On this day, in 1999, the first launch of the Zenit-3SL carrier rocket was carried out under the Sea Launch program. The launch was carried out in test mode with the DEMOSat demonstration satellite as a payload. In October of the same year, the first commercial DirecTV satellite was launched into orbit by the Zenit-3SL launch vehicle.
Sea Launch is a transnational project, which included the American corporation Boeing, the Russian rocket and space corporation Energia, the Norwegian shipbuilding company Kvaerner, as well as the Ukrainian enterprises YUZHMASH and Yuzhnoye Design Bureau named after M.K. Yangel ".
The idea of the project was to deliver the launch vehicle by sea to the equator, where the best conditions for launching into space are.
In the history of world cosmonautics, there has already been a similar project - the Italian Space Center Luigi Brogli (San Marco). It was built from two recycled oil platforms that were based in the Indian Ocean. The cosmodrome was used in 1964-1988 for the launches of the American Scout light launch vehicle.
The main difference between Sea Launch and the San Marco project was that the Odyssey platform is not anchored at a certain point of deployment, but can move. In addition, the Italian spaceport was limited in payload. The Scout launch vehicle carried a payload of up to 68 kg, while the Zenit-3SL launch vehicle could launch about 6 tons of payload into a low reference orbit.
Technically, Sea Launch included the Odyssey launch platform with an information communication and launch device, a Zenit-3SL medium-class launch vehicle, the Sea Launch Commander assembly and command ship, and a land base in the port of Long Beach (California).
The Zenit-3SL launch vehicle was specially designed for the Sea Launch project. It was created on the basis of the two-stage flagship launch vehicle Zenit-2. The main advantages of Zenit-3SL are the implementation of fully automatic, without the participation of people, preparation for launch, the versatility of the complex, which made it possible to carry out operational and mass launches of commercial and scientific spacecraft, the ecological cleanliness of the launch vehicle, which excluded environmental pollution by traditional harmful fuel components (they were replaced by the oxygen-kerosene fuel pair), which is important when launching from the ocean and increasing their number.
The Zenit-3SL launch vehicle is a development of the Yuzhnoye design bureau. The first and second stages of the rocket were manufactured at Yuzhmash. In fact, Yuzhmash produced the Zenit-2SL launch vehicle, which was transformed into a three-stage Zenit-3SL already on board the assembly-command vessel by adding a booster block as a third stage.
The Odyssey offshore platform was created on the basis of an oil production platform built in Japan in 1982-1984. In 1996-1997, the platform was re-equipped at the Rosenberg shipyard (Norway) specifically for the Sea Launch project.
The Sea Launch Commander was built specifically for the Sea Launch project by Kvaerner Govan Ltd. in 1997. The equipment of the vessel made it possible to carry out a comprehensive test of the launch vehicle and the upper stage, refueling the upper stage with low-boiling propellants and gases, as well as the final assembly of the launch vehicle.
The launches were carried out from the Pacific Ocean, near Christmas Island, at the point with coordinates 0 ° 00 'n.d. 154 ° 00 'W from 1999 to 2014. A total of 36 launches were carried out, of which 33 were successful.
Now in the world there is not a single functioning sea spaceport.
In 2019, at the initiative of Yuzhmash, the National Bank of Ukraine issued a commemorative coin dedicated to the 20th anniversary of the world's first launch of Zenit-3SL launch vehicle from a floating launch platform as part of the Sea Launch international project.