Venus' Mysterious Crown-Shaped Formations Reveal Clues to Planet's Interior

Across the scorched face of Venus, 741 massive circular scars — called coronae — have long puzzled those who study the inner lives of planets. Now, a team led by planetary scientist Anna Gulcher has used decades-old radar echoes from NASA's Magellan spacecraft to build three-dimensional portraits of these formations, finding in them the fingerprints of a restless mantle and the absence of the one geological gift that made Earth livable. The work is less a story about Venus than a meditation on contingency — on how the presence of oceans, and the plate tectonics they enable, may be the slender