To call Venus a true freak planet would be a bit of an understatement. It’s very Earth-like – and yet not as Earth-like as you’d expect from an Earth-like planet. One of these differences is the lithosphere of Venus, the hard outer shell of the planet. On Earth, the lithosphere is fragmented and mobile, split into tectonic plates that help shape the planet’s surface while allowing heat from the planet’s interior to circulate around its jagged edges.

Venus’ lithosphere, on the other hand, is flawless, which makes the cooling and recovery mechanisms of the planet’s surface somewhat mysterious. A new study suggests that Venus may actually have a relatively “soft” lithosphere that regularly returns to the surface. 475 degrees Celsius (887 degrees Fahrenheit). Landers sent there did not last long.

But data collected by the Magellan orbiter decades ago may have kept Venus’ secrets alive all these years. A spacecraft has used radar to penetrate the planet’s thick clouds and image the surface – and now scientists have used the data to reveal that Venus’ lithosphere may be thinner than previously thought.

A research team led by planetary geophysicist Suzanne Smrekar of NASA’s Jet Propulsion Laboratory used Magellan’s data to closely examine volcanic surface features called coronas, as well as the trenches and ridges that surround them. They found that where the ridges are closer together, the lithosphere is likely quite thin and flexible, averaging about 11 kilometers (7 miles).

The simulation shows that in these places the heat flux through the surface is higher than the average heat flux on Earth.

“For a long time we were locked into the idea that Venus’ lithosphere was stagnant and thick, but now our view is changing,” explains Smrekar. “Although Venus does not have terrestrial tectonics, these regions of the thin lithosphere seem to allow significant heat removal, similar to regions where new tectonic plates form on Earth’s seafloor.”

For a long time, scientists believed there wasn’t much on Venus right now, but recent research is increasingly showing the opposite. Crowns are one such clue. These features are somewhat similar to impact craters and consist of a raised ring (like a crown) around a submerged center with concentric faults spreading outward. They can also be huge, hundreds of kilometers across.