Is there a flaw with the newer purposes and correlations attributed to the HR diagram? (And would a third axis of mass correct the enclosed flaw?)
When I was younger, I was looking at HR diagrams, and began to experiment with the HR diagram. I was looking at plotting different groups of stars on the HR diagram when I found RV Tauri stars. ...
Considering that a star of certain declination is crossing the local meridian at the observer's zenith at an unknown location on the earth. Here, the declination of the star is equal to the observer's ...