The hellscape of Venus is riddled with even more volcanoes than scientists thought.
Using radar images taken by NASA’s Magellan spacecraft in the 1990s, researchers cataloged about 85,000 volcanoes strewn across the Venusian surface. That’s nearly 50 times as many volcanoes as past surveys counted. Planetary scientists Rebecca Hahn and Paul Byrne of Washington University in St. Louis debuted the map in the April JGR Planets.
Such a thorough inventory of volcanism on Venus could offer clues about the planet’s interior, such as hot spots of magma production, Byrne says. And with the recent discovery that Venus is volcanically active, the map could also help pinpoint places to look for new eruptions (SN: 3/15/23).
Almost all the volcanoes that Hahn and Byrne found are less than 5 kilometers wide. About 700 are 5 to 100 kilometers across, and about 100 are wider than 100 kilometers. The team also found many tight clusters of small volcanoes called volcanic fields.
Literal hot spots
This map of Venus shows the locations and sizes of all volcanoes visible in radar data from the Magellan spacecraft. The newfound volcanoes range in size from less than 5 kilometers wide to more than 100 kilometers across, though most are on the small side. Continents and other geographic regions are shown in gray.
Mapping Venus’ volcanoes
“We have a better handle of how many volcanoes are on Venus than are on Earth,” where most volcanoes are probably hidden beneath the oceans, Byrne says. But he doesn’t think the Magellan data tell the whole story of Venus’ volcanism. That spacecraft could see features as small as about 1 kilometer in diameter. Earth has “lots and lots of volcanoes that are far smaller than a kilometer across,” Byrne says. “That’s probably the case with Venus, too.”
We may soon find out. NASA’s VERITAS spacecraft and the European Space Agency’s EnVision mission are slated to turn their much sharper eyes on Venus’ infernal surface within the next decade or so (SN: 6/2/21).