Wondering around in The Sky X, i saw this very deep red colored star and thought of taking its spectra. It is relatively a bright star and to keep the ADU counts in control, 10 seconds of exposure seemed fine. I got 150 images in total, hence a 25 minutes of total exposure.
This (HIP 105562) is an M7 class star, a very cold star, relative to the stellar temperatures. The estimated age of M class stars (main sequence lifetime on H-R Diagram) is actually much more than the lifetime of the Universe, which means this Universe in all its age of around 14 billion years has yet to see a death of a single M star! Any star that is born as an M type will live trillions of years!!
Since they are very cold so they are not bright in the night sky. You cannot see most M type stars with your eyes only, from any of the best night sky locations on earth. Our Sun has most of its neighbors of M class stars, about 75% of all the closest stars. Proxima Centauri, our nearest star to our sun is infact an M star and it will live some 4 trillion years.. talk about lifetime!
Such low temperature in these stars allow to create molecules in their atmospheres. I could easily locate Titanium Mono Oxide (TiO) absorption bands all over the spectrum of this star. Calcium (Ca) is there at 4227 angstrom. Famous Sodium Doublet (D1 and D2) are at 5896 5889 angstroms. Present Calcium form a bond with Hydrogen and makes Calcium monohydride (CaH) at 6750 angstrom.
Here is the calibrated and Normalized Spectrum from Rspec: