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Scientists just recorded a huge eruption on one of Jupiter’s moons

What else can we expect from Io?

NASA/JPL/University of Arizona

NASA/JPL/University of Arizona

While Jupiter’s moon Europa is suspected to host a hidden ocean — boosting the possibility of alien lifeforms — its sibling Io has a reputation for being a lot more destructive.


Hundreds of volcanoes continuously erupt over Io’s surface, thanks to the gravitational tug-of-war between Jupiter and its other moons.

Some blasts are so powerful that they can be seen from telescopes on Earth.

Recently, a huge eruption happened on Io — one of the largest recorded in several years.

Jeff Morgenthaler, senior scientist at the Planetary Science Institute, detected the event with the IoIO observatory.

IoIO dims the blinding light from Jupiter so that the planet’s moons are more visible around it.

That helps it detect slight changes in gas levels around Io.

Jeff Morgenthaler, PSI

Jeff Morgenthaler, PSI

Starting sometime between July and September 2022, levels of sodium and ionized sulfur drastically increased around Io, and stayed high until December.

NASA/JPL/University of Arizona

Spiked levels of these compounds indicate elevated volcanic activity.

The fall 2022 outburst was the largest ever recorded by IoIO, since it began watching Jupiter’s moon in 2017.

It’s unclear if this eruption was any different than others on Io, given its strength.

NASA's Goddard Space Flight Center//Johns Hopkins University Applied Physics


But NASA’s Juno spacecraft, which is currently orbiting Jupiter in order to study the planet and its moons, could shed some light on the mystery.


“Juno measurements may be able to tell us if this volcanic outburst had a different composition than previous ones.”

NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute

The spacecraft flew by Europa during the outburst, and also passed Io in December 2022, collecting more data and images of the strange world. It will encounter Io again in December 2023.

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