To find out, the researchers used the ALMA telescope in Chile – which, incidentally, is surrounded by volcanoes – to measure sulfur isotopes on Io.
The researchers found that between 94-96 percent of the sulfur isotopes released into the atmosphere by volcanic eruptions are lost to space.
It is a finding that, according to the researchers behind the study, shows that the volcanic activity has been going on for as long as Io has existed, that is, about 4.5 billion years.
“The solar system formed with a ratio of 23 sulfur-32 atoms for every sulfur-34 atom. If Io had been unchanged since its formation, the ratio would be the same today. We have shown that Io has lost enormous amounts of sulfur, which means that it has been volcanically active for several billion years,” the Caltech researchers write in a press release.
