Ina Caldera, the Moon
Over the last week, we saw Nature Geosciences article come out that, according to the news, either says that we might expect future volcanism on the Moon or there is little-to-no chance of modern volcanism on our nearest neighbor. The study, which used X-rays to examine the interior state of the Moon through artificial rocks of lunar composition, suggests that molten magma likely lurks at depth in the Moon, but the density of that magma might make an eruption highly unlikely. However, if the magma cools and differentiates (changes composition due to removal of crystals), then the magma could rise and erupt. People across the centuries have claimed to have seen volcanic eruptions on the Moon, but likely they were actually meteor impacts rather than an eruption. Ina Caldera (above) is one of the many volcanic features on the Moon and appears to be a collapse feature, suggesting potential caldera volcanism in the lunar past.
Image: Ina Caldera on the Moon imaged by the LRO / NASA