Juno spacecraft measures oxygen production on Jupiter’s moon

NASA’s Juno spacecraft has provided important data about charged particles in Europa’s atmosphere, revealing insights into the life-supporting potential of these particles. This research, which includes in situ measurements of oxygen and hydrogen, provides new information about Europa’s environmental conditions and the habitability of its subsurface ocean.

NASA’s Juno spacecraft directly measured charged oxygen and hydrogen molecules in the atmosphere of Europa, one of Jupiter’s largest moons. These observations are fundamental constraints on the potential oxygenation of the subsurface ocean, according to a new study co-authored by SwRI scientists and led by Princeton University.

One of the study’s authors, Juno principal investigator Dr. “These findings have direct implications for the potential habitability of Europa,” said Scott Bolton. “This study provides the first direct in situ measurement of water components in Europa’s atmosphere, giving us a narrow range that could support habitability.”

Juno’s flight to Europe

In 2022, “Juno” will complete the passage of Europe and approach the moon by 352 kilometers. The SwRI-developed Jovian Auroral Scattering Experiment (JADE) instrument aboard Juno detected the loss of significant amounts of charged molecular oxygen and hydrogen from the atmosphere.

SwRI scientist and co-author Dr. “For the first time, we were able to unambiguously detect hydrogen and oxygen using in situ measurements and also confirmed that Europa’s atmosphere consists primarily of hydrogen and oxygen molecules,” said Robert Ebert. .

The source of these molecules is believed to be water ice on Europa’s surface. Jupiter’s unstoppable radiation breaks molecular bonds of H ₂ It leaves behind oxygen and hydrogen. Heavier oxygen molecules remain more confined to the surface or surface atmosphere, while lighter hydrogen preferentially moves in and out of the atmosphere. Oxygen formed in ice is lost from the atmosphere and/or accumulates on the surface. Oxygen trapped in Europa’s ice could find its way into the subsurface ocean as a possible source of metabolic energy.

Oxygen production in Europe and its consequences

“Europe’s icy crust absorbs radiation, protecting the ocean beneath it. This absorption also produces oxygen within the ice, so the ice crust acts like Europa’s lungs, providing a potential oxygen source for the ocean,” said Princeton University scientist Dr. Jamie Saley. “We set narrow limits on total oxygen production in Europe, which is currently around 12 kg per second. Before Juno, previous estimates ranged from a few kg per second to over 1000 kg per second. The data obtained consistently showed slightly less oxygen at the surface than we expected.” “It clearly shows that it was produced.”

SwRI scientist and co-author Dr. “We designed JADE to measure the charged particles that create Jupiter’s auroras,” said Frederic Allegrini. “European flights were not part of Juno’s primary mission. JADE is designed to operate in a high-radiation environment, but is not required to operate in the European environment, which is constantly exposed to high levels of radiation. Regardless, the vehicle worked great.”

The new measurements contribute to a better understanding of Europe and its surroundings and open the door to new, more accurate models. For example, a new estimate of how much oxygen is produced on Europa’s surface could inform future studies of its subsurface ocean and potential habitability. These observations provide the first measurements of the composition of charged particles around Europa, providing an important new window into the complex interactions of moons with their environment.

“Europe is a fascinating object because scientists believe there is a liquid ocean deep within it,” Ebert said. “Water is important for the existence of life, it can be found in or on objects with different properties. Europa is a good place to look for water in our solar system.”