sciencehabit shares a report from Science Magazine: Choked by a smog of sulfuric acid and scorched by temperatures hot enough to melt lead, the surface of Venus is sure to be lifeless. For decades, researchers also thought the planet itself was dead, capped by a thick, stagnant lid of crust and unaltered by active rifts or volcanoes. But hints of volcanism have mounted recently, and now comes the best one yet: direct evidence for an eruption. Geologically, at least, Venus is alive.
The discovery comes from NASA’s Magellan spacecraft, which orbited Venus some 30 years ago and used radar to peer through the thick clouds. Images made 8 months apart show a volcano’s circular mouth, or caldera, growing dramatically in a sudden collapse. On Earth, such collapses occur when magma that had supported the caldera vents or drains away, as happened during a 2018 eruption at Hawaii’s Kilauea volcano. Witnessing this unrest during the short observation period suggests either Magellan was spectacularly lucky, or, like Earth, Venus has many volcanoes spouting off regularly, says Robert Herrick, a planetary scientist at the University of Alaska, Fairbanks. Herrick, who led the study, says, “We can rule out that it’s a dying planet.”
The discovery, published today in Science and presented at the Lunar and Planetary Science Conference, makes Venus only the third planetary body in the Solar System with active magma volcanoes, joining Earth and Io, Jupiter’s fiery moon. It means future missions to Venus will be able to study “bare, gorgeous new rock” that provides a sample of the planet’s interior, Gilmore says. The discovery of more volcanoes, in old or future data, will also help scientists understand how Venus is shedding its interior heat and evolving. And it will shake scientists out of their long-standing view that a spasm of activity a half-billion years ago repaved the planet’s surface — as evidenced by a relative paucity of impact craters — and was followed by a long period of quiet.