Planetary scientists have examined volcanic areas on Venus that were imaged two or three times by NASA’s Magellan spacecraft and identified a 2.2-km2 volcanic vent that changed shape in the eight months between two radar images.
“Venus is nearly the same size and mass as Earth,” said University of Alaska Fairbanks Geophysical Institute’s Professor Robert Herrick and Dr. Scott Hensley from NASA’s Jet Propulsion Laboratory.
“Compositional constraints are consistent with Venus having an Earth-like abundance of radioactive elements, which release heat that might drive volcanic activity.”
“The number of impact craters on Venus indicates a mean surface age of a few hundred million years.”
“However, many of the craters have morphologies that appear to have been modified by volcanic processes; if so, it could mean the average surface age is only tens of millions of years, as young as Earth’s ocean basins.”
“The vast majority of Earth’s volcanism is associated with crust formation at mid-ocean ridges or volcanic arcs above subduction zones.”
“Venus does not have current plate tectonics. Geodynamic models of Venus that match the geological and geophysical observations disagree on the expected current level of volcanism, producing various predictions that it could be lower than, the same as, or many times higher than the level of hot spot volcanism on Earth.”
“On Earth, the Hawaiian volcanic hot spot erupts every few years,” they added.
“There are several dozen volcanoes on Venus with sizes and gravity signatures indicative of underlying hot mantle plumes larger than Hawaii’s Big Island.”
“It has been predicted that multiple basaltic eruptions might occur over the course of a Venusian sidereal day (243 Earth days).”
“Extending this analogy predicts lava flow areas covering several tens of kilometers over the same period.”
In the research, Professor Herrick and Dr. Hensley examined radar images of Venus’ surface…
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