Jupiter Moon Europa's Crusty Ice Shell May Have Underwater Snow Floating Up

A strange Earth phenomenon occurs when submerged snow rises upwards beneath ice shells. Jupiter's moon Europa, which has a worldwide subsurface ocean behind a thick ice cover, might also be experiencing a similar scenario.

Scientists said per News9Live that underwater snow forms submerged ravines and inverted ice peaks under the ice shell by floating upward inside the subsurface ocean.

The procedure is thought to be part of how the ice crust forms. It is believed that Europa's icy shell contains less salt than previously thought because underwater snow is significantly purer than other types of ice.

Jupiter Moon Europa

According to recent research published in the August edition of the journal Astrobiology, the frozen crust of Europa may have been partially formed by "frazil ice." This is a fluffy buildup of ice crystals that similarly includes underneath ice sheets on Earth.

This frazil ice contains just a small portion of the salt present in the ice that forms on the ice shelf, raising the possibility that Europa's ice sheets have less salt than previously thought.

Study lead author Natalie Wolfenbarger, a graduate student researcher at the University of Texas Institute for Geophysics, explained in a statement: "When we're exploring Europa, we're interested in the salinity and composition of the ocean, because that's one of the things that will govern its potential habitability or even the type of life that might live there."

Despite Europa's tremendous distance from the Sun, which places it well outside our star's habitable zone-the region where liquid water may exist on a planet's surface-Inverse said the moon's massive ocean swirls beneath its ice cover.

Hubble Finds Evidence of Persistent Water Vapor in One Hemisphere of Europa

(Photo: NASA, NASA-JPL, University of Arizona)
This photograph of the Jovian moon Europa was taken in June 1997 at a range of 776,700 miles by NASA's Galileo spacecraft. Slightly smaller than Earth's moon, Europa has a very smooth surface, and the solid ice crust looks like a cracked eggshell. The interior has a global ocean with more water than found on Earth. It could harbor life as we know it. Hubble Space Telescope observations of Europa have revealed the presence of persistent water vapor in its very tenuous atmosphere. Hubble observations, spanning 1999 to 2015, find that water vapor is constantly replenished throughout one hemisphere of the moon. This is a different finding from Hubble's 2013 observations that found localized water vapor from geysers venting from its subsurface ocean. This water vapor comes from a different process entirely. Sunlight causes the surface ice to sublimate, transitioning directly into gas. This color composite Galileo view combines violet, green, and infrared images. The view of the moon is shown in natural color (left) and enhanced color designed to bring out subtle color differences on the surface (right). The bright white and bluish part of Europa's surface is composed mostly of water ice, with very few non-ice materials.

ALSO READ: Jupiter's Moon, Natural Satellite Prevents Planet From Making Stunning Ring System Unlike Saturn

Instead, the continual stretching and compression the tiny moon experiences as it travels in an elliptical orbit around the much more massive Jupiter is known as tidal heating and is the source of this ocean's existence.

Io and Ganymede, Jupiter's moons, the first and third Galilean satellites, respectively, continuously pull on Europa. This tidal heating causes friction in Europa's core, which generates heat and eventually melts the inner ice to form the planet's vast ocean.

About Jupiter Moon Europa

One of the solar system's most interesting objects for astrobiologists is Europa.

NASA pointed out that the said moon is covered in an ocean that is 40 to 100 miles (60 to 150 kilometers) deep and is topped by an ice crust that is 10 to 15 miles (25 to 25 km) thick.

The moon Europa is an attractive area to look for extraterrestrial life because, while being just 25 percent the size of Earth, its ocean on the surface may contain twice as much water as all of Earth's seas.

Live Science pointed out that Europa most likely has a small temperature gradient or minimal variation in temperature with depth like Antarctica. Frazil ice is fairly prevalent in these circumstances, Wolfenbarger discovered, especially in places where the ice thins in rifts or fractures. If frazil ice often occurs on Europa, it may significantly alter the moon's ice shell's composition.

Frazil ice is far purer than congelation ice, which may include 10% of the salt in the saltwater around it. Frazil ice only contains 0.1% of the salt in the seawater it develops from. This low-salt ice may influence Europa's ice crust's strength and structure, as well as how successfully the radar of the Clipper can pierce the ice.