Uncovering the Mystery of Venus’ Heat Flow with Coronae

NASA researchers have found that thin regions of Venus' lithosphere may hold the key to understanding how the planet cools and what processes shape its surface.^[0] Data from the Magellan probe in the early 1990s, which studied quasi-circular geological features called coronae, shows that these structures tend to occur where the lithosphere is weakest and most active.^[0]

The team made new measurements of the coronae and determined that, on average, the lithosphere around each corona is about 11 kilometers thick, much thinner than previous studies suggested.^[1] The estimated heat flow in these areas is higher than the norm for Earth, suggesting that the coronae are geologically active.^[1]

“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,” explained Suzanne Smrekar, a senior research scientist at NASA's Jet Propulsion Laboratory in Southern California, who led the study published in Nature Geoscience.^[2] The mechanism by which Earth loses its heat is well-documented, yet the process by which Venus dissipates its heat has remained a mystery.^[2]

Smrekar noted, “For so long we've been locked into this idea that Venus' lithosphere is stagnant and thick, but our view is now evolving.”^[3]

On Earth, the planet's core heats the mantle, which then conveys heat to the outer layer or lithosphere, where it radiates out into space.^[0] This causes the mantle to cool, driving the movement of tectonic plates.^[4] Since Venus lacks tectonic plates, it is believed that the thin lithosphere is allowing more heat to escape from the planet's interior, resulting in increased volcanic activity below the surface.^[0]

In conclusion, the research suggests that coronae are likely revealing locations where active geology is shaping Venus’ surface. The findings also provide a window into the past to help us better understand how Earth may have looked over 2.5 billion years ago.^[5]

0. “Venus' squishy surface shows signs of geothermal activity | Science-Environment” Devdiscourse, 24 Feb. 2023, https://www.devdiscourse.com/article/science-environment/2361754-venus-squishy-surface-shows-signs-of-geothermal-activity

1. “Outer shell of Venus may be resurfacing the planet, NASA says” Fox News, 24 Feb. 2023, https://www.foxnews.com/science/outer-shell-venus-resurfacing-planet-nasa-says

2. “Study finds the ‘squishy' outer shell of Venus may be resurfacing the planet” Phys.org, 23 Feb. 2023, https://phys.org/visualstories/2023-02-squishy-outer-shell-venus-resurfacing.amp

3. “Study sheds light on the mysterious happenings on Venus's surface” NewsBytes, 24 Feb. 2023, https://www.newsbytesapp.com/news/science/new-study-sheds-light-on-venus-heat-flow-process/story

4. “Venus’s squishy surface shows signs of geothermal activity” Tech Explorist, 24 Feb. 2023, https://www.techexplorist.com/venuss-squishy-surface-shows-signs-geothermal-activity/57122

5. “New study offers insight into how Venus cools” UPI News, 24 Feb. 2023, https://www.upi.com/Science_News/2023/02/24/nasa-venus-cooling-coronae/7571677249334