Astronomers Discover the First Green Star (space.com) 30
Astronomers have identified what may be the first genuinely green star, a white dwarf called WD J1330+6435 located about 326 light-years from Earth. Space.com reports: The researchers found that some dead star white dwarfs can go a little green around the gills after snacking on orbiting planets. An example of this is WD J1330+6435, a cool white dwarf located around 326 light-years away, which has been accreting rocky material from a planetary companion. This has enriched its atmosphere with calcium, lithium, and sodium, and the team's model suggests this would have led WD J1330+6435 to adopt a green hue.
[...] The researchers think that no other star, living or dead, has ever been credibly reported as green. That makes WD J1330+6435 the first known genuinely green star. "The traces of sodium in the atmosphere of this white dwarf absorb the orange part of the spectrum, leaving behind a ghostly green glow," Hollands said. "Imagine standing on a planet and looking up at a green star. It feels like something out of science fiction." The researchers also discovered what may be the reddest star ever observed, the white dwarf WD J1011+2845, located just 48 light-years away.
The findings have been published in the journal RAS Techniques and Instruments.
[...] The researchers think that no other star, living or dead, has ever been credibly reported as green. That makes WD J1330+6435 the first known genuinely green star. "The traces of sodium in the atmosphere of this white dwarf absorb the orange part of the spectrum, leaving behind a ghostly green glow," Hollands said. "Imagine standing on a planet and looking up at a green star. It feels like something out of science fiction." The researchers also discovered what may be the reddest star ever observed, the white dwarf WD J1011+2845, located just 48 light-years away.
The findings have been published in the journal RAS Techniques and Instruments.
Methinks... (Score:2)
Perhaps they were a trifle hasty in naming that class of star white dwarf.
Dietician to the Stars. (Score:1)
..dead star white dwarfs can go a little green around the gills after snacking on orbiting planets..
Forget color. How is that, given a dwarf name?
I’m not dietary cosmologist, but anything eating planets does not conjure up a wee bit of impact by those chasing Darby O’ Gill Under the Rainbow..
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I vote for calling them Green Hobbits.
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Well, thanks to what we learned from the IAU in the Pluto debacle, where "dwarf planets" are not classified as planets, I look forward to dwarf stars not even being classified as stars soon enough ;) And wait until dwarf galaxies get kicked out of the galaxy club! ;)
Re: Dietician to the Stars. (Score:3)
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Forget color. How is that, given a dwarf name?
Sol is a yellow dwarf. If our Sun is considered so small to be a dwarf star, it is terrifying to imagine the kind of Lovecraftian horrors must inhabit this universe.
Re:Dietician to the Stars. (Score:5, Insightful)
The sizes are already out of this world and trying to really comprehend the enormous size differences between celestial bodies is likely beyond our imagination. Sure, we can "know" the sizes with numbers but to really "feel" the enormity is unlikely. Our world feels large as an individual on the surface. Then to think of how large Jupiter is only to realize it's compared to the Sun and we go on from there.
Jupiter is nearly 11x larger in radius then the Earth and the Sun is roughly 10x larger then Jupiter. There are other stars in the universe that are as much as 1000x larger then our Sun and also stars about the size of Jupiter. But 1000x our Sun, the mind can't really appreciate this scale.
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We are amoeba trying to comprehend an elephant.
Green Lantern (Score:1)
I wonder if that is Oa's star?
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All praise the people of Kondal.
Green is (Score:1)
Re:Green is (Score:5, Informative)
I mean, normally green stars aren't real, to the human eye. The problem is that from a standard blackbody curve [libretexts.org], as you go up in surface temperature, by the time you've flipped the red-green cone activation ratio to the green side, you're getting so much blue that it looks like white instead. And then if you keep going, blue dominates and it turns blue. So it goes red, yellow, white, blue, not stopping for green. You also don't get purple because, for the most part, purple needs a strong red activation, little green, alongside at least a reasonable amount of blue - but with stars, the blue is way stronger than the red under a typical blackbody curve (there actually is a small shortwave red activation peak, so you *can* get purple purely with shortwave (like in a rainbow), but in the blackbody spectrum, the blue is so dominant that its not enough).
The trick here is that specific emission and absorption spectra can deviate from a standard blackbody curve. It may seem weird because one is used to sodium emission lamps being orange. But in the star's ~4000K photosphere, pressure broadening smears out the sodium doublet into a massive absorption trough, absorbing red to yellow light. Accreted calcium also has a similar effect on the blue side of the spectrum. Look back at the 4000K blackbody curve in the above link, imagine even a relatively minor suppression in both red and blue, and you can see how it morphs into a curve that the eye will read as green. :)
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Obligatory green quotes... (Score:5, Funny)
"It is green" Scotty, ST
"It is..hm.. green" Data, STNG
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"Are we green?" - Korben Dallas
"(choking) Supergreen" - Ruby Rhod
Sun emits most energy in green color... (Score:2)
It is just addition of other wavelengths and subtraction of blue makes it seemingly yellow...
"It feels like something out of science fiction." (Score:2)
"Imagine standing on a planet and looking up at a green star. It feels like something out of science fiction."
I believe the late Lin Carter has this covered.
Copper ? (Score:2)
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Ummmm... where you getting the O2 from?
Well of course it's green (Score:5, Funny)
All stars are. They run 100% on solar energy.
Frist! to say (Score:2)
this https://www.youtube.com/watch?v=rRZ-IxZ46ng&list=RDrRZ-IxZ46ng&start_radio=1 [youtube.com]
They're about 15 years late (Score:3)
Of course, once astronomers have collected 120 regular stars and defeated Bowser twice, they'll unlock the 120 green stars.
I've already done this a few times.
Kermit says (Score:1)
"About" 326 light years? (Score:2)
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Let's stick with standard units.
The star is roughly 8.33 Kellel Runs from Earth.
Spectral class? (Score:2)
First green star (Score:2)
Dr Strange plucks it out of the sky (Score:2)
"There you are."