Utilizing NASA’s Juno spacecraft, scientists have calculated the speed of oxygen manufacturing on Jupiter’s moon Europa — the primary time any spacecraft had straight measured charged oxygen and hydrogen particles from the moon’s environment. From these measurements, the staff decided the speed of oxygen manufacturing to be a lot decrease than estimated in earlier research.
Europa, Jupiter’s fourth largest moon, has a rocky inside and a floor made from water ice. Measurements of the moon’s magnetic subject, collected by NASA’s Galileo mission, supplied proof for the presence of a salty ocean beneath the ice sheets. Ocean worlds, like Europa, are the prime candidates within the seek for extraterrestrial life in our photo voltaic system.
“Again when NASA’s Galileo mission flew by Europa, it opened our eyes to the complicated and dynamic interplay Europa has with its setting. Juno introduced a brand new functionality to straight measure the composition of charged particles shed from Europa’s environment, and we couldn’t wait to additional peek behind the scenes of this thrilling water world,” stated lead creator Jamey Szalay of Princeton College in New Jersey. “However what we didn’t understand is that Juno’s observations would give us such a decent constraint on the quantity of oxygen produced in Europa’s icy floor.”
On Sept. 29, 2022, Juno noticed Europa when it flew by at an altitude of 353 kilometers. It used its Jovian Auroral Distributions Experiment (JADE) instrument to measure charged particles that trailed the moon in its orbit round Jupiter.
Illustration displaying charged particles impacting Europa’s floor, splitting water molecules from the moon’s icy crust into hydrogen and oxygen molecules. The inset depicts how these oxygen molecules might migrate to the ocean under. (Credit score: NASA/JPL-Caltech/SWRI/PU)
“Europa is like an ice ball slowly dropping its water in a flowing stream. Besides, on this case, the stream is a fluid of ionized particles swept round Jupiter by its extraordinary magnetic subject,” defined Szalay. “When these ionized particles influence Europa, they break up the water-ice molecule by molecule on the floor to provide hydrogen and oxygen. In a approach, your complete ice shell is being constantly eroded by waves of charged particles washing up upon it.”
With Juno’s observations, the staff decided the speed at which hydrogen was produced on the moon’s floor. The method that splits the water molecules within the ice produces hydrogen and oxygen molecules in a two-to-one ratio. From this, the scientists estimate the whole oxygen manufacturing on Europa at round 12 kilograms per second.
“Earlier than Juno, earlier estimates ranged from just a few kilograms per second to over 1,000 kilograms per second,” stated Szalay. “The findings unambiguously show oxygen is constantly produced within the floor, only a good bit decrease than we anticipated.”
The staff believes that a few of the produced oxygen might discover its approach by means of the ice sheet into the oceans under, the place it might probably help life. Nonetheless, they estimate the speed at which this occurs to be lots decrease than urged in earlier research.
Juno carried out the measurements as a part of its prolonged mission. The spacecraft was launched in 2011 and arrived at Jupiter in 2016. After Juno accomplished its prime mission in July 2021, NASA approved a mission extension to 2025, or till the spacecraft’s finish of life.
“We designed JADE to measure the charged particles that create Jupiter’s auroras,” stated co-author Frederic Allegrini of Southwest Analysis Institute (SwRI) in San Antonio, Texas. “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 fantastically.”
By its prolonged mission, Juno contributes to the objectives of future missions to the Jovian system. The authors of the brand new paper state that their findings have essential implications for the European House Company’s Jupiter Icy Moons Explorer (Juice) mission and NASA’s upcoming Europa Clipper.
Illustration displaying the orbits for Juno’s prime and prolonged missions. (Credit score: NASA/JPL-Caltech/SwRI)
Juice, which launched on April 14, 2023, is scheduled to reach at Jupiter in 2031. To get there, it’s going to fly by Earth and Venus a number of occasions to carry out so-called gravity help maneuvers. The primary of which, an Earth-Moon flyby, is ready to occur this summer time.
At Jupiter, Juice will research Europa and two different ocean-bearing moons, Ganymede and Callisto, with its 10 science devices. Throughout two flybys, Juice will measure the thickness of Europa’s ice crust and scout places for potential future exploration.
Europa Clipper is presently being examined forward of its launch on a SpaceX Falcon Heavy, scheduled for October 2024. After it arrives in 2030, the spacecraft will use its 9 science devices to check Europa’s habitability throughout 49 flybys. The present research’s authors recommend that the observations made with one in every of these devices, the Plasma Instrument for Magnetic Sounding instrument, are affected by the brand new findings.
Collectively, these missions will assist scientists perceive ocean worlds and the way they might probably help life.
“Europa is a captivating object as a result of scientists are assured a liquid ocean exists in its inside,” stated co-author Robert Ebert of SwRI. “Water is essential for the existence of life and will be present in or on objects with various traits. Europa is an effective place to seek for water inside our photo voltaic system.”
Szalay et al.’s research was revealed within the journal Nature Astronomy on March 4.
(Lead picture: Europa imaged by Juno throughout its flyby on Sept. 26, 2022. Credit score: NASA/JPL-Caltech/SwRI/MSSS/Kevin M. Gill)
