Juno Mission Discovers Europa’s Icy Moon Generates 1,000 Tons of Oxygen Daily
In a groundbreaking discovery, NASA’s Juno mission to Jupiter has revealed that Europa, one of Jupiter’s icy moons, generates a staggering 1,000 tons of oxygen every day. This finding, published in Nature Astronomy on March 4, challenges previous estimates and sheds light on the moon’s potential for supporting life.
Europa, the fourth largest of Jupiter’s 95 known moons, has long intrigued scientists due to its ice-covered surface and the possibility of a vast subsurface ocean. The latest research indicates that Europa’s icy shell is continuously eroded by charged particles from Jupiter’s radiation belts, which split water molecules on the moon’s surface into hydrogen and oxygen.
“Europa is like an ice ball slowly losing its water in a flowing stream. Except, in this case, the stream is a fluid of ionized particles swept around Jupiter by its extraordinary magnetic field,” explains Jamey Szalay, a scientist from Princeton University involved in the study. “When these ionized particles impact Europa, they break up the water-ice molecule by molecule on the surface to produce hydrogen and oxygen. In a way, the entire ice shell is being continuously eroded by waves of charged particles washing up upon it.”
To measure the rate of oxygen production on Europa, Juno’s Jovian Auroral Distributions Experiment (JADE) instrument collected data on hydrogen outgassing from the moon’s surface during a close flyby on September 29, 2022. The analysis revealed that Europa generates approximately 26 pounds (12 kilograms) of oxygen per second. This estimate is significantly lower than previous studies, which ranged from a few pounds to over 2,000 pounds per second.
The implications of this discovery are immense. Scientists believe that some of the oxygen produced on Europa may find its way into the moon’s subsurface ocean, potentially serving as a source of metabolic energy. Combined with the presence of a salty water ocean beneath its icy crust, Europa’s oxygen production further enhances the moon’s potential for hosting life-supporting conditions.
The significance of Europa’s location in Jupiter’s radiation belts cannot be overstated. Charged particles from the gas giant bombard Europa’s surface, creating oxygen and hydrogen molecules. While the oxygen may migrate towards the subsurface ocean, the hydrogen is likely lost to space due to its lightness.
Scott Bolton, Juno’s principal investigator from the Southwest Research Institute, emphasizes the importance of Juno’s observations in unraveling Europa’s mysteries. “Back when NASA’s Galileo mission flew by Europa, it opened our eyes to the complex and dynamic interaction Europa has with its environment,” says Bolton. “Juno brought a new capability to directly measure the composition of charged particles shed from Europa’s atmosphere, and we couldn’t wait to further peek behind the curtain of this exciting water world.”
The Juno spacecraft, equipped with 11 state-of-the-art science instruments, continues to explore the Jovian system. While the recent findings on Europa’s oxygen production are groundbreaking, there is still much to learn. NASA’s upcoming Europa Clipper mission, set to arrive at Jupiter in 2030, will investigate various facets of Europa’s habitability using a sophisticated payload of nine science instruments.
As Juno sets its sights on another Jovian moon, Io, scientists anticipate gathering valuable data on its volcanic activity. On April 9, Juno will come within approximately 10,250 miles (16,500 kilometers) of Io’s surface, adding to previous flybys that have provided insights into this intriguing moon.
The Juno mission continues to push the boundaries of our understanding of Jupiter and its moons. With each new discovery, scientists inch closer to uncovering the secrets hidden within our solar system’s most enigmatic celestial bodies.