It takes two giant stars – known as the Wolf-Rayet binary 140 – to interact more than five thousand light-years from Earth and more than a hundred years to create what is known from this Wednesday as “Cosmic Footprint”. The image was taken by the James Webb Telescope and released by NASA.
The formation of dust rings itself takes a long time: every eight years the stars pass close to each other and the collision of the solar wind “creates” a ring of dust. According to NASA’s interpretation, it is the flow of gas emitted by the stars that produces dust. And if the dust in the image looks like rings – like those on Saturn – according to astronomer Ryan Lau, then the three-dimensional geometry of the structures is crust-like.
“The regular spacing between the shells indicates that dust-forming events occur at the right pace: once every eight-year orbit. In this case, the 17 shells can be thought of as tree rings, showing more than 130 years of dust formation,” Ryan explains. Lau, who also confirms that NASA has compared the latest discoveries with engineering models of dust from Yinuo Han, Ph.D. Student at Cambridge University.
According to Lau, “the shells of the outermost binary star have traveled more than 70,000 times the distance from the Earth to the Sun, at speeds of about ten million kilometers per hour.”
To be more dimensionally aware, it’s worth noting that the Wolf-Rayet 140 binary consists of a Wolf-Rayet star that is at least 25 times the mass of the Sun and a blue giant star that would be even larger.
