NASA’s James Webb Space Telescope has delivered a first of its kind: a crisp mid-infrared image of a system of four serpentine spirals of dust, one expanding beyond the next in precisely the same pattern. (The fourth is almost transparent, at the edges of Webb’s image.) Observations taken prior to Webb only detected one shell, and while the existence of outer shells was hypothesized, searches using ground-based telescopes were unable to uncover any. These shells were emitted over the last 700 years by two aging Wolf-Rayet stars in a system known as Apep, a nod to the Egyptian god of chaos.
Webb’s image combined with several years of data from the European Southern Observatory’s Very Large Telescope (VLT) in Chile narrowed down how often the pair swing by one another: once every 190 years. Over each incredibly long orbit, they pass closely for 25 years and form dust.
Webb also confirmed that there are three stars gravitationally bound to one another in this system. The dust ejected by the two Wolf-Rayet stars is “slashed” by a third star, a massive supergiant, which carves holes into each expanding cloud of dust from its wider orbit. (All three stars are shown as a single bright point of light in Webb’s image.)
Webb’s mid-infrar …