More photos have been returned to Earth from NASA’s Juno spacecraft, showing the beauty of giant planet Jupiter and its small, lava-encrusted moon Io.
As the solar-powered spacecraft completed its 47th close flight (period) from Jupiter on Dec 14, it attempted to send its science data back to NASA, but the downlink was lost.
After an initial return of just one image — its volcanic moon Io — the rest of the raw data from Io and Jupiter appeared online on January 4th. Since then, a team of image processors – all dedicated volunteer “citizen scientists” – have posted a series of spectacular finished images online.
The delay was caused by a radiative part of Jupiter’s magnetosphere, according to NASA. Mission controllers from NASA’s Jet Propulsion Laboratory restarted the onboard computer and put the spacecraft into safe mode.
Juno’s images of I0 – the most volcanic body in the solar system – were taken when Juno was 40,000 miles away. The moon is believed to have an underground ocean of magma. Just before Juno approached Io, an eruption of volcanic activity began.
Io is in a constant gravitational tug of war with Jupiter and the other large moons, so much so that it actually changes shape during its 42-hour orbit. The constant stretching and squeezing is believed to cause frictional “tidal heating”.
This flyby of Io was Juno’s first of nine in the next few years, two of which will be just 1,500 kilometers away.
“The team is really excited that Juno’s expanded mission includes studying Jupiter’s moons. Each close flyby gave us a wealth of new information,” said Scott Bolton, Juno’s principal investigator at the Southwest Research Institute in San Antonio. “Juno sensors were designed to study Jupiter, but we were amazed at how well they could do double duty by observing Jupiter’s moons.”
Juno launched in 2011 and arrived at Jupiter in 2016. Since then, it has made 47 close flybys of the planet’s polar regions, most recently on December 15, 2022. It included the first of nine flybys of Io – the most volcanic body in the solar system – two of them from just 1,500 kilometers away.
The two super-close flybys will take place on December 30, 2023 and February 3, 2024. During this time, Juno will study Io’s volcanoes and study how volcanic eruptions interact with Jupiter’s strong magnetosphere and aurora.
The spacecraft is in a highly elliptical orbit, getting close to Jupiter’s moons and the planet’s polar regions only every five or six weeks when it turns on its two-megapixel camera.
Juno’s mission is to study Jupiter’s composition, magnetic field, and magnetosphere to measure water in its atmosphere and winds. It has discovered how Jupiter’s atmosphere works and revealed the complexity and asymmetry of its magnetic field.
Juno has also revealed the size of Jupiter’s “Great Red Spot,” which spans 200 miles/350 kilometers. The largest storm in the solar system lies 22º south of Jupiter’s equator and has been raging since at least 1830. Its diameter makes it almost twice the size of Earth.
The spacecraft also studied Jupiter’s “Great Blue Spot,” an isolated spot with an intense magnetic field near the planet’s equator.
In October 2021, new findings from Juno provided the first 3D look at how the giant planet’s “beautiful and violent atmosphere” works beneath the uppermost cloud layers.
It has also performed close flybys of Jupiter’s moons Europa and Ganymede, sending back over three terabits of scientific data in total so far.
However, the spaceship is now on an exciting expanded mission. After completing its standard five-year, 37-orbit survey of Jupiter in November 2021, Juno has been given a new life until 2025.
Although there may be another extension, if not then the 76th and last of the spacecraft period will be on September 15, 2025 when it will conduct a “death dive” in the gas giants. This will prevent it from accidentally crashing into one of Jupiter’s moons and potentially becoming contaminated.
Juno is the ninth spacecraft imaging Jupiter, the others are Pioneer 10 and Pioneer 11, Voyager 1 and Voyager 2, Galileo Orbiter and Galileo Probe, Ulysses and Cassini.
Juno’s next close flyby of Jupiter, period 48, taking place on January 22, 2023.
I wish you clear skies and big eyes.