The most recent objective of Juno’s extended mission is the innermost moon of Jupiter.
When the Juno spacecraft from NASA arrived in the Jovian system in 2016, it was given the mission of conducting in-depth research on the largest planet in the solar system. It goes without saying that Jupiter is the planet with the greatest number of moons in the solar system (by a hair), and Juno has had the opportunity to observe a handful of those moons as well. During its most recent flyby, it was able to capture the stunning sulfuric appearance of the volcanic moon Io.
In order for the spacecraft to do research on Jupiter, it must continue to orbit in a highly eccentric orbit. Because of this, the amount of time that Junop spends in close proximity to the gas giant, which generates powerful bands of radiation that have the potential to destroy the electronics of the probe, is reduced. As a result of their lengthy and sweeping orbits, Juno is typically located in close proximity to the inner moons of the planet. The spacecraft Juno has previously completed flybys of the planets Ganymede and Europa. In the year 2022, there was yet another flyby of Io, but this time the spacecraft came within a distance of 64,000 kilometers (40,000 miles). The spacecraft Juno flew over the surface of the Earth on December 30 at a height of only 1,500 kilometers (930 miles).
Io is the third largest planet in the Jovian system, even though it is somewhat larger than the moon that orbits the Earth. Tidal heating is caused by the steady pull of Jupiter’s gravity, which has resulted in the formation of an amazing 400 active volcanoes on the moon. These volcanoes emit plumes of sulfur and sulfur dioxide. You can see some significant volcanic features in the image that is shown above, including the mountain that is the largest on the entire moon. It is Loki Patera, who is represented by the dark circle off to the lower right. A lava lake can be found within this depression that is 202 kilometers (126 miles) in length. This lake demonstrates evidence of periodic surface modifications.
It has been twenty years since scientists have had the opportunity to examine Io in greater detail, and they are hoping that this mission may shed some light on the planet’s interior. “Juno will investigate the source of Io’s massive volcanic activity, whether a magma ocean exists underneath its crust, and the importance of tidal forces from Jupiter, which are relentlessly squeezing this tortured moon,” explains Scott Bolton of the Southwest Research Institute (SwRI). “They will also investigate whether or not there is a magma ocean underneath its crust.”
The JunoCam instrument aboard our #JunoMission acquired six images of Jupiter's moon Io during its close encounter today. This black-and-white view was taken at an altitude of about 1,500 miles (2,500 kilometers). More images will be available soon at https://t.co/mGfITRe57Y pic.twitter.com/9GcamrhxPt
— NASA Solar System (@NASASolarSystem) December 31, 2023
The JunoCam instrument has captured a total of six fresh observations of Io, and all of the raw photos that were captured by the instrument have been uploaded to the website of the expedition. Considering the severe radiation environment, NASA did not anticipate that JunoCam would be able to survive the entirety of the mission; nonetheless, it is still functioning normally. The SwRI, which is in charge of managing the mission, has reported that the camera has begun to exhibit a drop in its dynamic range as well as an increase in its noise.
Engineers at SwRI are currently trying to improve image quality, but JunoCam should be perfect for the next flyby of Jupiter, which is scheduled to take place in just one month. An further orbit about the same height will be performed by Juno on February 3rd. One of Jupiter’s moons will be scanned by Juno for the very final time at that point. Jupiter itself will be the primary focus of the remaining portion of the extended mission, which is scheduled to bring it to a close in September of 2025.