The James Webb Space Telescope has revealed a stunning sight: a system of four dust spirals in space, generated by two rare Wolf-Rayet stars. This discovery has surprised astronomers, as it challenges previous expectations and offers a unique insight into stellar evolution. The system, known as Apep, is a chaotic wonder, formed over 700 years by these extraordinary stars. With only 1,000 Wolf-Rayet stars thought to exist in our Galaxy, Apep is a rare and fascinating phenomenon.
The stars' orbits are a spectacle in themselves, with each star orbiting the other every 90 years, taking 25 years to complete one cycle. During this time, their stellar winds collide, creating huge discs of cosmic dust. The Webb Telescope's infrared image has captured this intricate dance, revealing four shells of dust rather than just one, as previously observed.
But the surprise doesn't end there. The system is more complex than anticipated. It's not just two stars; there's a third massive supergiant star involved. This star, with a wider orbit, carves holes in the expanding dust clouds, creating a unique pattern. All three stars appear as a single bright point in the Webb's image, a captivating sight.
Yinuo Han, a postdoctoral researcher at Caltech, describes the experience of viewing the new observations as akin to turning on a light in a dark room, revealing hidden details. The image is filled with dust, ejected in repetitive, predictable structures. This discovery has led to further research, with Ryan White, a PhD student at Macquarie University, releasing another paper on the system's unique characteristics.
The astronomers refined the orbits of the Wolf-Rayet stars by measuring the ring locations and comparing them with the speed of the dusty shells' expansion. This revealed an incredibly rare orbital period of 90 years, with each orbit taking 25 years. The stars emit dust at an astonishing speed of 2,000 to 3,000 km per second, making the system even more intriguing.
The third star's influence is evident in the central bright point of the image, where a faint V-shape can be traced. This star, gravitationally bound to the system, has carved a unique cavity in the dust, creating a funnel-like shape. The mystery of the precise distance to the stars from Earth remains, but the Webb Telescope has provided invaluable insights into this extraordinary stellar system.
The future of Apep is a supernova explosion, with the Wolf-Rayet stars potentially becoming black holes. This system's discovery and ongoing research highlight the power of modern telescopes and the endless wonders of the universe.
