The space probe flies close to the pizza moon Io and may witness two (!) volcanic eruptions.

For the second time in a short time, the Juno space probe flew by Io, one of Jupiter's moons, last weekend. It again led to countless images. It appears that someone is showing something special.

The image in question clearly shows two – very wide – columns. According to NASA, they are the result of volcanic activity. It is still unclear whether the plumes come from a single giant volcano or from two volcanoes close to each other. This matter is currently being investigated further.

Flight
Juno snapped the photo with the plumes last weekend, when it flew by Io. During this flight, the space probe approached the moon at a distance of about 1,500 kilometers.

Number 2
This was actually Io's second flight in a few months; In December, Juno also made a close flyby of the Moon. This also resulted in great photos, like the one below.

The flybys aim to learn more about volcanic activity on the Moon. In particular, researchers want to know if there is a magma-filled ocean under the moon's surface that feeds volcanoes.

On IU
Io is slightly larger than our Moon, and would therefore be Jupiter's third largest moon. In addition, Io is known to be the most volcanically active celestial body in our solar system; Hundreds of volcanoes can be found on the surface, sometimes producing lava fountains thousands of kilometers high. The fact that the Moon is very volcanically active can be traced back to Jupiter and its two largest moons: Europa and Ganymede. The latter two moons attract Io in such a way that it moves in a somewhat elliptical orbit around Jupiter. As a result, the distance between Jupiter and Io varies greatly. Thus Jupiter also pulls strongly and less strongly on the Moon. It results in a tidal effect. Of course we also know them here on Earth; The moon pulls in seawater, causing it to move in a certain direction and alternating between high and low tides. Something similar happens on Io – due to Jupiter's gravity – as well. Only there is no water there, but only a solid surface. That surface is pulled by Jupiter – when the distance to Io is small – up to 100 meters, and then relaxes again when the distance increases. It's a process that generates a lot of heat and causes the rocks just below the surface to liquefy. Those liquid rocks want to rise, which is why the Moon is volcanically active.

This is not the first time Juno has detected volcanic plumes on Io. A few years ago, it also spotted – quite unexpectedly – a large plume above the Pizza Moon while flying by Jupiter. This column (you can see it below) was immortalized by Jupiter from a distance of about 300,000 km. Thanks to Juno's now flyby of Io, we can see the volcanic plumes from a much closer distance; At the time Juno captured it, the probe was only 2,200 miles (3,800 kilometers) from Io's surface.

Juno has been orbiting Jupiter since 2016. The mission's main goal is to glimpse Jupiter's thick cloud cover and provide more information about how the gas giant is built, formed and evolves. But there has always been a lot of interest in the moons of the gas giant. For example, there have been previous flights of Ganymede and Europa. Io also enjoyed Juno's attention. The latter will remain so for a while; Because in the near future Juno will fly by the Pizza Moon — a title the moon owes to its bright, colorful appearance — several more times. However, the distance to the Moon is increasing; Juno passes Io during the next journey, at a distance of about 16,500 km. But there's still plenty to see and learn from further away, so we'll undoubtedly see and hear more from Io.