Meteorite chunks from Mars fell over Morocco last summer — the first time in 50 years such an event has occurred, scientists confirmed Tuesday.

It is only the fifth time newly fallen Martian rocks have been confirmed chemically by experts. Known Martian meteorite falls have happened only once every 50 years or so — 1815 in France, 1865 in India, 1911 in Egypt and the last in 1962 in Nigeria.

Scientists and collectors were celebrating the find.

"It's Christmas in January," said former NASA sciences chief Alan Stern, director of the Florida Space Institute at the University of Central Florida. "It's nice to have Mars sending samples to Earth, particularly when our pockets are too empty to go get them ourselves."

Sightings of the meteorite chunks falling in North Africa were reported and captured on video last July but the rocks weren't discovered on the ground until the end of December.

The meteorites were named Tissint by the International Society for Meteoritics and Planetary Science, which is the official group of 950 scientists that confirms and names meteorites.

The organization, which includes some NASA scientists, certified that 6.8 kilograms of the meteorite came from Mars, with the biggest rock weighing nearly one kilogram.

University of Alberta meteorite expert Chris Herd, who heads the committee that certified the discovery, said the first thing he would do with the rocks would be to rinse them with solvents to try to get rid of earthly contamination and to see what carbon-based compounds are left.

Scientists can identify meteorites from Mars because of what they know about the Martian atmosphere based on numerous probes sent there. The chemical signature of the rocks and the Martian air match, said Tony Irving of the University of Washington.

Another clue is that because Mars is geologically active, its rocks tend to be much younger — millions of years old instead of hundreds of millions or more — than those from the moon or asteroids.

Most of the known Martian rocks on Earth have been around for centuries or longer and have been found in Antarctica or the desert. They look so similar to dark Earth rocks that if they fell in other places, such as Maryland, they would blend right in and never be discovered.

Astronomers theorize that millions of years ago something big smashed into Mars, sending fragments hurtling through the solar system, some of which occasionally fall on Earth.

Most other rocks from Mars are tainted with Earth materials and life because they sat around on Earth for millions of years, or at least decades, before they were discovered. The new rocks, on the other hand, while still probably contaminated because they have been on Earth for months, are purer.

The rocks are fetching big bucks because they are among the rarest things on Earth — rarer even than gold. Scientists at NASA, museums and universities are scrambling to buy or trade them.

"It's incredibly fresh. It's highly valuable for that reason," said Carl Agee, director of the Institute of Meteoritics and curator at the University of New Mexico. "This is a beauty. It's gorgeous."

Meteorite dealer Darryl Pitt said he is charging $11,170 to $22,845 Cdn an ounce and has sold most of his supply already. At that price, the Martian rock costs about 10 times as much as gold.

With files from The Associated Press