Chang Won Lee

In the dark cloud NGC 6334I-North, 5500 light-years from Earth, the ALMA radio interferometer spotted something unexpected: around a young massive star, a disk of gas and dust is swirling, and inside it are seven dense clumps. Each one could become a star. This is what the birth of a stellar family looks like, and an unusually large one at that.

In the stellar nursery HOPS-288, where three suns are forming, the ALMA telescope revealed two scorching regions around a pair of them. At –170°C, ice on cosmic dust melts, and reactions bubble up in the gas: organic molecules are born — methanol and methyl formate.

In the dark cloud G318.049+00.086, where no star has yet formed, dust and gas have arranged themselves into four long filaments. They converge into a dense central hub, like four rivers emptying into a lake. Gas flows along these filaments toward the center: the flow speed reaches 10–20 kilometers per second per parsec of length.

Inside cold clouds of gas and dust where new stars ignite, astronomers have spotted unexpectedly delicate structures. The ALMA telescope, working in the millimeter range, has revealed more than 323 ultra-thin dust filaments within 121 massive clumps.

In a dense cloud of gas and dust where giant stars are born, the ALMA telescope has spotted something familiar. Four thin gas jets shoot out from the same region, each leaving behind a chain of bright knots, like a dashed line.