Trevino Terry

The #JWST has recently given us one of the most beautiful images of recent years: the stellar system Apep, a trio of massive stars surrounded by four perfect dust spirals that look almost drawn by hand. At the center are two Wolf-Rayet stars, both rich in carbon and stripped of their outer layers by ferocious winds. Every 193 years they come close enough for their winds to slam into each other at 2000–3000 km/s and condense into tiny grains of amorphous carbon dust. Each periastron passage leaves a new shell behind; the four we now see were created over the last seven centuries and are still expanding at about 1000 km/s. A third star, a luminous O-type supergiant, orbits farther out and literally punches conical holes through every shell as it passes. It is the first time we have directly seen a companion star destroying dust produced by a colliding-wind binary. The shells are incredibly regular, yet show small azimuthal asymmetries (around 10–20 %) and a temperature that drops slowly with radius, exactly as expected for carbon dust heated by the central stars. Apep remains a puzzle in one respect: its distance is still uncertain, between roughly 2.8 and 5.1 kiloparsec — that is, 9100 to 16 600 light-years. Until we pin that down, we cannot be completely sure how fast the winds really are and whether one of the Wolf-Rayet stars is rotating so quickly that it could end its life in a long gamma-ray burst. For now, it is simply the most spectacular laboratory we have for watching massive stars manufacture and destroy the raw material of future planets, one spiral at a time. References Release➡️science.nasa.gov/missions/we… 'The Serpent Eating Its Own Tail: Dust Destruction in the Apep Colliding Wind Nebula', Ryan M. T. White et al 2025 ApJ 994 121➡️iopscience.iop.org/article/1… 'The Formation and Evolution of Dust in the Colliding-wind Binary Apep Revealed by JWST', Yinuo Han et al 2025 ApJ 994 122➡️iopscience.iop.org/article/1… Image: NASA, ESA, CSA, STScI; Simulation: Yinuo Han (Caltech), Ryan White (Macquarie University); Visualization: Christian Nieves (STScI); Image Processing: Alyssa Pagan (STScI)