In 2254, the orbit of Mercury was depicted on a map of the inner system, which was stored in the USS Enterprise library computer. This was one of the records scanned by the Talosians. (TOS: "The Cage" production art)
In 2267, the orbit of Mercury was depicted on "Chart 14A: The Sol System", which was stored in the Enterprise library computer. This chart was scanned by the probe Nomad in auxiliary control. (TOS: "The Changeling" production art)
Before the invention of the telescope, Humans discovered Mercury in the night sky. This planet was explored by unmanned NASA spacecraft in the twenty-two years that followed the launch of Sputnik in 1957. (TNG: "Loud As A Whisper" okudagram)
In 1969, the USS Enterprise passed Mercury as it attempted a slingshot effect around Sol in an effort at returning to 2267. When the Enterprise passed this innermost planet, the gravitational pull of the star increased. (TOS: "Tomorrow is Yesterday")
Mercury was featured in an amusing story a holographic Doctor Stephen Hawking told his holographic poker partners Albert Einstein and Sir Isaac Newton and Data. He said that "in that frame of reference the perihelion of Mercury would have precessed in the opposite direction!" Albert Einstein found this "a great story"; Sir Isaac Newton, however, did not understand the joke. (TNG: "Descent")
In the The Adventures of Captain Proton holoprogram series, Mercury was controlled by Doctor Chaotica. When he tried to conquer Earth, he claimed that those who oppose him "will face a dire fate as slaves in the mines of Mercury." (VOY: "Bride of Chaotica!")
|The Sol System|
|Mercury • Venus • Earth (Luna) • Mars (Deimos) • Asteroid belt • Jupiter (Io; Ganymede) • Saturn (Mimas; Rhea; Titan) • Uranus • Neptune (Triton) • Pluto|
According to Star Trek: Star Charts (p. 19; "United Federation of Planets I"), Mercury was classified as a B-class planet. This planet was a charter member of the United Federation of Planets in 2161.
In dialogue from the script, which was later cut, for Star Trek Nemesis, the Romulan planet Remus was compared to Mercury, in that both planets always have one side facing their primary which is incorrect as Mercury rotates three times for every two orbits it makes.
A number of labels seen on a holographic globe of the moon Delta 2 in fact belong to features of Mercury. Similarly, a display graphic created by G. Creative Productions Inc. for Star Trek Beyond but possibly not seen in it listed a number of technical characteristics of Altamid, which appear to have been copied from Mercury. The graphic can be seen here.