JPL
Careers
Education
Science & Technology
JPL Logo
JPL Logo
Solar System
.

Study Finds Venus’ ‘Squishy’ Outer Shell May Be Resurfacing the Planet

Feb. 23, 2023
Venus volcanoes

This illustration of the large Quetzalpetlatl Corona located in Venus’ southern hemisphere depicts active volcanism and a subduction zone, where the foreground crust plunges into the planet’s interior. A new study suggests coronae reveal locations where active geology is shaping Venus’ surface.

Credit: NASA/JPL-Caltech/Peter Rubin

The research uses archival NASA data to show that Venus may be losing heat from geologic activity in regions called coronae, possibly like early tectonic activity on Earth.

Earth and Venus are rocky planets of about the same size and rock chemistry, so they should be losing their internal heat to space at about the same rate. How Earth loses its heat is well known, but Venus’ heat flow mechanism has been a mystery. A study that uses three-decade-old data from NASA’s Magellan mission has taken a new look at how Venus cools and found that thin regions of the planet’s uppermost layer may provide an answer.

Our planet has a hot core that heats the surrounding mantle, which carries that heat up to Earth’s rigid outer rocky layer, or lithosphere. The heat is then lost to space, cooling the uppermost region of the mantle. This mantle convection drives tectonic processes on the surface, keeping a patchwork of mobile plates in motion. Venus doesn’t have tectonic plates, so how the planet loses its heat and what processes shape its surface have been long-running questions in planetary science.

The study looks at the mystery using observations the Magellan spacecraft made in the early 1990s of quasi-circular geological features on Venus called coronae. Making new measurements of coronae visible in the Magellan images, the researchers concluded that coronae tend to be located where the planet’s lithosphere is at its thinnest and most active.

This composite image was created by inserting approximately 70 orbits of NASA's Magellan data into an image obtained at the Arecibo, Puerto Rico radiotelescope and shows a geologically complex region in the southern hemisphere of Venus.

This composite radar image of Quetzalpetlatl Corona was created by overlaying data from about 70 orbits of NASA’s Magellan mission into an image obtained by the Arecibo Observatory radio telescope in Puerto Rico. The rim of the corona indicates possible tectonic activity.

Credit: NASA/JPL
Full Image Details
This radar image from NASA's Magellan spacecraft shows a region located in a vast plain to the south of Aphrodite Terra. The data for this image was obtained in January 1991.

This radar image from NASA’s Magellan mission shows circular fracture patterns surrounding the “Aine” corona, located in Venus’ southern hemisphere. The corona is about 124 miles (200 kilometers) across and shows various features that may be associated with volcanic activity.

Credit: NASA/JPL
Full Image Details

“For so long we’ve been locked into this idea that Venus’ lithosphere is stagnant and thick, but our view is now evolving,” said Suzanne Smrekar, senior research scientist at NASA’s Jet Propulsion Laboratory in Southern California, who led the study published in Nature Geoscience.

Just as a thin bedsheet releases more body heat than a thick comforter, a thin lithosphere allows more heat to escape from the planet’s interior via buoyant plumes of molten rock rising to the outer layer. Typically, where there’s enhanced heat flow, there’s increased volcanic activity below the surface. So coronae likely reveal locations where active geology is shaping Venus’ surface today.

The researchers focused on 65 previously unstudied coronae that are up to a few hundred miles across. To calculate the thickness of the lithosphere surrounding them, they measured the depth of the trenches and ridges around each corona. What they found is that ridges are spaced more closely together in areas where the lithosphere is more flexible, or elastic. By applying a computer model of how an elastic lithosphere bends, they determined that, on average, the lithosphere around each corona is about 7 miles (11 kilometers) thick – much thinner than previous studies suggest. These regions have an estimated heat flow that is greater than Earth’s average, suggesting that coronae are geologically active.

Get the Latest JPL News

SUBSCRIBE TO THE NEWSLETTER

“While Venus doesn’t have Earth-style tectonics, these regions of thin lithosphere appear to be allowing significant amounts of heat to escape, similar to areas where new tectonic plates form on Earth’s seafloor,” said Smrekar.

A Window Into Earth’s Past

To calculate how old a celestial body’s surface material is, planetary scientists count the number of visible impact craters. For a tectonically active planet like Earth, impact craters are erased by the subduction of continental plates and covered by molten rock from volcanoes. If Venus lacks tectonic activity and the regular churn of Earth-like geology, it should be covered in old craters. But by counting the number of Venusian craters, scientists estimate that the surface is relatively young.

Recent studies suggest the youthful appearance of Venus’ surface is likely due to volcanic activity, which drives regional resurfacing today. This finding is supported by the new research indicating higher heat flow in coronae regions – a state that Earth’s lithosphere may have resembled in the past.

“What’s interesting is that Venus provides a window into the past to help us better understand how Earth may have looked over 2.5 billion years ago. It’s in a state that is predicted to occur before a planet forms tectonic plates,” said Smrekar, who is also the principal investigator of NASA’s forthcoming Venus Emissivity, Radio science, InSAR, Topography, And Spectroscopy (VERITAS) mission.

VERITAS will pick up where Magellan left off, improving upon that mission’s data, which is low resolution and comes with large margins of error. Targeting launch within a decade, the mission will use a state-of-the-art synthetic aperture radar to create 3D global maps and a near-infrared spectrometer to figure out what the surface is made of. VERITAS will also measure the planet’s gravitational field to determine the structure of Venus’ interior. The instruments will together fill in the story of the planet’s past and present geologic processes.

“VERITAS will be an orbiting geologist, able to pinpoint where these active areas are, and better resolve local variations in lithospheric thickness. We’ll be even be able to catch the lithosphere in the act of deforming,” said Smrekar. “We’ll determine if volcanism really is making the lithosphere ‘squishy’ enough to lose as much heat as Earth, or if Venus has more mysteries in store.”

News Media Contact

Ian J. O’Neill

Jet Propulsion Laboratory, Pasadena, Calif.

818-354-2649

ian.j.oneill@jpl.nasa.gov

2023-024

Related News

Solar System .

NASA’s Magellan Data Reveals Volcanic Activity on Venus

Mars .

Engineers Keep an Eye on Fuel Supply of NASA’s Oldest Mars Orbiter

Solar System .

Study Finds Ocean Currents May Affect Rotation of Europa’s Icy Crust

Solar System .

NASA’s NuSTAR Telescope Reveals Hidden Light Shows on the Sun

Mars .

NASA’s Perseverance Rover Completes Mars Sample Depot

Solar System .

NASA’s Juno Team Assessing Camera After 48th Flyby of Jupiter

Solar System .

NASA’s Psyche Mission Continues Preparation for Launch in 2023

Solar System .

NASA’s Lunar Flashlight Team Assessing Spacecraft’s Propulsion System

Mars .

NASA Explores a Winter Wonderland on Mars

Solar System .

Juno Spacecraft Recovering Memory After 47th Flyby of Jupiter

Explore More

Mission .

Lunar Trailblazer

Image .

Radar Observations of Elongated Near-Earth Asteroid 2011 AG5

Image .

Three-Telescope View of the Sun

Mission .

Cooperative Autonomous Distributed Robotic Exploration

Image .

NASA's Psyche: Picking up Launch Prep for 2023

Event Feb. 16, 2023 .

Perseverance: Two Years on Mars

Mission .

Ranger 1

Image .

Lunar Flashlight's Trajectory Correction Maneuver (Illustration)

Image .

NASA's Lunar Flashlight Spotted From Earth on Its Way to the Moon

Image .

NEO Surveyor in an Infrared Starfield Filled With Asteroids (Illustration)

About JPL
Who We Are
Executive Council
Directors
Careers
Internships
The JPL Story
JPL Achievements
Documentary Series
Annual Reports
Missions
Current
Past
Future
All
News
All
Earth
Solar System
Stars and Galaxies
Subscribe to JPL News
Galleries
Images
Videos
Audio
Podcasts
Apps
Visions of the Future
Slice of History
Robotics at JPL
Events
Lecture Series
Team Competitions
Speakers Bureau
Calendar
Visit
Public Tours
Virtual Tour
Directions and Maps
Topics
JPL Life
Solar System
Mars
Earth
Climate Change
Exoplanets
Stars and Galaxies
Robotics
More
Asteroid Watch
NASA's Eyes Visualizations
Universe - Internal Newsletter
Social Media
Get the Latest from JPL
Follow Us

JPL is a federally funded research and development center managed for NASA by Caltech.

More from JPL
Careers Education Science & Technology Acquisitions JPL Store
Careers
Education
Science & Technology
Acquisitions
JPL Store
Related NASA Sites
Basics of Spaceflight
Climate Kids
Earth / Global Climate Change
Exoplanet Exploration
Mars Exploration
Solar System Exploration
Space Place
NASA's Eyes Visualization Project
Voyager Interstellar Mission
NASA
Caltech
Privacy
Image Policy
FAQ
Feedback
Site Managers: Veronica McGregor, Randal Jackson
Site Editors: Tony Greicius, Naomi Hartono
CL#: 21-0018