A Gluttonous Black Hole: Five Years of Watching GX 339-4's Outbursts
A black hole is an insatiable cook, and the star beside it is a pot of boiling soup. The cook ladles out the soup, but some spills: similarly, GX 339-4 pulls in gas from its neighboring star, but it doesn't hold onto all of it. The excess matter shoots out from the black hole's poles in two narrow jets, like splashes from an overfilled pot.