Astronomers Discover New Types of Stars

Astronomers have discovered a white dwarf whose light could appear green to the human eye.

Scientists identified the unusual hue from spectral data, since the star cannot be observed directly from Earth.

White dwarfs are dense, fading remnants of Sun-like stars that have completed the main stage of their evolution.

Experts studied the spectra of 151 such objects located within 65 light-years of Earth.

According to the study’s lead author, University of Warwick astrophysicist Mark Hollands, the unusual color of one of the white dwarfs is linked to the presence of calcium, sodium, and lithium in its atmosphere.

“Ordinary stars are usually orange, white, or blue,” Hollands said.

The unusual shades of white dwarfs are caused by interactions between helium and mixtures of other chemical elements.

In addition to the green object, astronomers also discovered a star that may appear pinkish because of a high concentration of carbon molecules.

According to Hollands, the new observations could increase tenfold the number of white dwarfs with available spectral data.

This could allow scientists to search for other stars with unusual colors.