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Wolf-Rayet star

A Wolf-Rayet star is a rare, massive, and extremely hot star characterized by strong stellar winds and significant mass loss. These stars are in a late stage of stellar evolution, often preceding a supernova explosion, and are known for their broad emission lines of ionized elements in their spectra.

Source: science.nasa.gov

APODs including "Wolf-Rayet star"

The Cranium Nebula from the Webb Telescope

09/03/2026

The Cranium Nebula from the Webb Telescope
Image Credit: NASA Astronomy Picture of the Day

What's going on inside the head of this nebula? Dubbed the Exposed Cranium Nebula for its similarity to the human brain, what created the nebula remains a mystery. One thought is that the Cranium Nebula, also known as PMR 1, is a planetary nebula surrounding a white dwarf star. In this mode, the outer atmosphere was expelled when the original Sun-like star ran out of central nuclear fuel and contracted. A competing thought is that the central star is much more massive, possibly a Wolf-Rayet star, that is ejecting gas and dust via turbulent stellar winds. Adding to the intrigue is the dark vertical central division and the thin outer gaseous shell. The featured image was taken by the Webb Space Telescope in mid- infrared light, while a second image, included as a rollover, is in near-infrared. Future observations may reveal if this brainy system will quietly just fade from view or, many years from now, suddenly erupt in a powerful supernova.