newjerseyrunner said:
That makes sense, while most of the stars in the universe are smaller and dimmer than the sun, the ones that are visible to us will obviously be brighter.
This is true, but not obvious.
To the contrary, it is a significant observation about Milky Way and solar neighbourhood.
Looking to the brightest stars...
Out of the 92 brightest stars of the sky, up to +2,50, all of them are brighter than Sun as mentioned. (Alpha Centauri B would be 21st if it were resolved, which it is not). In face, the brightest star in sky to be dimmer than Sun, Tau Ceti, is about 290th place.
Now, the nearest and dimmest of these 92 is Alpha Centauri AB.
6 of the 92 are within 25 ly of the Sun: Alpha Centauri, Sirius, Procyon, Altair, Vega, Fomalhaut.
The median distance, to 46th of the 92, is 170 ly.
The most distant 6, understandably at hard to know distances (too far for parallax) are over 1100 ly - the most distant being guessed to be Deneb Cygni estimated at 2600 ly.
If you look at the colour of these stars, the result is:
4 O stars
30 B stars
20 A stars
...making up 54 stars. All of these are massive young stars.
The remaining 38?
8 F stars, only 1 of which is arguably a dwarf
around 2 G stars, significantly double (Alpha Centauri and Capella)
and then about 20 K stars and 6 M stars, all of which are giants or supergiants.
Looking at distances again, 3 nearest giants are Pollux at 34 ly, Arcturus at 37 ly and Capella at 42 ly.
Then, within 100 ly of Earth, the 92 brightest stars include further 7 K and 1 M giant. The same distance, up to 100 ly, includes the 1 G dwarf, 1 arguable F dwarf (Procyon which may be subgiant), 1 F giant (Beta Cassiopeiae) - the rest are 16 A stars and 5 B stars.
What are these 11 nearby giants?
Capella is a double, so its masses are known - and happen to be big.
Whereas Arcturus, though single, is alleged to be low mass old stars.
Many of the remaining 9 simply have no mass alleged - understandably, as they are single.
How common, among the giants in solar neighbourhood, are young massive stars at the end of their short life, compared to lower mass stars at the end of a long life?