Deepwater Horizon

Former offshore oil drilling rig

Deepwater Horizon was an ultra-deepwater, dynamically positioned, semi-submersible offshore drilling rig owned by Transocean and operated by the BP company. On April 20, 2010, while drilling in the Gulf of Mexico at the Macondo Prospect, a blowout caused an explosion on the rig that killed 11 crewmen and ignited a fireball visible from 40 miles (64 km) away. The fire was inextinguishable and, two days later, on April 22, the Horizon collapsed, leaving the well gushing at the seabed and becoming the largest marine oil spill in history.

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