Last year, astronomers observed two neutron stars collide. A crash in gravitational waves to detectors here on Earth. Represented in sound, you can hear a small upwards sweep in frequency, in the data, if you listen closely. Several seconds later, the first waves of electromagnetic radiation arrived here on Earth – the first time a collision has been detected by both light and gravitational waves. And it’s in studying the electromagnetic of the collision that astrophysicists have gotten a far better of what really happened after those binary neutron stars merged, 130 million light years away. “Oh yeah, absolutely, so it gives us an understanding of all the nitty-gritty of what’s going on after the merger takes place.” Kunal Mooley, an astrophysicist at Caltech. First, he says, the stars collided, creating a massive, black hole_like object, which started sucking up the cloud of neutron-rich cosmic debris left over from the crash. But its was limited. “It cannot eat all of it, so some bit of it basically escapes.” Those escaping leftovers spewed outward into space, as a powerful jet. But along the way, Mooley says, the jet appears to have interacted with that cloud of neutron-rich material, blowing up a sort of cocoon within the debris around the collision. Until finally, the jet burst out and slammed into interstellar space releasing yet more radiation we could detect here on Earth.