Counting craters: A close-up of the terraced structure within a crater taken by the Japanese SELENE probe.
Credit: SELENE/JAXA
Haruyama said their results were surprising because most research done on the near side of the Moon has dated the last burst of volcanism at three billion years.
"So in that sense it was surprising to find the younger volcanism on the farside," he told Cosmos Online. Before this study, the data on the other side of the Moon was limited, he said, meaning that only craters of 100 m or more had been mapped.
Ice deposits
The younger mare deposits on the farside were widespread, with some at the south pole and some in the central region. The researchers said that they are yet to understand what caused the later eruptions.
Haruyama and colleagues also used the satellite's images to check for ice in permanently-shadowed sections of farside craters, lit only by scattered light reflected from the crater walls.
That study, published in Science last week ruled out any exposed ice, but Haruyama said there might still be ice present that appears dark because it's mixed up with lunar soil.
