Moonbase Alpha: That time NASA made a meme video game

Kerbal Space Program has tons of mods that add realism, including a "realism overhaul" and a "Real Solar System" mod that also adds a realistic sky box

Spacewar! Basically the first graphic video game had an accurate star field.

[The] early version also contained a randomly generated background star field, initially added by Russell because a blank background made it difficult to tell the relative motion of the two spaceships at slow speeds.[2] The programming community in the area, including the Hingham Institute and the TMRC, had developed what was later termed the "hacker ethic", whereby all programs were freely shared and modified by other programmers in a collaborative environment without concern for ownership or copyright, which led to a group effort to elaborate on Russell's initial Spacewar! game.[4][13] Consequently, since the inaccuracy and lack of realism in the starfield annoyed TMRC member Peter Samson, he wrote a program based on real star charts that scrolled slowly through the night sky, including every star in a band between 22.5° N and 22.5° S down to the fifth magnitude, displayed at their relative brightness. The program was called "Expensive Planetarium"—referring to the high price of the PDP-1 computer compared to an analog planetarium, as part of the series of "expensive" programs like Piner's Expensive Typewriter—and was quickly incorporated into the game in March by Russell, who served as the collator of the primary version of the game.[2][4][7]