Standard orbit
Standard orbit, parking orbit, or a combination of the two, was the orbit assumed by a starship to maintain its relative position or altitude over a planet's surface, from where general orbital scans were performed, communications would be established, or individuals could be beamed to and from the surface. When the same starship orbited a space station, this was called standard station orbit. ()

Examples 
The following were locations that were orbited from "standard orbit" or "parking orbit":

The  attempted to enter standard orbit of a Romulan planet when it was hit by a mine. ()

The  over  in an alternate 2258. ()

The  visited the following locations where it entered standard orbit:
 Delta Vega ()
 Exo III ()
 Tantalus V ()
 Eminiar VII ()
 Later, when the Enterprise was under attack from the planet, Spock ordered Lieutenant Commander Montgomery Scott to "orbit out to maximum phaser range and stand by for further orders." 
 Omicron Ceti III ()
 Organia ()
 Following the Enterprises hastened departure, "eight space vehicles have assumed orbit around our planet." 
  ()
 Gamma Canaris N ()
 Capella IV ()
 Pollux IV ()
 Gamma Hydra IV. ()
 During this particular mission Captain Kirk ordered Lieutenant Hikaru Sulu to "increase orbit to 20,000 perigee," twice. When Sulu questioned if he wanted to increase another 20,000, Spock inquired as to the present position, to which Sulu stated "orbiting at 20,000, sir." Following the clarification, Kirk wished to maintain their present position. 
 Gamma II and Triskelion. ()
 Sigma Iotia II ()
 892-IV ()
 Arret ()
 Ekos ()
 Following an attack from the planet's surface, the Enterprises orbit was adjusted to maximum orbit, and "out of range of their detection range." 
 Starbase 6 and Alpha Carinae II. () 
 During the M-5 drill, while taking the Enterprise into standard orbit of Alpha Carinae II, the M-5 computer was instructed to "handle its approach, the orbit, and then to analyze data regarding landing party recommendations." 
 Melkotian planet ()
 Triacus ()
 Motherlode and the rock creature planet. ()

The  at Ceti Alpha V in 2285. ()

The  at the Genesis Planet in 2285. ()
 Captain J.T. Esteban instructed the helm to "execute standard orbital approach", which was acknowledged with "Standard orbit. Aye sir."

The  at Nimbus III and Sha Ka Ree in 2287. ()

The  visited the following locations where it entered standard orbit:
 Deneb IV ()
 Upon arrival, Captain Jean-Luc Picard inquired if they had clearance to enter orbit, which was acknowledged that they had "into the standard parking orbit." 
 Ligon II ()
 Jaradan planet/Torona IV ()
 Omicron Theta ()
 Upon arrival Captain Jean-Luc Picard instructed the conn to "continue on into close parking orbit."
 Velara III ()
 Relva VII ()
 According to Lieutenant junior grade Geordi La Forge, to Commander Dexter Remmick, "There's nothing much to see here, Commander. We're in a standard orbit, and the station has to be manned even if it's just routine." 
 Minos ()
 Ornara ()
 Vagra II ()
 Vandor IV ()
 Earth ()
 'aucdet IX and Science Station Tango Sierra. ()
 When the Enterprise later arrived at the science station, the conn was instructed to enter "standard station orbit", which was acknowledged with "Aye, sir, standard orbit."
 Ramatis III and Solais V. ()
 Klavdia III and Daled IV. ()
 Gagarin IV ()
 Gamma Hromi II ()
 Koinonian homeworld ()
 Nelvana III ()
 Devidia II ()
 After initially entering orbit, the ship's sensors detected "an unusual temporal disturbance on a small area of the planet's surface," located at "forty two degrees seven minutes north by eighty eight degrees declination east." The ship readjusted its position and was put "in a standard orbit above those coordinates."  
 Ligos VII ()
 Ruah IV ()
 Renegade Borg planet ()
 Kalla III ()

The  visited the following locations where it entered standard orbit
 L-S VI ()
 Once scans were initiated, it was noted that the planet had "a lot of seismic activity down there, possibly volcanic in origin," before deciding to "[Move] into synchronous orbit." 
 The former Hur'q planet. ()

The  at Callinon VII in 2371. ()

Damar's attack ship at Cardassia Prime in 2375. ()
 Upon reaching the planet, orbital traffic control requested the ship/crew's security clearance, after which they were cleared for entry into standard orbit. 

The  visited the following locations where it entered standard orbit
 Augris' homeworld ()
 Silver Blood homeworld ()

Background information 
In the episode , according to the , the Enterprise-D was in a standard orbit over the planet Haven. 

According to the Star Trek Writers/Directors Guide (third revision, , p. 24):

The Enterprise usually takes up what we term "standard orbit" around a planet. Depending on a number of conditions or needs, this distance can be from one to seven thousand miles high. Our vessel was constructed in space and has never felt the solidity of the surface of a planet. In other words, it doesn't land, it stays in orbit.

According to the :
The term "standard orbit" was used as an ingenious means of allowing the captain to give a technical-sounding command when the ship entered orbit, without having to bore the viewer with tedious details of orbital inclination, apogee, perigee, and orbital period. It was at one point thought that standard orbit would be synchronous, allowing the ship to remain stationary over a single point on a planet's surface, but a visual-effects shot of the ship, motionless over the planet, would not have been dynamic, thereby lacking dramatic value. Moving the ship was, therefore, a conscious decision by the show's producers. Even when the ship was required to "hover," some slight movement was shown so that the image wouldn't be static.

According to the Star Trek: Voyager Technical Manual (p. 26):
Standard orbit: When Voyager orbits a planet, it generally assumes what is called STANDARD ORBIT. For a Class M (Earth-type) planet, this is often a synchronous orbit at about 35,000 kilometers altitude.

External link 
 

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