Do the magnitudes and colors of stars ever change?
I have an assignment in school where I have to estimate the magnitudes and colors of certain stars in certain constellations. I know that some stars in some constellations are brighter and considered either blue, yellow, or red depending on their temperature, but I was wondering if these magnitudes and temperatures are always going to be the same for those stars. For example if one star in a constellation is say 9,000k and 3.9 Magnitude, will it always be that? Or will it vary at all? A star will spend most of its lifetime turning hydrogen into helium in its core; this nuclear reaction releases energy and makes the star shine. During this phase, a given star’s colour and magnitude remain essentially the same (we call this phase of a star’s life the main sequence phase). Towards the end of its life, however, after the star runs out of hydrogen to burn into helium, the star’s outer layers expand and cool down; we call this its red giant phase. Since the temperature of the star’s outer en
