Astronomers at the University of Warwick say WD J1330+6435, a cool white dwarf about 300 light-years away, is the first genuinely green star known. Sodium from rocky debris in its very dense atmosphere absorbs the orange part of its light, leaving a chartreuse green. The find comes from a study of 151 nearby white dwarfs: 146 look warm white, two yellow and three pink, one of them perhaps the reddest star known. The colours are computed from spectra; you cannot see this green with the eye or a telescope.
The first green star: what astronomers actually found
There are red stars, orange, yellow, white and blue ones, but never green. Astronomers at the University of Warwick now say they have found the first genuinely green star: WD J1330+6435, a white dwarf roughly 300 light-years away. The study, led by Mark Hollands with Boris Gänsicke, appeared in RAS Techniques and Instruments in October 2026.
A white dwarf is the dead core left behind when a star like the Sun runs out of fuel. This one is about 4,000 °C, cool for a white dwarf, and its atmosphere is polluted with calcium, lithium and sodium from rocky material it pulled in from its own former planetary system. That is the “zombie star that ate its planets” in the headlines.
Why green? Sodium eats the orange
A white dwarf’s atmosphere is extraordinarily dense: in the coolest ones it reaches about 1 gram per cubic centimetre, roughly the density of water and millions of times denser than the Sun’s surface. Squeezed like that, trace elements absorb a much wider band of light than they would in a normal star.
Here the sodium absorbs the orange part of the spectrum. Take orange out of an otherwise warm-white glow and what your eye sees is a chartreuse green. “Imagine standing on a planet and looking up at a green star,” Hollands said.
StarWD J1330+6435, a white dwarf
Distance≈ 300 light-years (reports: 284–326)
Temperature≈ 4,000 °C
Why greensodium absorbs the orange light
TeamM. Hollands, B. Gänsicke (Warwick)
PaperRAS Techniques and Instruments, Oct 2026
How a white star turns green
Original Astrometrik animation, simplified. Left: a warm white spectrum loses its orange band to sodium in a dense atmosphere, and the colour the eye would see shifts to green. Right: of 151 white dwarfs within about 65 light-years, 146 look warm white; two look yellow and three pink (colours computed from spectra, as in the study).
A colourful family of dead stars
The green star came out of a wider study. No white dwarf is bright enough for its colour to be seen directly, so the team took the spectra of 151 white dwarfs within about 65 light-years and ran them through a model of human colour vision. 146 of them glow warm white, “like a light bulb”. “The average white dwarf really is white,” Gänsicke said, which also corrects the common picture of white dwarfs as blue.
Five are different: two yellow, from dust and rocky debris, and three pink, where carbon dredged up from inside forms molecules. WD J1011+2845, 48 light-years away, glows a deep salmon pink and may be the reddest star on record; cooler white dwarfs with mixed hydrogen-helium atmospheres can look cyan. That is about one white dwarf in 30 with an unusual colour.
Can I see it? Honest caveats
No. At roughly 300 light-years a cool white dwarf is far too faint for the eye or a backyard telescope, and even a big telescope shows it only as a faint point too dim for our colour vision. The “green” is what the star would look like if you were close enough, worked out from its spectrum; it is a computed colour, not a photograph. The team also says only that no other star has been credibly reported as green.
The Sun will end the same way. In roughly 5 billion years it will swell into a red giant, shed its outer layers and leave a white dwarf about the size of Earth. Whether it turns out warm white, yellow or something stranger will depend, as with WD J1330+6435, on what falls onto it.
The colours of white dwarfs
Computed colours from the study (what the eye would see up close):
WD J1330+6435green · ≈ 300 ly · sodium
WD J1011+2845salmon pink · 48 ly · carbon
WD J0902+2010pink · carbon molecules
debris-rich white dwarfsyellow · dust and rock
cool H–He mixescyan · pale blue
146 of 151warm white, like a bulb
Viral claims, checked
What social posts say about the green star, and what the study supports:
TrueAstronomers found the first green starYes: the Warwick team says no other star has been credibly reported as green. The colour is computed from the spectrum, not photographed.
PartlyA zombie star that ate its planetsIt is a dead star whose atmosphere holds debris from rocky bodies of its old planetary system. Nobody saw whole planets being swallowed.
FalseYou can see the green star in the night skyNo. At about 300 light-years it is far too faint for the eye or a backyard telescope, and too faint to show colour even in big ones.
FalseThe Sun will turn into a green starUnknown. The Sun will become a white dwarf in about 5 billion years, but most white dwarfs look warm white; colour depends on what falls onto them.
See real star colours tonight
White dwarfs are invisible to the eye, but some bright stars show their colour plainly: orange Betelgeuse and blue-white Rigel in Orion, up in the late evening this time of year. Tap a button: the camera view points you to them with arrows.
Astronomers at the University of Warwick say WD J1330+6435, a white dwarf about 300 light-years away, is the first genuinely green star known. Sodium in its dense atmosphere absorbs orange light, leaving a green colour.
Why are there no green stars normally?
A normal star shines across all colours at once. When the peak of its light falls in the green, the mix still looks white to us, so stars look red, orange, yellow, white or blue, but not green.
Can you see the green star with a telescope?
No. It is far too faint to show colour even in large telescopes. Its green colour was computed from its spectrum with a model of human colour vision.
What colour are white dwarfs?
Most are warm white: 146 of 151 white dwarfs within about 65 light-years. A few look yellow, pink or cyan because of elements in their very dense atmospheres; about one in 30 has an unusual colour.
Sources and calculation
Sources: M. Hollands, B. Gänsicke et al., RAS Techniques and Instruments (October 2026), DOI 10.1093/rasti/rzag069, as reported by BBC Sky at Night Magazine (16 October 2026), Space.com (15 October 2026), Gizmodo and ScienceDaily (October 2026) and Universe Today (24 October 2026). Reported distances of WD J1330+6435 differ (284 and 326 light-years), so we give about 300.
Positions and times were recalculated with Astronomy Engine, the sky-calculation library Astrometrik uses; times for Vienna and Istanbul are local time. The artwork on this page was drawn by Astrometrik.