AYESHA RASCOE, HOST:
In Greek and Roman mythology, Venus is the goddess of love and beauty. But the planet Venus is, well, a hellscape. Thinking crushing pressures, a toxic atmosphere, surface temperatures hot enough to melt lead. The forces that shape the planet, which is in some ways similar to our own, have largely remained a mystery. And now new research offers a new volcanic insight. Science reporter Ari Daniel has more.
ARI DANIEL, BYLINE: Despite all its hostility, Venus, our nearest planetary neighbor, is pretty similar to Earth, so much so that University of Alaska Fairbanks planetary scientist Robert Herrick calls it our true sibling in the solar system.
ROBERT HERRICK: Aside from Earth, it's the only one that has sort of true mountain ranges and huge variety of volcanic features.
DANIEL: Features like lava fields, canals carved by molten rock and hundreds, if not thousands, of volcanoes. So it's clear that Venus is volcanically active, but it's not clear exactly how active.
HERRICK: The time between eruptions could be months, years or tens of thousands of years.
DANIEL: Herrick set out to try to narrow down that time window by searching for evidence of recent volcanic activity. He pored over radar surface imagery collected by the Magellan spacecraft in the early '90s.
HERRICK: It's a needle-in-a-haystack search without any guarantee that there's a needle, right?
DANIEL: He focused his search around the highest volcano on Venus, Maat Mons, named after the Egyptian goddess of truth and justice. And after a couple months of looking, he found something.
HERRICK: So can you see that? You're looking at PowerPoint, hopefully.
DANIEL: Herrick fires up a slide with two side-by-side black-and-white images taken eight months apart of the same spot on the north side of the volcano, each one some 15, 20 miles across. Herrick points out a pockmark. It's a vent, the area where a volcano erupts, discharging its lava, ash and rock. But the shape of that vent differs between the two images.
HERRICK: The outline has changed, and the thing's actually gotten larger and looks shallower as well.
DANIEL: That is, sometime during 1991, Herrick speculates the volcano erupted, forming a lava lake within the vent.
HERRICK: Of course, I could have been very lucky and seen the only thing that happened in the last million years on Venus. But I think the reasonable interpretation suggests that Venus is relatively Earth-like in the frequency of volcanic eruptions.
DANIEL: Around places like Hawaii and Iceland. Herrick and his colleague published their findings in the journal Science. They hope it'll help researchers understand how Venus has evolved geologically over the last 4 1/2 billion years and where it might be headed.
CLARA SOUSA-SILVA: It is nice to have a visual confirmation of the volcanic activity on Venus, but given that this was something we had speculated, it's not shocking to have this paper come out.
DANIEL: Clara Sousa-Silva is a quantum astrochemist at Bard College and wasn't involved in the research. Still, she says this confirmation helps us understand what to expect in Venus's atmosphere.
SOUSA-SILVA: A planet that has a lot of volcanic activity has access to these extreme pressures and temperatures below the surface that can produce molecules that are really unusual and otherwise really hard to make.
DANIEL: NASA's currently got two missions to Venus in the works, missions that will now be informed by these new findings.
HERRICK: We don't just think it's an active planet. We know it's an active planet right now.
DANIEL: Herrick's working to develop an instrument for those upcoming missions to monitor volcanic activity on Venus. He's pretty confident now it'll see something once it's deployed. It just has to survive the infernal planet long enough to make its measurements.
For NPR News, I'm Ari Daniel. Transcript provided by NPR, Copyright NPR.
