![[Hampstead Scientific Society]](../../images/hss_logo_metallic.gif){kind=logo}
Spectral Interpretation 101
A cool star- Mira
![[Omicron Ceti]](./images/mira_obs_spectra.jpg)
Now we're looking at Mira, or Omicron Ceti, a star which is at the other end of the stellar temperature scale from Theta Ophiuchi, at about 3000 degrees. The star's atmosphere is cool enough so that titanium oxide (TiO) molecules can form and take these very dramatic bites out of the light coming from the star's interior. Molecules actually form narrow lines like the atomic lines in the solar spectrum, but there are so many of them bunched together that we get these wedge shaped formations known in the business as bands. The steep part of the wedge is a bandhead.
The D lines are the star's own.
Saturn and the doppler shift >>