What can get the imagination into super-drive more quickly than the crashing of really huge objects?

Like when a Mars-sized planet did a head-on into the Earth and, the scientific consensus says, created the moon. Or when a potentially dinosaur-exterminating asteroid heads towards Earth, or when what are now called “near-Earth objects” seem to be on a collision course. (There actually aren’t any now, as far as I can tell from reports.)

But for scientists, collisions across the galaxies are not so much a doomsday waiting to happen, and have become a significant and growing field of study.

The planet-forming centrality of collisions — those everyday crashes of objects from grain-sized to planet-sized within protoplanetary disks — has been understood for some time; that’s how rocky planets come to be. In today’s era of exoplanets, however, they have taken on new importance: as an avenue into understanding other solar systems, to understanding the composition and atmospheres of exoplanets, and to get some insight into their potential habitability.

Read more at the Many Worlds Blog.