Mercury (planet)
Mercury, also known as Sol I, was the first planet of the Sol system.

Location 
In the late 19th century, the orbit of Mercury was depicted on a German map of the inner system. ( opening credits)

In 2024, the position and orbital path of Mercury were depicted on a map of the Solar System, which was seen at the gala held for the Europa Mission astronauts. ()

In 2254, the orbit of Mercury was depicted on a map of the inner system, which was stored in the  library computer. This was one of the records scanned by the Talosians. ( 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. ( production art)

History 
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. ( okudagram)

In 1969, the  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. ()

Mercury was featured in an amusing story a holographic Doctor Stephen Hawking told his holographic poker partners  and Sir  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. ()

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." ()

Appendices

Background information 
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 , which was later cut, for , 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. 

According to the , Mercury orbited Sol at a distance of about 58 million kilometers, with day-side temperatures that could go as high as 430 °Celsius.

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  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 .

Apocrypha 
In William Shatner's  Captain's Glory, Mercury was home to a research facility, stated to be one of the oldest outposts in the Sol system.

External links 
 
 

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Planets
Sol system
The Adventures of Captain Proton