Jupiter's moon Io, which is considered to be the most geologically active object in the solar system with more than 400 active volcanoes, was rocked by three massive volcanic eruptions within a two-week period in August last year, NASA announced Monday. The three bright eruptions reportedly followed each other closely surprising scientists who had only expected to see a single huge outburst every year or two.
According to the scientists, Io’s extreme geologic activity is the result of tidal heating caused by friction generated within the moon’s interior as it is pulled between Jupiter and the planet's other Galilean moons, including Europa, Ganymede and Callisto. The latest discovery of three volcanic eruptions on Io led astronomers to speculate that such explosions, which can eject material hundreds of miles above the satellite's surface, might be much more common than previously believed.
“Here we had three extremely bright outbursts, which suggest that if we looked more frequently we might see many more of them on Io,” Imke de Pater, a professor at the University of California, Berkeley, and the lead author of one of two papers describing the eruptions, said in a statement.
Io, the innermost of Jupiter’s four moons, has a diameter of nearly 2,300 miles and is the fourth-largest moon in the solar system. It is the only known place in the solar system -- other than Earth -- with volcanoes erupting extremely hot lava. Because of Io's low gravity, large eruptions throw volcanic material high into space, creating an umbrella of debris.
De Pater discovered the first two eruptions on Aug. 15, 2013 in Io’s southern hemisphere with the brighter one producing a 50-square-mile lava flow while the other eruption produced flows covering 120 square miles.
The third and the largest eruption -- one of the brightest ever seen on Io -- was discovered on Aug. 29, and further analysis helped the astronomers determine that the temperature of the eruption was likely much higher than typical eruption temperatures currently being recorded on Earth.
This extremely high temperature is "indicative of a composition of the magma that on Earth only occurred in our planet’s formative years," de Pater said.
The astronomers have also developed models to predict the volume of magma spewed during an eruption, which is expected to help them “understand the processes that helped shape the surfaces of all the terrestrial planets, including Earth, and the moon.”