It is a large flat oblong disk with 4 warp nacelles 2 above and 2 below. The ship has details recogniably borrowed fromt the Contitution class starship.
The Constellation class was designed in the 2280's to supplement the Constitution class starship. The Constellation was intended to be very like the Constitution but with longer range.
This is the reason for 4 Nacelles - the ship isn't any faster at warp than a Constitution class but uses her warp drives up at half the pace, allowing for long cruise durations.
The Constellations, like the Miranda class proved adaptable and robust designs. They remained in use for a long time.
By the time of TNG 2364, the Constellations are two generations out of date, but because Space is Really Big no ship that can still do useful work is retired.
Because Constellations spent a lot of time on the frontier, they got involved in a lot of "adventures", especially of the "strange new worlds" variety, and so they have become romanticized in Starfleet, not unlike the Constitution class.
Type: Cruiser (obsolete) Examples:
- USS Constellation - Rolled out by Captian Jerry LaSaille. Destroyed (Epiphany Trek That Thou Art Mindful), NX/NCC 1974
- USS Gettysburg - Active, NCC 38902
- USS Hathaway - Destroyed, NCC 2593
- USS Magellan - Destroyed, NCC 3069
- USS Stargazer - Retired, NCC 2893
- USS Victory - Active, NCC 97542
- USS Harrier - Retired Scrapped, NCC 45657
- USS Harrier  - A quantum duplicate of the first ship - Preserved at Starbase 600
- USS Harrier  - Yea, again. Given a Disodium refit for one trip, to get her crew home. Also preserved at Starbase 600
- USS Parneb, Lost 22XX, Recovered 239X, NCC-4255
Commissioned: 2283 - 2315, class being phased out of service
- Length: 231 m
- Beam: 135 m
- Height: 65 m
- Decks: 15
- Mass: 325,000 metric tons
- Crew: 520 (originally - the number of crrew has dropped over time.)
- 6 x Type VIII phaser bank
- 2 type 15 photon torpedo tubes with 200 rounds
- Standard shield system
- Standard Duranium hull.
- Standard level Structural Integrity Field
Warp Speeds TNG Warp Scale:
- Normal Cruise: 6
- Maximum Cruise: 8
- Maximum Rated: 8.6 for 12 hours.
Comparison: Galaxy Scale (Galaxy class = 1,000)
- Beam Firepower : 330
- Torpedo Firepower : 250
- Weapon Range and Accuracy : 750
- Shield Strength : 455
- Hull Armour : 675
- Strategic Speed : 350
- Strategic Range: 500
- Combat Maneuverability : 2,000
- Overall Strength Index : 333
- Diplomatic Capability : 300
- Expected Hull Life : 80 years
- Refit Cycle : Minor : 1 year
- Standard : 1 years
- Major : 10 years
The Constellation class was fielded during the 2280's as a modern counterpart to the Constitution class then in service. Like the Constitutions, the Constellation requirement issued in 2272 called for a vessel capable of long duration exploratory, scientific and diplomatic missions. The new ship was to be able to perform this role over the longer ranges called for now that the Federation had acquired new members beyond its previous borders.
A few Constellation class vessels remain in service; as is often the case with past-their-prime designs the ships are now used for rear echelon general support duties.
The Constellation class starship was kitbashed together in 1987 for the first Season of Star Trek, the next generation. The reason for this was that Picard's prior starship, the USS Stargazer was written as a Constution class Starship similar to the Enterprise as seen in the movies.
After the live action parts of the episodes were filmed, Gene Roddenberry changed his mind and mandated a different starship. Because Gene Roddenbery decreed it, the Constitution class ships were held to be retired, even though Miranda class starships are still seen. In 1991, the Enterprise-A made her last appearance in STVI.
The Hathaway model was kitbashed and named "Constellation Class" because that fit Geordi's visual mouth movements when he said the Stargazer was a Constitution class. LeVar Burton redubbed the line.