The world may have narrowly averted a serious nuclear accident in February when US scientists managed to get a deposit of enriched uranium out of Chile in the midst of a massive earthquake, MSNBC's Rachel Maddow told viewers Tuesday night.

Maddow reported on revelations in a Time magazine article that US officials were secretly engaged in removing from the country 40 pounds of enriched uranium -- the material needed for nuclear weapons and nuclear power generation -- when the 8.8-magnitude quake struck.

The earthquake occurred barely 12 hours after US and Chilean scientists had secured the uranium in special containers lined with eight inches of lead and steel. Had the uranium been unsecured at the time of the quake, there would have been a real risk of a nuclear incident. Forty pounds of uranium is enough to take "part of a large city," Maddow reported.

With the quake having destroyed the port where the uranium would be loaded onto two US ships, the scientists scrambled overnight to find an alternative route to get the uranium out of Chile, finally settling on another port, 50 miles away from the original.

The scientists moved the uranium in a "dark-of-night convoy through ravaged countryside with no electricity," Maddow reported. At the port, another close call ensued when one of the cranes loading the uranium onto a US ship malfunctioned and sent the uranium swinging overhead, before it was brought under control.

Maddow reported that the uranium -- which reportedly was being used as part of Chile's nuclear energy program -- ended up in South Carolina, where it was processed into less dangerous nuclear fuel.

"Much of the uranium around the world is very loosely guarded, and that is an enormous threat," reporter Ron Suskind told Maddow. "That is why the Obama administration has stepped up, and to be sure they've gone beyond the Bush administration quite dramatically."

President Obama hosts the heads of 47 countries in Washington this week for a nuclear security summit, the largest gathering of world leaders on US soil in more than half a century. Ahead of that conference, Ukraine announced it would be getting rid of its stockpile of enriched uranium, left over from when the country hosted Soviet nuclear weapons.

"Forty-seven nations coming to the US saying we need to solve this problem -- that is an enormous step forward," Suskind said.

Maddow noted that last year Obama announced a goal of securing the world's loose nuclear materials within four years.

"Everybody thought that health reform was going to be President Obama's lasting presidential legacy," Maddow said. "Health reform, I'd like to introduce you to your very dramatic international match."

This video is from MSNBC's The Rachel Maddow Show, broadcast April 12, 2010.

Watch this video on iPhone/iPad