Researchers managed to perform the most detailed analysis of a lava lake on Io, one of Jupiter’s moons. Dubbed Loki Patera, the lake occupies a surface of 8,300 square miles and measures 127 miles from one end to the other. The analysis was organized in a study published in the journal Nature.
Io displays an interesting volcanic activity
Io is the cosmic body with the most intense volcanic activity in the Solar System. Because of the gravitational pull issued by Jupiter and its other larger moons, Io’s interior gets a constant source of tidal heat. This is what causes the moon to be ‘filled’ with lava.
Therefore, Io’s surface is dotted with both temporary eruptions and stable lava lakes, such as Loki Patera. By using advanced telescopes which measure infrared light, researchers were able to measure the temperature of the lake. They noticed how it fluctuated, turning higher once every 500 days. Europa, another one of Jupiter’s moons, helped them find an explanation for this.
Europa’s occultation helped researchers identify the source of the peculiar behavior of the lava
On March 8th, 2015, Europa performed an occultation, and passed between Earth and Io’s lava lake. Therefore, the infrared light which telescopes were measuring was blocked. This allowed them to record the temperature coming only from the extremities. The lava had a higher temperature in the southeast, and a lower one in the northwest.
It seems that the lava on top sometimes forms a crust which cools down. After it is completely cooled, it sinks at the bottom of the lake, and hot incandescent lava takes its place at the top. Therefore, these measurements can not only tell the temperature of the lava, but also how old it is.
Researchers found this behavior fascinating. Besides finding more about the composition of Jupiter’s moon, they can also understand how the volcanic activity of Earth had developed millions of years ago. Europa’s next occultation of Io occurs in 2021, when researchers want to perform more thorough analyses.
Image Source: Wikimedia Commons