Close Window
Gold Country Meteorites: Earth Image of the Week May 4, 2012
Last image from Envisat
CM type carbonaceous chondrite fragments found in California that were part of a “minivan size” meteor that exploded over the western U.S. on Earth Day.
Some of the Solar System’s oldest matter fell to Earth over Northern California’s “Gold Country” shortly after dawn on April 22 — Earth Day.

The primordial fragments that rained from the sky were remnants of a bright fireball that had just seconds earlier lit up the sky from western Nevada to the Sacramento Valley.

It also produced a sonic boom that was heard from northern Arizona and Nevada to the foothills of the Sierra Nevada.

And just like the miners who rushed to the same area after gold was discovered at nearby Sutter’s Mill in 1848, meteorite collectors from far and wide soon arrived on their own astronomical treasure hunt.

And what they found scattered on the ground around Coloma, California, were some of the rarest and most expensive kinds of meteorites ever found.

Composed of a rock known as CM-type carbonaceous chondrite, they comprise less than 1 percent of all meteorites that fall to Earth, according to Bill Cooke of NASA’s Meteoroid Environment Office at the Marshal Space Flight Center in Huntsville, Alabama.

“It’s the rarest of the rare. It’s older than the sun,” meteorite hunter Robert Ward told reporters.

The fragile black rocks mainly burn up when entering Earth’s atmosphere. They contain a lot of carbon and organic materials such as amino acids, which some believe brought the first building blocks of life to the planet.

The meteorites are invaluable to science but they can also fetch $1,000 a gram on the open market.

Local resident Brenda Salveson found one carbonaceous chondrite stone the size of a spool of thread that weighed 17 grams.

Full story and image: NASA