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Using archival data from the Magellan spacecraft that orbited Venus in the early 1990s scientists think they have identified an active vent that appeared to change shape based on radar images taken eight months apart.

From the abstract of their paper:

We examine volcanic areas on Venus that were imaged two or three times by Magellan and identify a ~2.2 km2 volcanic vent that changed shape in the eight months between two radar images. Additional volcanic flows downhill from the vent are visible in the second epoch images, though we cannot rule out that they were present but invisible in the first epoch due to differences in imaging geometry. We interpret these results as ongoing volcanic activity on Venus.

This result is different that other research released last month that used Magellan data to identify geological features on Venus most likely to be active. In today’s results the scientists think they have spotted an actual volcanic eruption, as shown in the two images to the right. The image is taken from Figure 2 of the paper, with the changes in the center bottom vent clearly visible.

There is much uncertainty in these results that must be mentioned. The images are not optical but radar, so the scientists had to do a lot of computer processing to get the final result. They also compared this work with computer simulations to help confirm their conclusions.

The results also leave open the question of the total amount of volcanism presently active on Venus. As the scientists note in their conclusion, “With only one changed feature, we cannot determine how common currently active volcanism is on Venus.”

Nonetheless, the research using both new and archival data in the past thirty years is increasingly telling us that there is some active volcanism on Venus, hidden beneath its thick hellish cloudy atmosphere.