Jupiter’s moon Io holds a massive lava lake within one of its craters. Scientists have found huge waves of molten material sloshing about in Io’s lava reservoir.
Phys.Org reports that Io is the most volcanically active space body in the solar system. Scientists collected data on Io’s heat output when another of Jupiter’s moons, Europa, was in a key relative position for clear observation of Io’s heat signature.
The study found that infrared readings of Io’s activity showed evidence of massive waves passing from west to east over Io’s largest lava lake. Wave movement in the lava-filled crater seems to cover about a kilometer per day.
The lava-filled crater, called Loki Patera, creates a hot spot that is seen to brighten and dim about every 400 to 600 days. The overturning of lava in massive slow waves could explain the changes observed in the hot spot over time. Another explanation is that periodic volcanic eruptions cause the brightenings.
Loki Patera is about 127 miles across and has a molten surface area larger than Lake Ontario.
“If Loki Patera is a sea of lava, it encompasses an area more than a million times that of a typical lava lake on Earth,” Katherine de Kleer of UC Berkeley said. “In this scenario, portions of cool crust sink, exposing the incandescent magma underneath and causing a brightening in the infrared.”
The data was collected using the two 27.6-foot mirrors of the Large Binocular Telescope Observatory in Arizona. The data allowed astronomers to create a thermal map of Loki Patera with a resolution better than 6.25 miles.
“This is the first useful map of the entire patera,” Ashley Davies of the Jet Propulsion Laboratory in Pasadena said. “It shows not one but two resurfacing waves sweeping around the patera. This is much more complex than what was previously thought.”
The study will be published in the journal Nature.