Those of us who know comics know that Superman gets his powers under the energies of a Yellow Spectrum Sun.
Red Suns deny him these energies.
But Astronomy teaches of of other stars.
There are five star colors: blue, white, yellow, orange, and red.
What effect do these other stars have on the Last Son of Krypton?
I remember reading a comic from long ago that said a red Sun turns Kal-el into the King of the Ants. With feelers, yet.
Blue sun - Ramps up his powers and gives him a few new ones
Red sun - doesn’t charge him
Yellow sun - powers
Orange sun - charges half as fast
Green sun - removes powers but gives him telekinesis and telepathy
White sun - God Superman
Dammit! I misremembered, it’s red Kryptonite not red sun. Still…
Based on the new Supergirl film, green sun = very bad to the point of being potentially deadly. But I have no idea if this is something they came up with for the film or if there’s precedent in the comics.
Red kryptonite does whatever the writer of that issue felt was going to advance the plot.
Versatile, huh?
There aren’t any green stars.
There aren’t any Kryptonians, or red Kryptonite, either. 
Wait - are you saying that Oa isn’t real?
What if it’s actually a red star but you’re colorblind?
What if Superman were exposed to gamma rays??!
William Herschel knew immediately that he’d discovered a new planet (Uranus) in 1781 precisely because it was green.
(Oddly enough, he wanted to name it King George’s Star.)
They thought they had discovered a new element due to a 530.3 nm emission line in the Sun’s spectrum, but it turned out to be highly ionized iron.
I think you’re confusing things a bit.
In Action Comics #296 coverdated January 1963 Superman deliberately exposes himself to Red Kryptonite (not a Red Sun) to give himself an ant’s head so he can communicate with giant invading red ants. (Red Kryptonite is Green Kryptonite that passed through some interstellar cloud and causes weird temporary effects on Kryptonians. Superman and his crowd have noted the effects of different pieces of Red Kryptonite, and keep a collection of these in lead containers – which blocks the radiation – so they can make use of these effects.)
I have a suspicion that this episode was inspired in part by Ralph Milne Farley’s Radio Planet series of stories, and in particular the 1950s comic adaptation of them that probably influenced the creation of Marvel’s Ant Man, who had first appeared as the character in September 1962. In other words, DC rushed their own version of Superman as Ant Man into a comic as soo n as Marvel introduced the character.
The Science Of covers the entire history of green stars in DC lore.
I remember in the 2025 Superman movie, his cousin Kara says she’s going to a planet with a red star so that she can get drunk.
Yeah. That’s because Kryptonians lose their “super” status when they go to a planet under red sun, according to Silver Age DC continuity. So they can get hurt and also be affected by drugs. If Superman wanted to get high on weed he’d have to go to a red sun world.
I wrote about it in another thread, but the planet Uranus was almost named Herschel.
It’s funny that DC Comics really liked to give special significance to the colors of things. The different Lantern Corps groups, the color of suns, the color of Kryptonite. Rainbow Brite would have fit in pretty well there. Heck, Superman has had rainbow powers before.
They really should do a sponsorship with Skittles at some point.
I imagine it has to do with the colorful medium of comic books, and DC in particular liked their very bright, colorful aesthetics.
Yeah, I corrected myself in Post #4.