and slowly sinks downward like a drip.

Salt-Rich Ice Sinks Through the Shell

Researchers modeled an ice shell similar to Europa’s. They assumed a thickness of about 30 kilometers. The simulations showed that salty surface patches grow denser and weaker over time.

Under these conditions, the heavy ice detaches. Then, it begins a slow descent through the shell. Eventually, these blocks reach the bottom near the ocean.

The team found that every modeled surface layer could sink this way. In fractured ice, the process could start in about 30,000 years. In solid, intact ice, it could take 5 to 10 million years.

Scientists compare this to a process on Earth. There, dense parts of the crust sink into the mantle. This is known as lithospheric foundering.

Feeding the Hidden Ocean

As the ice sinks, it carries surface materials with it. These include oxidants and chemical nutrients formed by radiation at the surface. When the ice reaches the ocean, it releases these ingredients.

This creates a steady supply line from surface to sea. Over geological time, the process could repeat again and again. Therefore, the ocean may not be chemically isolated after all.

Study lead author Austin Green says this idea solves a key problem. Scientists have long wondered how Europa’s ocean could receive nutrients. This model offers a practical pathway.

He adds that this is “a good sign for the prospects of extraterrestrial life.” If nutrients reach the ocean, habitability increases.

Europa Clipper Will Investigate

NASA launched the Europa Clipper mission in 2024. The spacecraft will reach Europa in 2030. It will perform dozens of flybys to study the ice shell and the ocean below.

These observations may confirm whether this sinking process occurs. If proven, it would change how scientists view icy moons across the solar system.