A white dwarf called WD J1330+6435 would look chartreuse green to a nearby human observer, according to research highlighted by the University of Warwick on October 15. The result comes from interpreting the star’s spectrum with a model of human vision, rather than taking a close-up photograph of a green stellar surface.
The distinction matters. Astronomical images often assign visible colors to selected wavelength bands, sometimes including radiation our eyes cannot see. This study instead asks a specific question: what color would the light actually appear if we could see the star under suitable viewing conditions?
Dense atmospheres change the palette
Ordinary stellar colors largely follow temperature. In the very dense atmospheres of some cool white dwarfs, however, chemical absorption spreads across broad wavelength ranges. Warwick’s team links the green example to an atmosphere enriched with rocky debris, including sodium, calcium and lithium. Sodium removes enough orange light to alter the overall perceived hue.
Other compositions produce other results. Carbon-rich examples can look pink or purple, while some mixed hydrogen-and-helium atmospheres appear cyan. Most white dwarfs remain much less exotic: five of the 151 objects in the study’s nearby sample had unusually strong colors. Warwick’s account explains the atmospheric chemistry.
A calculation, not a new colored photograph
The paper combines observed and modeled spectra with established color-science functions, then converts the results into displayable colors. Its authors also account for the way brightness changes toward the edge of a stellar disk. Computer displays cannot reproduce a star’s actual surface brightness, so these visualizations reproduce chromaticity, not the experience of looking directly at a nearby star.
That makes the work useful beyond an eye-catching headline. It offers a physically grounded way to depict faint stellar remnants, while showing why an astronomical object’s name need not describe every member of its class. The research manuscript, posted October 13 and accepted by RAS Techniques and Instruments, documents the method and its limits.
Reporting checked October 20, 2026 (UTC). Catch-up coverage of the October 15 announcement.
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