B-V to Kelvin formula

Posted by PeanutPower on Stack Overflow See other posts from Stack Overflow or by PeanutPower
Published on 2010-03-11T17:11:49Z Indexed on 2010/03/11 17:19 UTC
Read the original article Hit count: 373

Filed under:

astronomy

|

colors

|

JavaScript

Whilst looking for a "B-V color index to temperature conversion formula"

I found this javascript:

   var C1 = 3.979145;
   var C2 = -0.654499;
   var C3 = 1.74069;
   var C4 = -4.608815;
   var C5 = 6.7926;
   var C6 = -5.39691;
   var C7 = 2.19297;
   var C8 = -.359496;
   bmv = parseFloat(BV);
   with (Math) {
           logt=
              C1
             +C2*bmv
             +C3*pow(bmv,2)
             +C4*pow(bmv,3)
             +C5*pow(bmv,4)
             +C6*pow(bmv,5)
             +C7*pow(bmv,6)
             +C8*pow(bmv,7);

          t=pow(10,logt);
   }

Which is supposed to convert B-V color index to temperature. Does anyone understand how this is working and if the output value is an approximation for temperature in celcius or kelvin?

Is it something to do with products of logarithms?

© Stack Overflow or respective owner

Related posts about astronomy

Composite Moon Map Offers Stunning Views of the Lunar Surface [Astronomy]

as seen on How to geek - Search for 'How to geek'
Researchers at Arizona State University have stitched together a massive high-resolution map of the moon; seen the moon in astounding detail. Using images fro the Lunar Reconnaissance Orbiter (LRO) they carefully stitch a massive map of the moon with a higher resolution than the public has ever… >>> More
This Week in Geek History: Morse Code, Mars Rovers, J.R.R. Tolkien’s Birthday

as seen on How to geek - Search for 'How to geek'
Every week we bring you interesting facts from the history of Geekdom. This week in Geek History witnessed the first successful demonstration of the electric telegraph, the safe landing of the Spirit rover on the surface of Mars, and the birth of famed fantasy author J.R.R. Tolkien. Latest… >>> More
Earth’s Radiation Belt Sounds like Whale Song [Video]

as seen on How to geek - Search for 'How to geek'
The radio frequencies of Earth’s radiation belt have uncanny resemblance to a sort of whale/bird song remix. Check out this video to learn more about NASA’s efforts to explore the belts and listen to the Earth’s song. When we hear the “song” of the Earth, exactly what… >>> More
Van Gogh’s Starry Night Rendered in Hubble Telescope Images

as seen on How to geek - Search for 'How to geek'
The process of making a large image out of mosaic of smaller image “pixels” is certainly nothing new; this rendition of Starry Night using images from the Hubble telescope, however, is a particularly fitting use of the technique. Crafted by Alex H. Parker, a researcher at the Harvard-Smithsonian… >>> More
Curiosity’s Descent to Mars in HD [Video]

as seen on How to geek - Search for 'How to geek'
Thanks to the Mars Descent Imager (MARDI) mounted on the fore-port side of Curiosity we’re treated to a high-resolution video of Curiosity’s descent to Mars. The video from MARDI, combined with the video editing of YouTube user DLFitch, yields the above video. He writes: This is a full-resolution… >>> More

Related posts about colors

urxvt bold colors are wrong - bold #0-7 are using colors from #8-15

as seen on Super User - Search for 'Super User'
My colors are off. Specifically, the bold version of colors 1-6 is broken: The color of each (emboldened) index should match the color of the text beside it. It does not. This is generated from this gist, modified to enumerate colors 0-15 instead of 16-256. Update: Here's what's going on: Bold… >>> More
make emacs in a terminal use dark colors and not light font-lock colors

as seen on Stack Overflow - Search for 'Stack Overflow'
I am using emacs on MacOS 10.6 with Terminal. I have a white background. It's very hard to read quoted C++ strings. They are coming up in pale green. Keywords are in turquoise. After searching through the source I cam across cpp.el and have determined that I am using the cpp-face-light-name-list… >>> More
How can I make gnome-terminal not transparent?

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
When I use gnome-terminal the background is annoyingly slightly-transparent. Here you can read the ubuntu.stackexchange.com site through the background. Bigger image These are the background options I have, which are set to "not transparent". I have the desktop visual effects set to "Normal"… >>> More
Text editor with coloring to highlight "non-parameters" in conf files?

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
Some .conf files have a lot of comments and parameters in them like so: # WINS Server - Tells the NMBD components of Samba to be a WINS Client # Note: Samba can be either a WINS Server, or a WINS Client, but NOT both ; wins server = w.x.y.z # This will prevent nmbd to search for NetBIOS names through… >>> More
Black & White Video with Youtube

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
Hey'a guys, I have an issue with the Youtube Player within Ubuntu, it seems that when playing videos there in black & white, no matter if there normal or HD. I kind of figured out how to prevent this from happening by deleting the cookie PREF that holds a KV Pair like so: PREF f1=50000000&fv=10… >>> More