Vulcan system
The Vulcan system, or 40 Eridani, was an inhabited star system located in the Alpha Quadrant. This was a trinary star system. Several planets, including  and , orbited the star 40 Eridani A. Neighboring the Andorian system, it was located sixteen light years from the Sol system. (; ; )

In 2256, Vulcan was labeled on the star chart "Alpha/Beta Quadrant Overview" in the ready room aboard the . ()

In 2257, during the first , this star's system was near the front line. ()

In 2258, the system's location was labeled on a star chart seen on the main viewscreen of the . ()

That same year, in the alternate reality, Delta Vega was the location of a Starfleet outpost. That year, Nero destroyed the planet  by creating a small black hole in its core. ()

In 2259, the location of this system was labeled on a stellar cartography chart that was seen on the 's ready room viewscreen. This system's symbol had a blue color, indicating it's affiliation with the Federation. () 

In 2293, the location of Vulcan in the Milky Way Galaxy was labeled in a star chart that was in Captain James T. Kirk's quarters aboard the . (, okudagram)

In 2399, the location of 40 Eridani was labeled on a Federation star chart that was in Fleet Admiral Kirsten Clancy's office at Starfleet Headquarters. This system was in Federation space. ()

See also 
 40 Eridani A Starfleet Construction Yards
 Vulcan space

Appendices

Background information 

A picture of a star chart supposedly used for  was tweeted by Ted Sullivan on November 28, 2017. According to this map, the star Vulcan was also known as 40 Eridani A. 

The original theatrical edit of  depicted four large orbs in the Vulcan sky. They were removed in the DVD release of  and replaced by an orange sky. According to , the additional planets were removed for the reason that the scene took place during daytime, so a night sky was not appropriate, and they were elements that distracted the viewer from a scene intended to take place on a far-off monastic temple. Vulcan in and of itself was considered to be interesting enough without cluttering the sky with these planets.

In the  episodes , , and , celestial bodies were seen from the surface of Vulcan. For the first time, in , celestial bodies near to Vulcan were seen in space.

According to Star Trek: Star Charts (p. 58), T'Khut was the name of Vulcan's twin planet that was visible from the planet's surface. T'Khut was classified as a G-class world, and had one moon. The Vulcan system also known as the 40 Eridani A System or Omicron2 Ceti System was a trinary star system. 40 Eridani A had a spectral type of K1V with an absolute magnitude of 6.0. 40 Eridani B had a spectral type of AVII with an absolute magnitude of 11.2. 40 Eridani C had a spectral type of M4V with an absolute magnitude of 12.3. The distance between A and B was 400 au; the distance between B and C was 44 au. The orbital period of this system was 248 years.

According to the Stellar Cartography: The Starfleet Reference Library ("Stellar Cartography", pp. 22-24 & 34), the Vulcan system was the 40 Eridani A system. The 40 Eridani system was known to the Vulcans as Nevasi. The primary star, 40 Eridani A (Nevasi A), was class K. The innermost planet was a rocky class B planet named Ket-Cheleb. Vulcan (T'Khasi) was in a co-orbital relationship with the class G planet T'Khut ("the Watcher"), which had one moon named T'Rukhemai ("the Eye of the Watcher"). The icy planetoid Delta Vega was located in the outer asteroid belt. The two companions of 40 Eridani A, 40 Eridani B (Nevasi B) and 40 Eridani C (Nevasi C), were a white class A4 dwarf and a red flare class M4 dwarf, respectively.

There had been, however, no direct canonical reference of the Vulcan system being the 40 Eridani system before it was canonized in the Star Trek: Picard episode "Maps and Legends". In  and , Vulcan was mentioned as being slightly over sixteen light years from Earth, the same distance between Earth and 40 Eridani A. According to text commentary by Michael and Denise Okuda for  on the ENT Season 4 DVD, the possibility of Vulcan being located in the 40 Eridani system originated from a suggestion by novelist James Blish. When three astronomers (Sallie Baliunas, Robert Donahue, and George Nassiopoulas) who had been studying the system at Mount Wilson Observatory published a letter stating that the star "40 Eridani A could support a planet with Earth-like life" and that it would "have the Sun's brightness for a planet fifty million miles away", they theorized that Vulcan could be in orbit of this star, a theory Gene Roddenberry himself supported by signing their letter, according to Sky & Telescope, 1991 July.

In a tweet from  first assistant art director Timothy Peel, there was an image of the Vulcan system, which according to him was seen at the console holding the astrogator of the . The system was depicted as a three-planet system, containing the planets 40 Eridani A 1, T'Khut, and Vulcan. The latter two planets were in a co-orbital relationship. T'Khut was orbited by an unnamed moon. Past Vulcan and T'Khut, there was an asteroid belt. Lying nearby, there were the stars 40 Eridani B and 40 Eridani C, which, too, had a co-orbital relationship.

External links 
 
 
 

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fr:Système vulcain
ja:ヴァルカン星系
nl:Vulcan systeem
Star systems
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