{"id":935327,"date":"2026-10-16T15:34:08","date_gmt":"2026-10-16T15:34:08","guid":{"rendered":"https:\/\/www.newsbeep.com\/ca\/935327\/"},"modified":"2026-10-16T15:34:08","modified_gmt":"2026-10-16T15:34:08","slug":"a-green-star-has-been-identified-by-astronomers-for-the-first-time","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/ca\/935327\/","title":{"rendered":"A green star has been identified by astronomers for the first time"},"content":{"rendered":"

Open this photo in gallery:<\/a><\/p>\n

An artist’s impression of the cool white dwarf star WDJ1330+6435, which has accreted sodium-rich rocky material from its planetary system into its atmosphere.Mark A. Garlick\/University of Warwick\/via REUTERS<\/p>\n

Astronomers for the first time have identified a green star, documenting a dense stellar remnant called a white dwarf that became a ghostly shade of chartreuse after ingesting rocky debris from planets that once had orbited it.<\/p>\n

A star\u2019s colour typically is governed by its temperature, with cooler stars appearing orange, the sun and stars similar to it appearing white, and the hottest ones appearing a pale blue.<\/p>\n

But the formula is different for a white dwarf, which is the leftover core of a low- to medium-mass star that burned through its nuclear fuel and blew off its outer layers. Most white dwarfs have colours similar to other stars, and their average colour is white. But changes in their chemistry over time can turn some of them into rarer colours.<\/p>\n

The newly identified green one, named WD J1330+6435, is a white dwarf in the Milky Way galaxy that is located about 280 light-years from Earth in the constellation Draco. A light-year is the distance light travels in a year, 9.5 trillion km.<\/p>\n

\u201cWe first became interested in this white dwarf because bits of planetary material have fallen onto its surface, enriching its outer layers in elements including calcium, lithium and, in particular, sodium,\u201d said astrophysicist Mark Hollands of the University of Warwick in England, lead author of the study published in the journal RAS Techniques and Instruments.<\/p>\n

In normal stars, sodium absorbs a very specific wavelength of orange \u2013 the same orange that gives sodium street lamps their characteristic colour.<\/p>\n

\u201cIn this particular white dwarf, however, the density is so high that the sodium atoms are constantly being bombarded by surrounding helium atoms, which alters the sodium atomic energy levels,\u201d Hollands said.<\/p>\n

\u201cThe end result is that the sodium atoms no longer absorb one very narrow wavelength of orange \u2013 they absorb the yellows, oranges and some of the red wavelengths. And what you\u2019re left with is a star that has a beautiful chartreuse green glow, something that wouldn\u2019t be possible for sun-like stars,\u201d Hollands said.<\/p>\n

The discovery was part of a project assessing the colour of white dwarfs as human eyes would see them. A white dwarf typically has half the mass of the sun compacted into the size of Earth.<\/p>\n

\u201cBecause white dwarfs are super-dense stars \u2013 they are roughly the size of the Earth, but contain about 165,000 times its mass \u2013 even a small amount of sodium blocks out a large amount of the orange light coming out of the star,\u201d University of Warwick astrophysicist and study co-author Boris G\u00e4nsicke said.<\/p>\n

\u201cIn the end, it\u2019s all very similar to the mixing of colours in the palette of a painter. They start with a few basic colours, then mix them together to form any colour they need for their painting. Take away some of the colour going into the mix, and the output will change,\u201d G\u00e4nsicke said.<\/p>\n

A star that is salmon pink<\/p>\n

The researchers studied 151 white dwarfs located within about 65 light-years of Earth, with white the average colour.<\/p>\n

One showed perhaps the reddest hue of any known star, a salmon pink. Named WD J1011+2845, it is located 48 light-years from Earth in the constellation Leo Minor. This time, it was not sodium that was changing the palette, but carbon.<\/p>\n

\u201cRather than something hitting the star, in this case the carbon comes out from its deep interior,\u201d G\u00e4nsicke said.<\/p>\n

Data used by the researchers included light spectrum observations from the Sloan Digital Sky Survey using a telescope in New Mexico, as well as white dwarf spectrum models they developed.<\/p>\n

They found that white dwarf colours divide into distinct groups based on atmospheric composition. Carbon-rich white dwarfs usually were pink or purple. Those enriched with debris from shattered remnants of planetary systems leaned toward yellow. Lower-temperature white dwarfs with mixed hydrogen and helium atmospheres tended toward a cyan or pale blue hue.<\/p>\n

In all, they spanned almost every colour of the spectrum.<\/p>\n

While WD J1330+6435 was the first documented example of a green star in the real world, green stars have existed in science fiction, including in the recent comic book movie \u201cSupergirl.\u201d<\/p>\n

\u201cIt does show that the universe is sometimes just as weird as anything science fiction can conjure up,\u201d Hollands said.<\/p>\n","protected":false},"excerpt":{"rendered":"Open this photo in gallery: An artist’s impression of the cool white dwarf star WDJ1330+6435, which has accreted…\n","protected":false},"author":2,"featured_media":935328,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[901,888,902,879,877,903,49,48,876,895,896,891,878,875,46,549,295,894,887,914,880,881,893,889,890,884,904,885,909,910,912,907,911,905,908,882,898,899,714,897,906,66,865,61,900,892,886,883,913],"class_list":["post-935327","post","type-post","status-publish","format-standard","has-post-thumbnail","category-science","tag-alberta","tag-arts-news","tag-bc","tag-breaking-news","tag-breaking-news-video","tag-british-columbia","tag-ca","tag-canada","tag-canada-news","tag-canada-sports","tag-canada-sports-news","tag-canada-trafficcanada-weather","tag-canadian-breaking-news","tag-canadian-news","tag-economy","tag-education","tag-environment","tag-federal-government","tag-foreign-news","tag-globe-and-mail","tag-globe-and-mail-breaking-news","tag-globe-and-mail-canada-news","tag-government","tag-life-news","tag-lifestyle","tag-local-news","tag-manitoba","tag-national-news","tag-new-brunswick","tag-newfoundland-and-labrador","tag-northwest-territories","tag-nova-scotia","tag-nunavut","tag-ontario","tag-pei","tag-photos","tag-political-news","tag-political-opinion","tag-politics","tag-politics-news","tag-quebec","tag-science","tag-sports-news","tag-technology","tag-travel","tag-trudeau","tag-us-news","tag-world-news","tag-yukon"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/posts\/935327","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/comments?post=935327"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/posts\/935327\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/media\/935328"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/media?parent=935327"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/categories?post=935327"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/tags?post=935327"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}