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When scientists recently pored over archival images of the surface of Venus, they discovered something new: evidence of volcanic activity on Earth’s “twin.”
NASA’s Magellan spacecraft captured these images in the early 1990s as it orbited our closest planetary neighbor, which is similar in size and composition to Earth.
A new analysis of an orbiter’s view of the region near the equator of Venus has revealed a volcanic vent that changed shape and greatly increased in size over the course of eight months.
According to the researchers, the images of the vents represent the first direct geological evidence of recent volcanic activity on the surface of Venus.A study detailing the findings was published Wednesday in the journal scienceand presented at the 54th Lunar and Planetary Science Conference in The Woodlands, Texas.
The Magellan mission became the first mission to photograph the entire surface of Venus before the spacecraft deliberately entered Venus’ hot, toxic atmosphere in 1994 to collect a final set of data.But within a decade, a slew of new missions will head to Venus, including VERITAS CorporationVenus emissivity, radio science, InSAR, topography and spectroscopy missions.
The orbiter will use its instruments to uncover the secrets behind why a planet similar to Earth’s size is covered in volcanic plains and topped with an inhospitable atmosphere.
“NASA’s selection of the VERITAS mission inspired me to look for recent volcanic activity in the Magellan data,” lead study author Robert Herrick, a research professor at the University of Alaska Fairbanks and a member of the VERITAS science team, said in a statement. said in.
“I really didn’t expect to be successful, but after about 200 hours of manually comparing images from different Magellanic orbits, I came across two images of the same area eight months apart showing clear geological changes caused by the eruption .”
Herrick discovered variations in images of the Atla Regio, a vast plateau region that hosts two of the largest volcanoes on Venus, called Ozza Mons and Maat Mons. Both are similar to Earth’s largest volcanoes, but because of their lower slopes, Venus’ two volcanoes are more widespread, Herrick said.
He noticed that between February and October 1991, the caldera on the north side of the dome volcano at Maat Mons changed.
Images of the vent, taken by Magellan in February, show a circular vent measuring less than 1 square mile (2.2 square kilometers) with a steep inner wall and a lava outflow area on the slope.
Eight months later, another image was taken by the spacecraft, showing a very different vent that looked misshapen, nearly double in size and nearly filled to the brim with a lake of lava.
While the difference sounds obvious, both images were taken from opposite angles and perspectives, and at a much lower resolution than images captured by cameras on spacecraft today.
Herrick teamed up with VERITAS project scientist Scott Hensley at NASA’s Jet Propulsion Laboratory in Pasadena, California, to create computer models of the vents to determine what might be causing these changes.
“Only a few simulations match the images, and the most likely scenario is that there was volcanic activity on the surface of Venus during the Magellan mission,” Hensley said. “While this is only one data point for the entire planet, it confirms the presence of modern geological activity.”
Researchers believe that the lava flow Magellan witnessed in 1991 is similar to the lava flow released by the 2018 eruption of Kilauea in Hawaii.
“It’s a needle-in-a-haystack search, and there’s no guarantee the needle is there,” Herrick said. , several years, once every 10,000 years or more. All options can be fitted with existing data. Unless we are very lucky, we now know the frequency is every few months or so, similar to the large basalts on Earth Families of intraplate volcanoes, such as Hawaii, the Galapagos Islands, the Canary Islands, etc.”
While earthquakes could trigger the collapse of the caldera walls, the researchers believe such activity could also lead to eruptions.
Volcanoes are like windows into a planet’s interior, allowing scientists to learn more about the factors that affect its ability to be a habitable world. Missions like VERITAS will help scientists better understand Venus, just as Magellan did decades ago.
The new mission will be equipped with radar to create a global 3D map of Venus and capture details about the composition of the planet’s surface, its gravitational field and what happened to Venus in its past.
“Venus is a mysterious world, and Magellan presents many possibilities,” VERITAS deputy principal investigator Jennifer Whitten, assistant professor of earth and environmental sciences at Tulane University in New Orleans, said in a statement. “Now that we’re pretty sure Earth experienced a volcanic eruption only 30 years ago, this is a small preview of the incredible discoveries VERITAS will make.”