When some speedy, massive stars plow through space, they can cause material to stack up in front of them in the same way that water piles up ahead of a ship. Called bow shocks, these dramatic, arc-shaped features in space.
Stars are bursting into life all over this image from ESA’s Herschel space observatory. It depicts the giant molecular cloud a massive billow of gas and dust almost 12 000 light-years away in the southern constellation of Norma, the Carpenter's Square.
Looking northeast over the dark, cratered, informally named Cthulhu Regio toward the bright, smooth, expanse of icy plains informally called Sputnik Planum. The entire expanse of terrain seen in this image is 1 800 km across.