Kosmos 1761 (Russian: Космос 1761 meaning Cosmos 1761) is a Soviet US-K missile early warning satellite which was launched in 1986 as part of the Soviet military's Oko programme. The satellite is designed to identify missile launches using optical telescopes and infrared sensors.^[2]

Kosmos 1761

Mission type	Early warning
COSPAR ID	1986-050A
SATCAT no.	16849
Mission duration	4 years[1]
Spacecraft properties
Spacecraft type	US-K[2]
Launch mass	1,900 kilograms (4,200 lb)[3]
Start of mission
Launch date	5 July 1986, 01:16 (1986-07-05UTC01:16Z) UTC
Rocket	Molniya-M/2BL[2]
Launch site	Plesetsk Cosmodrome[2][3]
Orbital parameters
Reference system	Geocentric
Regime	Molniya[2]
Perigee altitude	615 kilometres (382 mi)[4]
Apogee altitude	39,739 kilometres (24,693 mi)[4]
Inclination	62.9 degrees[4]
Period	717.78 minutes[4]

Kosmos 1761 was launched from Site 43/4 at Plesetsk Cosmodrome in the Russian SSR.^[5] A Molniya-M carrier rocket with a 2BL upper stage was used to perform the launch, which took place at 01:16 UTC on 5 July 1986.^[3] The launch successfully placed the satellite into a molniya orbit. It subsequently received its Kosmos designation, and the international designator 1986-050A.^[3] The United States Space Command assigned it the Satellite Catalog Number 16849.^[3]