Pictures from radio telescopes have shown how volcanic activity affects the atmosphere of Jupiter’s moon Io.
Io is the most volcanically active moon in our solar system. It is home to over 400 active volcanoes that spew sulfur gases that, when frozen on the surface, give Io its yellow-white-orange-red color. Io has an atmosphere that can tell us about its volcanic activity and explain what is happening inside the moon.
Previously, scientists received images of the satellite in direct sunlight, as well as during its passage in the shadow of Jupiter. To distinguish between the different processes causing Io’s atmosphere, a team of astronomers used ALMA to take pictures of the moon as it entered and exited Jupiter’s shadow.
Thanks to the resolution and sensitivity of ALMA, researchers were able to view the plumes of sulfur dioxide (SO2) and sulfur monoxide (SO). Based on the imagery, they estimate that active volcanoes produce about 30-50% of Io’s atmosphere.
In some plumes, neither SO nor SO2 was found: they consist mainly of potassium chloride. According to the researchers, this suggests that the different volcanoes of Io are powered by magma reservoirs of different composition.