As to the spectral type, the stars with great proper motions are all yellow or red stars.
They are of a spectral type approximately solar; no Orion, Sirian or Arcturian stars having been found among them.
Morey set to work at once with the telescope; trying to find the nearest star of spectral type G-0, as had been agreed upon.
On the distances and luminosities of stars of spectral type G as derived from their proper motions.
As Russell originally pointed out, giant stars of every spectral type have nearly the same luminosity.
|spectral type |
A classification system for stars based on the strength of their spectral lines, using the letters O, B, A, F, G, K, M, L, and T to denote a range from blue (as in blue giant stars) to dim red (as in brown dwarfs). The spectrum of a star correlates with its surface temperature, ranging from over 60,000°K (O type) to less than 3,500°K (L and T types). See also Hertzsprung-Russell diagram.