First-ever direct evidence of an active volcano on Venus has been discovered.
They examined radar photos captured by the NASA Magellan mission in the 1990s, about three decades ago.
In less than a year, the photos indicated that a volcanic vent on Venus changed form and increased dramatically in size.
Why the discovery of active volcanism on Venus is significant.
Venus, commonly known as Earth’s twin, bears parallels with our planet in terms of its rocky composition and size.
Because of Venus’s dense atmosphere and deadly carbon dioxide-laden clouds, direct observations are difficult.
On Earth, over 1,300 active volcanoes have been detected, but until recently, no evidence of volcanism has been discovered on Venus.
Magellan could chart 43 percent of Venus
The survey of Venus by Magellan was not an easy feat.
The mission regularly orbited Venus and captured several photos of the same spots. The orbit of the spacecraft began to degrade early in the mission, forcing it to map less with each circle around the planet.
Notwithstanding the challenges, the mission managed to map at least twice 43% of Venus.
The photos revealed “unmistakable geological changes resulting from an eruption.”
Robert Herrick, a research professor at the University of Alaska Fairbanks, said, “I didn’t expect to be successful, but after about 200 hours of manually comparing the images of different Magellan orbits, I saw two images of the same region taken eight months apart exhibiting telltale geological changes caused by an eruption.”
A volcanic vent linked with Maat Mons underwent a substantial alteration.
Geological changes were discovered in the Atla Regio region near Venus’ equator, where two of the planet’s greatest volcanoes are located: Ozza Mons and Maat Mons.
The region was thought to be volcanically active, but there were no signs of recent activity.
While studying Magellan data, it was discovered that between February and October 1991, a volcanic vent linked with Maat Mons altered considerably.
In February’s photograph, the volcanic vent seemed nearly round.
In the photograph from February, the vent seemed nearly round and covered an area of less than 2,200 square kilometers. The vent has steep inner sides and evidence of lava draining down its external slopes, both of which are indicative of volcanic activity.
Images taken afterward show that the same vent had warped.
In radar photos captured eight months later, the same vent was twice as large and deformed. It also looked to be completely surrounded by a lava lake.
It was difficult to compare the photographs since the two observations were made from opposite viewing angles and presented distinct views.
In addition, the three-decade-old data’s poor resolution added to the problems.
Change may have been generated only by a volcanic explosion.
The scientists then created computer models of the vent to simulate various geological events, such as landslides.
They determined that only a volcanic eruption could have generated the observed shift in the vents based on these models.
The researchers link the magnitude of the lava flow produced by Maat Mons to the 2018 Kilauea eruption on Hawaii’s Big Island.
NASA and ESA are considering separate Venus expeditions
Volcanoes that are currently active can give information on how the interior of a planet shapes its crust, drives its development, and affects its habitability.
One of NASA’s upcoming Venus missions, VERITAS (Venus Emissivity, Radio science, InSAR, Topography, and Spectroscopy), will do this precise task.
EnVision, which is slated to launch in the early 2030s, is another mission the ESA is preparing for Venus.
What is the purpose of NASA’s VERITAS mission?
VERITAS will utilize synthetic aperture radar to generate global 3D maps and a near-infrared spectrometer to determine Venus’ surface composition.
The spacecraft will measure the planet’s gravitational field in order to establish its internal structure. It will give information on the historical and present geologic processes of the planet.