In a new article in The Astrophysical Journal, Ryan Lau and company share new observations of a massive young star called a Wolf-Rayet star that is in orbit around another massive star. This system is acting like a super hot sprinkler where instead of water, it is jetting out spirals of dust. 

Wolf-Rayet stars are known for having hot jets driven by magnetic fields. As the two stars in this system orbit roughly every twenty years, the source of the jets – that Wolf-Rayet star – moves like a spinning sprinkler head and changes the source of the dust. This is leading to an amazing spiral that we have an odd side view of. The random alignment of this system has the two stars orbiting almost perpendicular to the plane of the sky, so the spiral we see is like the spiral of water flying away from that imaginary sprinkler head I keep mentioning.

This system isn’t just a case of really cool geometry. It is also a case of weird physics leading to a hot system producing dust – something usually found in cooler situations. According to co-author Anthony Moffat, who uses somewhat strong language: When the two [stars’] winds collide, all Hell breaks loose, including the release of copious shocked-gas X-rays, but also the (at first blush surprising) creation of copious amounts of carbon-based aerosol dust particles in those binaries in which one of the stars has evolved to He-burning, which produces 40% C in their winds.

This system has it all – geometry, chemistry, and physics.

More Information

Subaru Telescope press release 

Keck Observatory press release 

“Resolving Decades of Periodic Spirals from the Wolf-Rayet Dust Factory WR 112,” Ryan M. Lau et al., 2020 September 15, The Astrophysical Journal (preprint on arxiv.org)