Mars has sand dunes, as Earth does. But now, NASA’s Odyssey orbiter has revealed something odd: a large dune field shaped roughly like a hexagon. The finding is expected to provide more clues as to how dunes form in Martian winds.

The Hayabusa2 spacecraft touched down briefly and successfully on asteroid Ryugu Friday morning, 200 million miles (300 million km) from Earth. It successfully fired a bullet into the asteroid to puff up dust for sample collection.

The Rosetta space mission revealed a comet as 2 icy balls apparently stuck together billions of years ago. Now scientists say the comet’s double-lobed structure guided its evolution.

The Chinese spacecraft Chang’e-4 made history earlier this year, when it became the first earthly spacecraft to land on the moon’s far side. Now astronomers have named its landing site.