Sea Launch is a spacecraft launch service based on the principle that launches from the Earth's equator are the most fuel-efficient possible, utilizing the Earth's rotation to help accelerate a rocket to escape velocity. To launch a rocket from the equator without being dependent on any equatorial government or nation, the venture uses a self-propelled ocean platform located in the equatorial Pacific, the Ocean Odyssey, as the launch pad. The rocket and payload are assembled and carried to the platform by the Sea Launch Commander, which ports in Long Beach, California. The total cost of the project was reported as $583 million USD (US Dollars) in 1996, with $400 million USD in loans from Chase Manhattan secured around this time.
Sea Launch was founded in 1995, and is owned by a consortium of 4 companies; Boeing Commercial Space (United States, 40% ownership), Energia (Russia, 25%), Aker Solutions (Norway, 20%), and SDO Yuzhnoye (Ukraine, 15%). The first rocket launch was in 1999. The clients are all communications companies, like EchoStar, DirecTV, XM Satellite Radio, and PanAmSat. The satellites are inserted into geostationary transfer orbit, which consists of the satellite cycling between a point in low earth orbit (LEO) and geostationary orbit (GSO).
In its first decade of operation, Sea Launch successfully launched 30 rockets, with two failures. A failure on 30 January, 2007 resulted in the explosion of the rocket, fuel, and its payload on the launch platform, creating a massive fireball with a diameter of more than 1000 ft (300 m). A video clip of the launch failure can be seen on YouTube. Repair required docking the platform at a facility near CFB Esquimalt, just west of Victoria, British Columbia.
There are a variety of benefits to equatorial launches that Sea Launch exploits, aside from just the speed boost due to the planet's rotation. One is that there is no need for a fuel-consuming "plane change" to reorient a geostationary satellite with the zero degree orbit necessary to keep up with a point on the Earth's surface as it rotates. Another is greater safety for the surrounding area -- failed land launches have a risk of impacting populated areas. Yet another is the extremely low air and sea traffic in the area around the launch platform, making launch scheduling easier.
Interestingly, the Ocean Odyssey was not custom-built for the Sea Launch operation but actually began life as a prospecting platform built for the Ocean Drilling and Exploration Company by Sumitomo Heavy Industries.