Pleiades

Pleiades

I chose Pleiades because of its name as the Seven Sisters which I found interesting.
Chemicals: Lithium
Location: RA 03^h 47^m 24^s | Dec +24° 7′
Stellar Classification: B-type stars

In astronomy, the Pleiades, or Seven Sisters (Messier 45 or M45), is an open star cluster containing middle-aged hot B-type stars located in the constellation of Taurus. It is among the nearest star clusters to Earth and is the cluster most obvious to the naked eye in the night sky. Located at RA 03^h 47^m 24^s | Dec +24° 7′, the cluster core radius is about 8 light years and tidal radius is about 43 light years. The cluster contains over 1,000 statistically confirmed members, although this figure excludes unresolved binary stars. It is dominated by young, hot blue stars, up to 14 of which can be seen with the naked eye.

  In normal main sequence stars, lithium is rapidly destroyed in nuclear fusion reactions. Brown dwarfs can retain their lithium, however. Due to lithium's very low ignition temperature of 2.5 million kelvin, the highest-mass brown dwarfs will burn it eventually, and so determining the highest mass of brown dwarfs still containing lithium in the cluster can give an idea of its age. Applying this technique to the Pleiades gives an age of about 115 million years.



Sources:
Wikipedia, the free encyclopedia. (2015, September 23). Pleiades. Retrieved September 28, 2015, from https://en.wikipedia.org/wiki/Pleiades

Visible Spectra of the Elements. (n.d.). Retrieved September 28, 2015, from http://www.umop.net/spctelem.htm