NASA’s Juno will perform close flyby of Jupiter’s icy moon Europa

On Thursday, Sept. 29, at 2:36 a.m. PDT (5:36 a.m. EDT), NASA’s Juno spacecraft will come inside 222 miles (358 kilometers) of the floor of Jupiter’s ice-covered moon, Europa. The solar-powered spacecraft is predicted to acquire among the highest-resolution photos ever taken of parts of Europa’s floor, in addition to accumulate helpful knowledge on the moon’s inside, floor composition, and ionosphere, together with its interplay with Jupiter’s magnetosphere.

Such info may gain advantage future missions, together with the company’s Europa Clipper, which is ready to launch in 2024 to check the icy moon. “Europa is such an intriguing Jovian moon, it’s the focus of its personal future NASA mission,” mentioned Juno Principal Investigator Scott Bolton of the Southwest Analysis Institute in San Antonio. “We’re pleased to offer knowledge which will assist the Europa Clipper staff with mission planning, in addition to present new scientific insights into this icy world.”

With an equatorial diameter of 1,940 miles (3,100 kilometers), Europa is about 90% the dimensions of Earth’s Moon. Scientists assume a salty ocean lies under a miles-thick ice shell, sparking questions on potential circumstances able to supporting life beneath Europa’s floor.

The close flyby will modify Juno’s trajectory, decreasing the time it takes to orbit Jupiter from 43 to 38 days. It will likely be the closest a NASA spacecraft has approached Europa since Galileo got here inside 218 miles (351 kilometers) on Jan. 3, 2000. As well as, this flyby marks the second encounter with a Galilean moon throughout Juno’s prolonged mission. The mission explored Ganymede in June 2021 and plans to make shut approaches of Io in 2023 and 2024.

Information assortment will start an hour previous to closest approach, when the spacecraft is 51,820 miles (83,397 kilometers) from Europa.

“The relative velocity between spacecraft and moon will probably be 14.7 miles per second (23.6 kilometers per second), so we’re screaming by fairly quick,” mentioned John Bordi, Juno deputy mission supervisor at JPL. “All steps need to go like clockwork to efficiently purchase our deliberate knowledge, as a result of quickly after the flyby is full, the spacecraft must be reoriented for our upcoming shut strategy of Jupiter, which occurs solely 7 ½ hours later.”

The spacecraft’s full suite of devices and sensors will probably be activated for the Europa encounter. Juno’s Jupiter Energetic-Particle Detector Instrument (JEDI) and its medium-gain (X-band) radio antenna will accumulate knowledge on Europa’s ionosphere. Its Waves, Jovian Auroral Distributions Experiment (JADE), and Magnetometer (MAG) experiments will measure plasma within the moon’s wake as Juno explores Europa’s interplay with Jupiter’s magnetosphere.

MAG and Waves can even seek for attainable water plumes above Europa’s floor. “Now we have the precise tools to do the job, however to seize a plume would require a whole lot of luck,” mentioned Bolton. “Now we have to be on the proper place at simply the precise time, but when we’re so lucky, it is a house run for positive.”

Inside and Out

Juno’s Microwave Radiometer (MWR) will peer into Europa’s water-ice crust, acquiring knowledge on its composition and temperature. That is the primary time such knowledge could have been collected to check the moon’s icy shell.

As well as, the mission expects to take 4 visible-light photos of the moon with JunoCam (a public-engagement digital camera) throughout the flyby. The Juno science staff will examine them to photographs from earlier missions, on the lookout for modifications in Europa’s floor options which may have occurred over the previous twenty years. These visible-light photos could have an anticipated decision higher than 0.6 miles (1 kilometer) per pixel.

Though Juno will probably be in Europa’s shadow when closest to the moon, Jupiter’s ambiance will mirror sufficient daylight for Juno’s visible-light imagers to gather knowledge. Designed to take photos of star fields and seek for bright stars with identified positions to assist Juno get its bearings, the mission’s star digital camera (known as the Stellar Reference Unit) will take a high-resolution black-and-white picture of Europa’s floor. In the meantime, the Jovian Infrared Auroral Mapper (JIRAM) will try to gather infrared photos of its floor.

Juno’s closeup views and knowledge from its MWR instrument will inform the Europa Clipper mission, which can carry out practically 50 flybys after it arrives at Europa in 2030. Europa Clipper will collect knowledge on the moon’s ambiance, floor, and inside—info that scientists will use to higher perceive Europa’s world subsurface ocean, the thickness of its ice crust, and attainable plumes which may be venting subsurface water into space.