FMNH Collection Data:
Classification: Carbonaceous chondrite (CV3)
Specimen number: FMNH ME 2639, sp. 22
Specimen mass: 710.8 gram
A huge fireball lit up thousands of square miles of Northern Mexico and Southwestern United States after midnight on February 9, 1969. The Allende meteorite shower spread over more than 150 square kilometers and yielded thousands of carbonaceous chondrite fragments with a total mass of 2 metric tons. Allende contains abundant chondrules, and large Calcium-Aluminum-rich Inclusions (CAIs) embedded in a dark matrix. The CAIs are the Solar System’s first solid condensates and are 4.567 billion years old. The matrix contains hundreds part per million nanodiamonds, some of which are presolar.
Image/animation: © 2011 The Field Museum.