AAS 2009: Brown dwarfs ain't so brown
Kenneth Brecher, an astrophysicist at Boston University, gave a funny little talk today called 'How now brown cow dwarf'. The title of his talk, he says, is as meaningless as the term 'brown dwarf'. It's one of his many concerns with light perception at Project LITE, an umbrella for the psychophysical color experiements he runs.
'Brown dwarf' was coined in the 1970s by Jill Tarter, now director of the SETI institute, and it was a term that stuck. “It was a mistake,” says Brecher. “'Infrared dwarfs' would have been a much better name.”
The problem is that brown is a subtractive color -- made by 'desaturating' yellows and oranges with black. But since brown dwarfs are emissive bodies -- they glow -- they by definition can't be brown.
Now Brecher knows that he's not going to change astronomers from using a term that is so much a part of the vernacular. But just like many involved in the debate over what constitutes a planet, Brecher seems to be a scientist who cares very much about names and definitions. “Astronomy is riddled with historical artifacts that nobody in their right mind would use today.”
Here is Brecher holding a neon light, glowing with the color that he says we would perceive a brown dwarf emitting: yellowish-orange. Note, however, that Brecher is wearing a brown jacket.
Comments
Greetings. Great stuff.
Yes, I see the hex code for the color: EB4B25, but I would like to know for what spectral type, temperature and atmosphere this color stands for ( L-type?, T-type? dusty atmosphere? etc) as well as to ask if we don't have green stars because of a similar reason we don't have brown stars.
One more question: is this
EB4B25 color the color one could see if the sun where a brown dwarf located few tenths or hundredths of A.U.'s away from us?
Very thanks!
Posted by: Bruno Alessi | January 7, 2009 03:08 PM