Scientists have a pretty good idea of how single stars live and die. Stars like our sun will grow into behemoths called red giants before they shed their outer layers and become an ethereal planetary nebula. Larger stars — those with more than about eight solar masses — will explode as supernovas. And, theoretically, any star at least 25 times bigger than the sun will end its life as a black hole.
But most stars in the Milky Way are actually binaries or multiples, part of a set. What happens to these stars when they die? Understanding stellar pairs, and how one’s individual development affects the other, is fundamental to understanding stellar evolution as a whole. We’ve only barely started to do that.
“Binary evolution is more complicated than single star evolution,” says LIGO scientist Jolien Creighton of the University of Wisconsin-Milwaukee. “There’s a lot more processes that can happen.” By cataloging their stellar corpses using LIGO, astronomers can learn more about how these stars lived out their lives.
After its initial findings, LIGO took a break for upgrades before firing back up again in fall. As more gravitational wave detections stream in, from LIGO and its upcoming ground- and space-based brethren, astronomers will get a better picture of this invisible cosmos that Einstein saw so clearly.