# What Would the Sky Look Like If the Sun Were a Different Color (And Still Half a Degree Wide)? [duplicate]

This question has been asked many, many, many times--what would the sky look like if the sun were a different color? But the mistake I keep seeing is that they used actual stars and imagined Earth as orbiting those different stars from one same distance--93 million miles, or one AU.

So let me differ this up. If the sun were of a color different from yellow--like orange, blue, red or yellow-white--but still measures in at an angular distance of half a degree, then in regards to color and luminosity, what would the sky look like from dawn to dusk?

Oh, and don't bring up the different lifespans because that is NOT what I'm asking.

• Luminosity is going to depend on the star's age. Commented Apr 25, 2021 at 15:36
• Color is a sensation. It exists in the mind. It is not a physical quantity; it does not exist in nature. We cannot tell anything at all about the colors perceived by an alien species living on an alien planet revolving around an alien star. (Ah, and our Sun is not yellow. It is white with a very very very slight yellow tinge. The same would go for a "blue" star -- it would be white, with a very very very slight blue tinge. Only a red star can be truely red, but then if it were as small in the sky as our Sun it would be so much less luminous that the sky would appear black.) Commented Apr 25, 2021 at 16:20
• @JohnWDailey If the star has a different color than the Sun, the star will have a different surface temperature than the Sun. If the star has a different surface temperature than the Sun, each unit of surface of that star will emit a different amount of radiation than such a unuit of surfe of the Sun does. So if the star has the same angular diamter in the sky of a planet as the Sun does in the sky of Earth, that planet should have a different temperature than Earth, and may be far too hot or to cold for Earth like life. Commented Apr 25, 2021 at 19:19