Researchers have identified evidence they interpret as active volcanism on the surface of Venus, according to a new analysis of radar images from the Magellan spacecraft. The images reveal a vent that changed shape on Venus, which they believe points to ongoing volcanic activity there. Many volcanoes have been identified on the surface of Venus, but evidence of recent volcanic activity on the planet has been lacking. As a result, it was unknown whether the prominent volcanic features of Venus' geologically young surface are a product of ongoing active volcanism or relics of ancient volcanic activity that has since ceased. Although no volcano has been observed erupting on Venus, some previous research has suggested that ongoing volcanic activity might occur in various regions across the planet's surface. However, geodynamic models of the planet produce different predictions for the current level of Venusian volcanism. Robert Herrick and Scott Hensley have examined radar images of Venus' surface collected by the Magellan spacecraft between 1990 and 1992, searching them for evidence of Venusian volcanic activity. During its mission, Magellan used radar to image the surface of Venus from different orbits, observing some locations two or three times over the course of two years, including areas later identified as potential locations for volcanic activity. Because the data were not conducive to automated methods, Herrick and Hensley manually searched full-resolution radar images of these areas for changes in geologic features that occurred between Magellan's radar imaging cycles. The authors identified a volcanic vent – part of the larger Maat Mons volcano system – which appeared to grow larger and change shape between two Magellan radar images taken eight months apart. Changes to the adjacent surface could possibly have been caused by a lava flow emanating from the vent. Herrick and Hensley interpret the observed changes as indicating ongoing volcanic activity on Venus.
Special Embargo Note: The embargo on this study will lift at 2:00pm US ET, Wednesday, 15 March, at the start of a related briefing at the 54th Lunar Planetary Science Conference. This briefing will be streamed live on the LPSC Livestream page.
