Collisions between planets, planetesimals and other objects are common in the galaxies and essential for planet formation. Researchers are focusing on these collisions for clues about which exoplanets have greater or lesser potential habitability. (NASA)
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” seems 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, but rather an essential commonplace and a significant and growing field of study.
The planet-forming centrality of collisions — those every-day 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 ...