Juno spacecraft measures oxygen production on

SAN ANTONIO — March 5, 2024—NASA’s Juno spacecraft has instantly measured charged oxygen and hydrogen molecules from the ambiance of one in all Jupiter’s largest moons, Europa. Based on a brand new research co-authored by SwRI scientists and led by Princeton College, these observations present key constraints on the potential oxygenation of its subsurface ocean.

“These findings have direct implications on the potential habitability of Europa,” mentioned Juno Principal Investigator Dr. Scott Bolton of SwRI, a co-author of the research. “This research supplies the primary direct in-situ measurement of water elements present in Europa’s ambiance, giving us a slender vary that might help habitability.”

In 2022, Juno accomplished a flyby of Europa, coming as shut as 352 kilometers to the moon. The SwRI-developed Jovian Auroral Distributions Experiment (JADE) instrument aboard Juno detected important quantities of charged molecular oxygen and hydrogen misplaced from the ambiance.

“For the primary time, we’ve been capable of definitively detect hydrogen and oxygen with in-situ measurements and additional verify that Europa’s ambiance is made primarily of hydrogen and oxygen molecules,” mentioned SwRI Workers Scientist and co-author Dr. Robert Ebert.

The supply of those molecules is considered water ice on Europa’s floor. Jupiter’s rampant radiation breaks H₂O’s molecular bonds, forsaking oxygen and hydrogen. The heavier oxygen molecules stay extra constrained to the floor, or near-surface ambiance, whereas the lighter-weight hydrogen predominately escapes into the ambiance and past. Oxygen produced within the ice is both misplaced from the ambiance and/or sequestered within the floor. Oxygen retained in Europa’s ice may go its technique to its subsurface ocean as a doable supply of metabolic power.

“Europa’s ice shell absorbs radiation, defending the ocean beneath. This absorption additionally produces oxygen throughout the ice, so in a manner, the ice shell acts as Europa’s lung, offering a possible oxygen supply for the ocean.” mentioned Princeton College Analysis Scholar Dr. Jamey Szalay, the research’s lead writer. “We put slender constraints on the overall oxygen manufacturing at Europa presently at round 12 kg per second. Earlier than Juno, earlier estimates ranged from a number of kg per second to over 1,000 kg per second. The findings unambiguously reveal oxygen is repeatedly produced within the floor, only a good bit decrease than we anticipated.”

“We designed JADE to measure the charged particles that create Jupiter’s auroras,” mentioned SwRI Workers Scientist and co-author Dr. Frederic Allegrini. “Flybys of Europa weren’t a part of the first Juno mission. JADE was designed to work in a high-radiation setting however not essentially Europa’s setting, which is continually bombarded with excessive ranges of radiation. Nonetheless, the instrument carried out superbly.”

The brand new measurements contribute to a larger understanding of Europa and its setting, open the door for newer, extra exact fashions. The research’s new estimation of how a lot oxygen is produced inside Europa’s floor, as an illustration, might inform future analysis associated to its subsurface ocean and potential habitability. As these observations present the primary charged particle composition measurements inside Europa’s neighborhood, they supply an essential new window into the moons’ complicated interplay with its setting.

“Europa is an interesting object as a result of scientists are assured a liquid ocean exists in its inside,” Ebert mentioned. “Water is essential for the existence of life and may be present in or on objects with various traits. Europa is an efficient place to seek for water inside our photo voltaic system.”

The paper “Oxygen manufacturing from dissociation of Europa’s water ice floor,” seems in Nature Astronomy: https://www.nature.com/articles/s41550-024-02206-x.

For extra data, go to https://www.swri.org/planetary-science.