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Green-Coloured White Dwarf Identified 280 Light-Years Away in Draco
Astronomers identify an unusual green-coloured white dwarf, WD J1330+6435, located about 280 light-years from Earth in the constellation Draco. The finding is reported as a rare stellar colour observation, with researchers using spectral data and human colour-perception models to determine its chartreuse-green appearance.
Green-Coloured White Dwarf :
| Dimension | Key Details |
|---|---|
| White dwarf definition | A white dwarf comprises the super-dense, glowing leftover core of a dying, low- to medium-mass star after it runs out of nuclear fuel. |
| White dwarf physical features | A white dwarf has an estimated temperature of around 4,000 degrees Celsius and is extremely compact, roughly comparable in size to Earth. |
| Object identified | WD J1330+6435 comprises an unusual green coloured white dwarf. |
| Location | WD J1330+6435 is located about 280 light-years from Earth in the constellation Draco. |
| Light-year definition | A light-year comprises the distance light travels in 1 year, around 9.46 trillion kilometres. |
| Observation time-lag | The light travelling from WD J1330+6435 takes approximately 280 years to reach Earth, and observing it today effectively shows it as it appeared 280 years ago. |
| Reason for green appearance | The chartreuse green appearance is governed by the interaction of sodium and helium in the dense atmosphere, which modifies the wavelengths of light absorbed by the star. |
| Other spectral influence | Under these conditions, sodium interacts with helium in ways that alter absorbed wavelengths, and other elements, including calcium, also influence its spectrum. |
| Method used to determine appearance | Researchers use spectral data and models of human colour perception to calculate how the star appears, rather than relying on a direct photograph showing it as green. |
| Colours of normal stars | Normal stars comprise colours that are pretty much only orange, white, or blue. |
| Study inference on white dwarf colours | The study suggests that white dwarfs may exhibit a wider range of colours, including pale blue, cyan, pink, purple, and green, depending on atmospheric chemistry. |
| Another white dwarf in study | WD J1011+2845 shows a salmon-pink appearance due to its carbon-rich atmosphere. |