Venus has more volcanism than previously known

Venus appears to be more volcanically active than previously known, according to scientists whose new analysis of decades-old radar images has spotted evidence of eruptions at two additional sites on the surface of Earth's inhospitable planetary neighbor.

Radar images obtained by Nasa's Magellan spacecraft from 1990 to 1992 indicated large lava flows at these two locations in the Venusian northern hemisphere at the time of the observations, the researchers said. These findings, coupled with previous studies, indicate that the planet's volcanic activity is comparable to Earth's, they added.

Magellan mapped 98 percent of the Venusian surface. Advances in computing capability have made analysing Magellan's radar data easier in recent years.

"These findings significantly change our understanding of the degree to which Venus is volcanically active, suggesting it could be much more active than previously thought," said planetary scientist Davide Sulcanese of d'Annunzio University in Pescara, Italy, lead author of the study published this week in the journal Nature Astronomy.  One of the two sites is a volcano called Sif Mons, which is about 200 miles wide and situated in a region called Eistla Regio. The before-and-after radar images indicate a lava flow amounting to about 12 square miles of rock. The other site is a large volcanic plain in a region called Niobe Planitia. About 17 square miles of rock was produced in this lava flow.