When we look up at the Sun, we see a star glowing in shades of yellow, orange, and white. Across the universe, stars display a range of colors, from fiery reds to brilliant blues, with their hues shaped primarily by their surface temperatures. But what if the stellar palette extends beyond the colors we’re accustomed to seeing? New findings are bringing some unexpected possibilities into view, suggesting that white dwarfs, the dense remnants of dead stars, could glow in shades of pink, purple, and even green.

For the first time, astronomers have spotted a star that appears green to the human eye. The star had reached the end of its lifespan and swallowed up rocky material from its planetary system, giving it a chartreuse green appearance. The findings, published in RAS Technique and Instruments, suggest that planetary debris can cause white dwarf stars to shine in a whole array of colors if viewed up close.

When a star like the Sun burns through its nuclear fuel, it sheds its outer layers to form a planetary nebula, leaving behind its dense, dead core in the center. These cosmic zombies, known as white dwarfs, are extremely hot and have been known to shine in a white/pale blue. (The hotter a star is, the more of its light is emitted through shorter, bluer wavelengths.)

“Most stars, including most white dwarfs, behave like ‘perfect radiators,’ so their color is set almost entirely by temperature. But nobody had really looked into what else might be possible for white dwarfs,” Mark Hollands, an astronomer at the University of Warwick in England who led the work, said in a statement .

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