A chunk of Mifflin, the meteorite that lit up the sky in April (photo by Jim Holstein, The Field Museum)
The meteor news just don't quit. Back in April reports flooded in from around the Midwest about a massive fireball lighting up the night sky. Now the meteorite that caused it has a name (Mifflin), a face, (see above), and a back story. Chunks of Mifflin now reside at the Field Museum, and curator Philipp Heck has helped conduct the analysis. He and his colleagues say Mifflin was once part of an asteroid that blew up in a celestial collision about 470 million years ago. Debris from that crash has been raining on earth ever since. Mifflin is made of some exotic-sounding stuff, like olivine, pyroxene. But those minerals are actually pretty common (high-quality olivine makes a peridot, a green gemstone). Asteroids and planets, after all, were created around the same time from more or less the same stuff.
When I spoke to Adler Planetarium astronomer Mark Hammergren for the most recent Clever Apes, he mentioned that media accounts often erroneously associate meteorite sightings with fires. I immediately thought of the April fireball, and rumors of tree fires around Wisconsin and elsewhere (in case you missed it, Hammergren explains that meteorites almost never ever start fires on the ground, and are usually cold when they hit earth). In any case, Mifflin made quite an impression on many people who saw it, including my friend Steve Baron, a former TV meteorologist, who on a one-in-a-billion chance saw this fireball from the window of an airplane. Crazy.