OBAFGKMLTY
Posted by BC on April 11th, 2008
Spectral types have a new addition. The “Y” type star is now included in the family. The “Y” stars are very cool at approximately 350 degrees C. They do not emit enough energy to see in the visible range, but can be seen in the infrared region. A brown dwarf has the mass of about 80 Jupiters, so it cools shortly after forming.
(The brown dwarf is in the yellow circle.)
The coolest “Y” type star so far, a brown dwarf designated CFBDS J005910.83-011401.3, has been found about 40 light years away in Pisces. It is believed to have the mass of between 15 and 30 Jupiters and is between 1 billion and 5 billion years old. This particular brown dwarf is being looked at as a link between brown dwarves and giant planets.
More information on this brown dwarf can be found at the Sky & Telescope site, the discovery group’s press release, or their article.
3 people have commented
Matthew Ota said,
April 20th, 2008 @ 1:33 pm
Twenty years ago, the “new” classifications beyond “OBAFGKM” was
“RNS” (Oh BE A Fine Girl/Guy Kiss Me Right Now Sweety).
I wonder what happened to the R, N and S stars?
BC said,
April 26th, 2008 @ 6:55 pm
Here is the WIKI site url: http://en.wikipedia.org/wiki/Stellar_classification
I have not found info on the R, N and S types. Anyone?
Lydia said,
May 3rd, 2008 @ 9:40 pm
According to what Harvard Classification System ( HAH-VAHD?:-)
Cool star types include R and N (or C-type carbon stars with temps under 3,000 K). S class resemble class M stars but with prominent zirconium oxide instead of titanium oxide spectral bands.
Any other thoughts on this?
LL
