The pod should soon be on its way back down for reattachment to the preventer.

ECONOMIST: The Gulf oil spill

At that depth, a key piece of equipment is the blowout preventer, which weighs up to 300 tons and caps the well, holding back ultrapressurized oil deep in the Earth.

FORBES: On The Cover/Top Stories

At that depth, a key piece of equipment is the blowout preventer, which weighs up to 300 tons and caps the well, holding back ultrapressurized (15, 000 pounds per square inch) oil deep in the Earth.

FORBES: On The Cover/Top Stories