(covers information from several alternate timelines)
In 2370, some Nova-class starships were constructed in the Sol system at the Utopia Planitia Fleet Yards, around stardate 47007.1. USS Equinox was constructed and launched at this time. (VOY: "Equinox", "Equinox, Part II" dedication plaque)
Schematics of the Nova-class were contained in the 31st century database kept by temporal agent Daniels aboard the Enterprise NX-01. They were viewed by Captain Jonathan Archer and Lieutenant Malcolm Reed who accessed his database in 2151. (ENT: "Shockwave") They were later viewed by Archer and T'Pol in Daniels' database the following year. (ENT: "Future Tense")
In an alternate 2404, a refit of the Nova-class was in use. The interior of the ship was almost the same, however, the exterior had a number of changes. The refit also had superior tactical firepower and shield strength to that of its predecessor. (VOY: "Endgame")
The Nova-class was designed as a science and scout vessel, intended for short-term planetary research and analysis. It is not typically suitable for combat operations. The Nova design has a maximum speed of warp 8 and approximately eighty crewmembers. One unique feature of the Nova-class is its Waverider shuttle, which is located in a special docking port on the ventral side of the primary hull, similar to that of the Aeroshuttle on the Intrepid-class.
The Nova-class had a design similar to that of an Intrepid-class starship, though smaller in size. It consisted of a saucer section with a curved triangular shape. The secondary hull was directly attached to the underside of the saucer with two warp nacelles.
Unlike some starship designs, the Nova-class only featured one impulse drive, located at the aft end of deck 2 aligned center to the ship.
Though Novas were science vessels, they had a wide assortment of weaponry, allowing the vessel to handle many threats on its own. It was equipped with eleven strategically-placed phaser arrays: eight on the saucer and three on the secondary hull, two forward-facing photon torpedo launchers at the bow of the saucer opposite of the secondary deflector, and one aft-facing launcher.
In order to prevent space debris and objects from colliding and damaging the vessel, Nova-class vessels, like other Starfleet vessels, were equipped with a navigational deflector at the bow of the secondary hull. If the main deflector was damaged or disabled, a secondary deflector on the saucer could substitute the main deflector.
Like most Starfleet vessels, the Nova-class was also equipped with a deflector shield for defensive purposes. Shields on a Nova-class could be fully recharged after charging the shield emitters for 45 seconds. This task required the shields to be dropped. The shield grid itself was located along the secondary hull.
Though a small ship, the Nova class was able to accommodate the needs of the crew. This class of starship had eight decks.
- See: Nova class decks
The main bridge, located near the center of deck 1, was the command center for the ship. Despite the size of the ship, the spacious bridge allowed for the ease of movement between stations.
The central command area on the bridge was at the very center of the circular area in a submerged location. The captain's chair was starboard side, and the executive officer's was on the port side. Between them was a console built into the structure that provided a place for information dissemination, as well as operational command of the starship. Directly ahead of the command area and down into a further sunken area, was the conn.
The rest of the stations were located on the perimeter of the round bridge, including the master systems display behind the command seats and the main viewscreen in the standard frontwards position. Stations, such as tactical, were not stand-out stations due to the scientific nature of the design. When necessary, Tactical would usually be assigned to the forward, starboard side console just right of the main viewscreen.
Entryways to the bridge were located at the port and starboard sides on the upper level. The port door leads to the main turbolift while the starboard door leads to a corridor that accesses other sections of deck 1. Access to the captain's ready room was also located on port side.
Main engineering was located on deck 7. The Nova-class engineering section only spanned one deck, and featured four wall based engineering consoles and a warp core analysis console in front of the core itself. At the far end of the room was the warp core with a transparent floor and support railing around it. The core spanned from decks 5-8 and could be ejected from the bottom of the ship through an ejection hatch. The core could be accessed from either engineering or from the maintenance areas around the core.
Sickbay and science labs
Additionally, as a science vessel, the Nova-class was equipped with a number of specially-equipped science and research labs. The labs were similar to those found on an Intrepid-class vessel and served many purposes and supported numerous personnel. They featured a great number of work consoles to perform numerous tasks and had one main work console area in an alcove.
Auxiliary craft and cargo bays
Behind the main sickbay were the 2 shuttlebays. The aft-most shuttlebay's space doors are directly aft (similar to the Intrepid-class). The inner shuttlebay's doors open directly above.  An additional view of the secondary shuttlebay can be seen here (the aft-most black rectangle on the dorsal side of the ship).
In the saucer on deck 4, a short trip from the shuttle bays, was the aforementioned Waverider auxiliary craft, which was integrated into the Nova-class' hull. Spanning decks 2 and 3 in front of the shuttlebay were the main cargo bays which could also contained CMUs, used for transportation and repair purposes.
Additionally, like a majority of starships in the 24th century, Nova-classes were equipped with emergency escape pods, twenty in total; fourteen were located on deck 3, four on deck 1 and two on deck 2, all located in the saucer section. They were stored under hatches to permit both launch and retrieval.
Due to the size of this class, crew quarters were spartan, but provided all the standard needs for the crew. A majority of the quarters were standard crew quarters, though a number of them were larger for use by the senior staff. The majority of these larger quarters were located on decks 1 and 4, with slightly smaller ones located on decks 2 and 6.
- USS Nova (NCC-73515)
According to Star Trek: The Next Generation Technical Manual, the Nova-class is the successor of the Galaxy-class starship as the next primary explorer ship of Starfleet. Four different concept designs were presented on pages 177 and 178. The direction the actual Nova-class eventually followed was the down-sized ship with less internal volume that allowed each ship to be refitted for specific mission types and an angular-curvilinear shape designed to allow an enhanced utilization of warp energy.
One of the other designs that was not followed featured variable geometry pylons that ended up to be featured on the Intrepid-class. Another design featured an elliptical saucer section extended steeply toward port and starboard, a shape intended to enhance the peak transitional efficiency of a high-frequency warp envelope. This feature was eventually featured on the USS Enterprise-J. It was also stated that the USS Enterprise-E might end up being of this class, but a ship of the Sovereign-class was given the name. (VOY: "Caretaker"; ENT: "Azati Prime"; Star Trek: First Contact)
According to the Star Trek: Starship Spotter, the ship was equipped with only two cargo management units and two shuttlecraft. The phaser arrays were classified as Type X, the same as the Galaxy-class and Intrepid-class phasers. The ship had a mass of 110,000 metric tonnes.