After revisiting 30-year-old data, scientists have discovered evidence of recent volcanic activity on Venus, according to a new paper published Wednesday in the journal Science.
With this new finding, Venus joins the ranks of Earth and Jupiter’s moon Io as the only three planetary bodies in our solar system that have active magma volcanoes.
Researchers already knew that Venus’ surface is dotted with at least hundreds of volcanoes, lava fields, channels carved by lava and other volcanic features. But they weren’t sure whether any of those volcanoes are currently active. To help answer that question, they turned to radar imaging data that NASA’s Magellan spacecraft had captured from 1990 to 1992. Technological advancements over the last 30 years made it possible for the team to analyze the old images in helpful new ways.
They looked closely at volcanic areas on the planet’s surface that Magellan had imaged multiple times. While doing so, they noticed that the shape of one volcanic vent had changed between two radar images dated eight months apart. In the later image, they also spotted what appeared to be lava flowing downhill from the vent, located on the north side of Maat Mons, the highest volcano on Venus.
Together, the spacecraft’s observations suggest volcanic activity on Venus at least as recently as the 1990s, which the researchers consider to be “ongoing.” It’s possible that Magellan simply got lucky with its timing, but researchers say it’s more likely that Venus’ volcanoes are still erupting regularly.
“There’s no way you have a planet that big that was doing something 30 years ago and stopped,” says Paul Byrne, a planetary scientist at Washington University in St. Louis who was not involved in the project, to Science News’ Lisa Grossman. “It’s definitely still active today.”
This new finding builds on past research, including a 2020 study that found what appeared to be 37 active volcanoes on Venus. Earlier projects have also identified abnormally hot regions on the planet’s surface that scientists suspect are million-year-old lava flows that haven’t had time to cool down yet. Researchers have also detected upticks in sulfur dioxide in Venus’ atmosphere, which may have come from recent volcanic activity.
“It is nice to have a visual confirmation of the volcanic activity on Venus,” says Clara Sousa-Silva, an astrochemist at Bard College who was not involved with the new research, to NPR’s Ari Daniel. “But given that this was something we had speculated, it’s not shocking to have this paper come out.”
The findings could offer new insights into Venus’ geological evolution over billions of years, as well as help explain some of its unusual atmospheric properties.
Scientists have long been intrigued by Venus, which is the second-closest planet to the sun and has a surface temperature of 864 degrees Fahrenheit. In 1962, when NASA’s Mariner 2 cruised by, Venus became the first planet to be explored by spacecraft. Then, with Magellan, scientists obtained quality radar imagery of Venus’ surface.
This cloud-covered world continues to spark scientific interest today. NASA has two planned projects that would explore Venus, the VERITAS and DAVINCI+ missions, while the European Space Agency also has one in the works called EnVision.
Venus is so similar to Earth that it’s often referred to as our twin or sister planet. At 7,500 miles in diameter, it’s almost as large as Earth. Venus also has a similar composition to Earth, with a rocky mantle encapsulating an iron core.
Of course, Venus and Earth are also very different. There’s likely no life on the surface of Venus, thanks largely to its thick, toxic atmosphere and hot temperatures. But scientists suspect the planet may have hosted oceans that could have supported life billions of years ago. They aren’t exactly sure why Venus became a “hell planet” and Earth, by comparison, remains a habitable paradise. They’re curious to know if Venus’ inhospitable landscape could someday become Earth’s fate, too.
“Venus is a ‘Rosetta stone’ for reading the record books of climate change, the evolution of habitability and what happens when a planet loses a long period of surface oceans,” said James Garvin, the DAVINCI+ principal investigator, in a June 2021 NASA statement about the mission.