Gorizont 33

Gorizont 33 (Russian: Горизонт 33 meaning "Horizon 33"), also known as Gorizont 45L was a Russian communications satellite operated by Kosmicheskiya Svyaz. It was the last satellite to be launched as part of the Gorizont constellation. Constructed by NPO Prikladnoi Mekhaniki, it was based on the KAUR-3 satellite bus. Its launch was contracted by Khrunichev, using a Proton-K/Briz-M carrier rocket. The launch occurred at 02:59 GMT on 6 June 2000 from Site 81/24 at the Baikonur Cosmodrome.

Gorizont 33

Mission type	Communication
Operator	Kosmicheskiya Svyaz
COSPAR ID	2000-029A
SATCAT no.	26372
Mission duration	Planned: 3 years Achieved: 8 years
Spacecraft properties
Bus	KAUR-3
Manufacturer	NPO-PM
Launch mass	2,300 kilograms (5,100 lb)
Start of mission
Launch date	6 June 2000 (2000-06-06)
Rocket	Proton-K/Briz-M
Launch site	Baikonur 81/24
Contractor	Khrunichev
Orbital parameters
Reference system	Geocentric
Regime	Geostationary
Longitude	145° East

This was the first successful launch of a Proton with a Briz-M upper stage, and as the previous Proton/Briz-M launch failed during the second stage burn, the first firing of a Briz-M in flight. The Proton itself flew with uprated engines, increasing its payload capacity ahead of the launch of Zvezda a little over a month later. The launch was conducted as a test flight of the Proton, and the satellite would not have been considered a significant loss if it had not reached orbit.

Following its launch and on-orbit testing, it was placed in geosynchronous orbit at 145° East, from where it provides communications services to Russia. It carried seven transponders, and had an expected on-orbit lifespan of three years. Its stabilisation system failed in May 2008, leaving the satellite drifting at a rate of 0.3 degrees West per day, eight years after it had been launched.