K-496 Borisoglebsk is a Russian advanced Delta III SSBN nuclear submarine. On 21 June 2005 the vessel served as the launch platform for a missile carrying a payload containing a solar sail experiment, Cosmos 1. The submarine was based in the Russian Northern Fleet. In early December 2008 Borisoglebsk was decommissioned from the fleet and was getting ready to be scrapped.^{[3][needs update]}

History
Soviet Union, Russia
Name	Borisoglebsk
Laid down	23 September 1975
Launched	13 August 1977
Completed	30 December 1977
Decommissioned	December 2008
Fate	To be dismantled
General characteristics [1][2]
Class and type	Delta III-class submarine
Displacement	Surfaced: 10,600 tons Submerged: 13,700 tons
Length	155 m (509 ft)
Beam	11.7 m (38 ft)
Draught	8.7 m (29 ft)
Depth	Operational: 320 m (1,050 ft) Maximum: 400 m (1,300 ft)
Propulsion	Reactor system OK-700A (two VM-4S (2*90 MW) PWR) powering 2 steam turbines delivering 44,700 kW (59,900 shp) to 2 five-bladed fixed pitched shrouded propellers
Speed	Surfaced: 14 knots (26 km/h; 16 mph) Submerged: 24 knots (44 km/h; 28 mph)
Range	Unlimited, except by food supplies
Complement	40 officers, 90 enlisted
Armament	16 × RSM-50 R-29R "Vysota" missiles 4 × bow 533 mm (21 in) torpedo tubes 16 torpedoes (SET-65, SAET-60M, 53-65K, 53-65M)