Evidence of prolonged steam in the hemisphere of Europe, the icy moon of Jupiter

Astronomers have highlighted the continued presence of steam in Europe by the Jovian ice-cold satellite based on observations from NASA’s Hubble Space Telescope. However, researchers still do not understand why this vapor exists only in one hemisphere.

Searching for traces of life within the solar system is an area of ​​study in its own right, and many good places have been identified relatively close to home, one of which is Europe. In fact, this natural satellite of Jupiter hides a vast ocean beneath its icy surface, providing all the favorable conditions for life.

Previously, scientists had already detected steam around Europe, but In the form of plums exploding through the ice. They are similar to the geysers on Earth, but extend at an altitude of almost 100 kilometers. They create volatile explosions of steam in the lunar atmosphere, the surface pressure of which is only one billionth of that of the Earth’s atmosphere.

Part of the mystery persists

However, these new results show that steam was spread over a large part of Europe during Hubble’s observations between 1999 and 2015. This indicates the long-term presence of the vapor atmosphere. “Europe’s hemisphere (always opposite the direction of its motion in its orbit). The cause of the asymmetry between the front hemisphere and the rear hemisphere is not fully understood. Geophysical Research Letters.

To achieve this result, astronomers carefully analyzed archival images and the Hubble Spectra using a promising new technique. In particular, it recently helped the same researcher Lawrence Roth, the Royal Institute of Technology KDH (Sweden), to detect water vapor in the atmosphere of Gonimet (another moon on Jupiter).

⁇ Observing the vapor behind GoneMite and Europe improves our understanding of the ice moon atmosphere Roth said in a NASA statement. “ However, since the surface temperature of Europe is lower than that of barley, the finding of a constant water surplus in Europe is somewhat more surprising than that of barley. .

You should be aware that Europe reflects more sunlight than granite, which has a surface below 15 C above granules. The maximum daytime temperature in Europe is -127 C. However, even at these low temperatures, new observations show that water is at the peak of ice – going directly from the solid to the vapor, without the liquid state – on the surface of Europe, similar to canmeet.

Roth made the discovery by selecting European observations on UV dates from 1999, 2012, 2014 and 2015 when the Moon was in different orbits and exploring the Hubble Archives. All of these observations were made using the Hubble Space Telescope Imaging Spectrograph (STIS).

Ultraviolet observations of STIS helped Roth determine the abundance of oxygen (one of the components of water) in the European atmosphere, and by explaining the intensity of the emission at different wavelengths, he was able to determine the presence of vapor.

This discovery allows astronomers to better understand the atmospheric structure of icy moons in general, and to lay the groundwork for planned scientific work on the Jovian system, among other things, to determine whether an environment far from the sun still survives. This paves the way for in-depth exploration of Europe through future research, including the work of NASA’s Europa Clipper and the European Space Agency’s (ESA) Juice (Jupiter IC Moons Explorer).

NASA video showing the discovery:

Source: Geophysical Research Letters