Turns out Venus is even weirder than we thought!
Using data that's three decades old, NASA scientists say they've figured out what happens to Venus' heat when it's lost to space — and discovered that the planet's surface may be "squishy" enough for it to be hemorrhaging its internal warmth.
As NASA's Jet Propulsion Laboratory noted in a post about the new findings published in the journal Nature Geoscience, this Venusian discovery stems from astronomers trying to understand the planet's surface, which unlike Earth does not have tectonic plates to explain where its heat goes.
Our planet's heat loss from its hot core is intimately tied to its tectonic plates. But because Venus demonstrably loses heat much the same way Earth does but lacks tectonic plates, planetary scientists have long questioned what exactly is causing it to lose its heat.
Looking at data from NASA's Magellan mission to Venus in the early 1990s, the JPL researchers took a closer look at dozens of previously unstudied coronae, or "quasi-circular geological features," when trying to figure out what's going on with the planet named for the Roman goddess of love — and found that those coronae tend to be where its lithosphere is thinnest, which would denote volcanic activity underneath.
"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," the JPL blog post notes with terrific metaphorical aplomb.
A study using data from @NASA's Magellan mission has found that Venus' 'squishy' outer shell may be resurfacing the planet. This new information could help us better understand how Earth's tectonics began over 2.5 billion years ago! https://t.co/vjmCa4ZgIB pic.twitter.com/kkjThR2RGt
— NASA JPL (@NASAJPL) February 23, 2023
Clean Your Plate
Of the 65 understudied coronae NASA looked at, some were hundreds of miles across.
"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," Suzanne Smrekar, a senior JPL research scientist who co-wrote the Nature Geoscience paper, said in the update.
With all these findings just from archival data, Smrekar and her team have high hopes for the forthcoming Venus Emissivity, Radio science, InSAR, Topography, And Spectroscopy (VERITAS) mission that will take an even closer look at the planet that is as hot and rocky as its namesake.
With VERITAS, the scientist said, scientists will be able to "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."
More on strange planets: Scientists Find Gigantic Planet a Quarter the Size of Its Star