A rare "extraterrestrial mudball" rained on a small town

We could think of meteorites in the form of dry and dead pieces of space rock. But a mess of wet cosmic clay broke over a small town in Costa Rica last month, flooding the region with fragments of a rare type of meteorite.

The meteoroid as big as a washing machine illuminated the sky of Aquas Zarcas, Costa Rica, on April 23, while it was flying in smaller pieces. A fist – sized piece is smashed across the roof of a house, hitting some tables inside.

Although the meteorite looks like a normal stone, it is actually a rare carbonaceous chondrite, rich in organic compounds and full of water.

"Many carbonaceous chondrites are mud balls composed of 80 or 95% clay," Laurence Garvie, a research professor at Arizona State University, said in a statement. "Clays are important because water is an integral part of their structure."

Many scientists have rushed to get their hands on what could be fragments of the early solar system fallen from the sky.

"He trained in a lifeless environment, then was preserved in the cold and emptiness of space for 4.56 billion years, and then abandoned in Costa Rica," explained Garvie.

The last time that such a rain of carbonaceous chondrite fell on the ground dates back to 50 years ago, in 1969, researchers were so eager to recover the samples before the elements.

"These had to be picked up quickly and before it rained," Garvie explained. "Because they're mostly clay, as soon as these types of meteorites get wet, they break up."

More than 50 pounds of meteorites were collected in the area before the next rain, and ASU was part of the research institutions that bought samples from local collectors.

Meenakshi Wadhwa, director of the USS Meteorite Studies Center, said they could "contain the best preserved clues about the origin of the solar system."

"This new meteorite represents one of the most scientifically significant additions to our wonderful collection in recent years," Wadhwa said.

Samples from the Costa Rican Meteor are on display at the Center's collection on the ASU campus in Tempe, Arizona.