said by dvd536 :

Launching from an oil drigging rig. what brainiac thought of that? why not just launch from the roof of a dynamite factory?

The Launch Platform—or LP—a former North Sea oil drilling platform, was refurbished at the Rosenberg Shipyard in Stavanger, Norway. The vessel is one of the largest semi-submersible, self-propelled vessels in the world at 436 feet long, about 220 wide, with an empty draft displacement of 30,000 tons, and a submerged draft displacement of 50,600 tons.

The Launch Platform provides accommodations for 68 crew and launch system personnel—including living, dining, medical and recreation facilities. It is equipped with a large, environmentally controlled hangar for storage of the Sea Launch rocket during transit, and with mobile transporter/erector equipment that is used to roll out and erect the rocket in launch position prior to fueling and launch. Special facilities onboard enable the storage of rocket fuels (kerosene and liquid oxygen) sufficient for each mission.

said by THZNDUP :

That ex-drilling platform was modified then moved to the Pacific. It wasn't used for drilling out there.