NASA's Astronomy Picture of the Day (APOD) for 22 October 2026 features WD J1330+6435 and calls it the first green star. The designation marks it as a white dwarf, the small, dense core left behind when a Sun-like star dies.
Stars almost never look green. A normal star gives off light across the whole visible spectrum, and that mix shows up as red, orange, yellow, white or blue. Green sits in the middle of the spectrum, so a star whose light peaks there still looks whitish. For an object to look truly green, its light has to be shaped in an unusual way, for example by the elements in its atmosphere.
The APOD entry includes a short explanation by a professional astronomer. Readers can find the image and the full description of why this white dwarf stands out on NASA's APOD page.
