The Coast Guard set fire to the oil that's leaking from that exploded rig in the Gulf of Mexico.

It's a last-ditch effort to contain the oil slick before it hits marshlands off the coast of Louisiana.

"When you can get oil ignited, it is an absolutely effective way of getting rid of a huge percentage of the oil. I can't overstate how important it is to get the oil off the surface of the water," Greg Pollock, with the oil spill division of the Texas General Land Office, said.

The fire is not expected to cause any damage to sea turtles or marine mammals in the area.

Meanwhile crews are still trying to use underwater robots to stop the leak that's 5000 feet below, on the ocean floor.

It's leaking about 42,000 gallons of oil into the Gulf every day.

Officials estimate the cost of the disaster could rise above $1 billion.