Meteorites

Buzzard Coulee

Buzzard Coulee is an ordinary (H4) chondrite that fell November 20th, 2008, in rural Saskatchewan, Canada.

The associated fireball was quite visible, and was witnessed by several; according to the Meteoritical Bulletin (MB 95):

"A bright fireball was widely observed across Alberta, Saskatchewan and Manitoba during late twilight on November 20, 2008. The fireball and subsequent dust trail, or shadows cast by the fireball, were recorded by all-sky and security video cameras establishing that its brightest portion occurred from 17:26:40 to 17:26:45 MST. The fireball traveled approximately north to south with an elevation angle of ~60°. Abundant sonic phenomena were reported including anomalous sounds, explosion booms, sonic booms from individual fragments and whirring sounds interpreted as produced by individual fragments falling to ground; the fireball’s explosions were also widely recorded by Comprehensive Test Ban Treaty infrasound stations establishing an energy release of approximately one third of a kiloton, indicating an original meteoroid mass of ~10 tons. Interviews of eyewitnesses and crude calibrations of security cameras constrained the fall region and the first search attempt led to meteorites being recovered off the ice of a manmade pond late on November 27, 2008. Subsequent searches led to recovery of more than one hundred individual fragments before December 6 when increasing snow cover made further searching unproductive. A strewn field at least seven kilometers long and approximately three km wide with a wind drift tail of an additional three km eastwards has been crudely outlined."

Over 40 kilograms of the Buzzard Coulee meteorite have been recovered to date.

Photo credit: AP Photo/The Canadian Press, Geoff Howe

Peekskill

October's Meteorite of the Month is Peekskill, an ordinary (H6) chondrite that fell October 9, 1992, in New York.

How would you feel if a meteorite wrecked your car?

According to the Meteoritical Bulletin (MB 75), after a fireball and a loud noise the evening of October 9, 1992, a meteorite weighing over 12 kg (~26.5 lb) fell on a car parked in the driveway of a house in Peekskill, New York. The meteorite was found nearly intact under the car – covered in red paint transferred during the impact.

  • This car was hit by the Peekskill meteorite in 1992!

Slice of Peekskill meteoriteChondrites are the most commonly recovered meteorites, accounting for over 85% of all meteorite falls and finds.  They are named for the spherical masses they contain, called chondrules.  The terms chondrule and chondrite are derived from the ancient Greek term chondros, meaning grain.

 

 

 

Benld

Benld is an ordinary (H6) chondrite that fell the morning of September 29th, 1938, in Macoupin County, Illinois.

Benld Meteorite
Photo: The Benld meteorite. Image copyright ASU/CMS/D. Schrader.
The Benld meteorite was only the second meteorite recovered in Illinois (there are now 10 recognized meteorites from the state), and its fall was quite spectacular.

The meteorite was described by B. H. Wilson in Popular Astronomy (1938) as

"crashing out of the battlements of heaven, aimed apparently with the precision of a crack artilleryman, not only striking but penetrating the roof of a garage, as well as the car inside, thereby creating a situation, which, in several respects, is believed to be unique in the annals of meteoric phenomena".

The Benld meteorite was also featured in the Joliet Herald-News (October 1, 1938) under the headline "Should Have Had Meteorite Insurance".

Witnesses to the meteorite's fall did not observe a fireball, and some mistook the sound of the stone's entry for that of a plane's engine.

Car hit by Benld meteorite. Image credit: The Field Museum.

Recovering the Benld meteorite. Image credit: unknown.

 

 

Nanjemoy

Nanjemoy is an ordinary (H6) chondrite that fell at noon on February 10, 1825, in Maryland. It was the first recorded meteorite fall in the state.

Photo copyright ASU/CMS/D. Schrader.

Nanjemoy meteorite

Sioux County

Sioux County is an achondrite (eucrite-mmict) that fell in Nebraska August 8th, 1933. 

The meteorite’s fall to Earth was well-recorded as it was mistaken for an earthquake by some, and written up in local newspapers. Photo copyright CMS/ASU Photo copyright CMS/ASU

This article first appeared on page 5 of the Lincoln Star (Lincoln, Nebraska), Thursday, August 10, 1933:

Report Meteor Buried in Field Near Alliance
ALLIANCE, Neb., Aug. 10 – (AP) The spot where a huge meteor which shook western Nebraska and eastern Wyoming Tuesday landed, was believed located yesterday about 35 northwest of here.
First reports said the meteor buried itself in a field, leaving a hole 25 feet or more across.
The meteor was seen by many persons in western Nebraska as it streaked northward across the sky leaving a long trailing plume of white smoke.
Persons 20 miles north of here saw the meteor apparently explode almost directly west of them with the largest mass of it falling to earth.
To those watchers came a booming roar almost three minutes later. The roar lasted about 30 seconds, a farmer, N.B. Jacobson, who heard it from the field said.
Calls were received here from as far away as Scottsbluff, where the meteor also was seen, asking where the giant explosion was. Telephone lines were busy long after the report as people believed an earthquake or great explosion had occurred. Dishes and windows in homes 15 to 20 miles away were rattled by the concussion.

Eucrites are the most common type of achondrite meteorite falls (vs. finds) and are believed to have formed from the cooling of magma on the surface of the Asteroid 4-Vesta; the number 4 refers to Vesta being the fourth asteroid ever discovered, in March of 1807, by German astronomer Heinrich Wilhelm Olbers.

In September 2007, NASA launched the Dawn mission to study Vesta and the dwarf planet Ceres to provide insight into the formation and evolution of solid bodies in the early solar system, using a visible camera, a visible and infrared mapping spectrometer, and a gamma ray and neutron spectrometer. Dawn stayed in orbit around Vesta for a year, thoroughly studying the asteroid's geology, chemistry and more; insights gained there helped build the link between Vesta and the howardite-eucrite-diogenite (HED) class of meteorites.

 

Johnstown

The Johnstown meteorite fell the afternoon of July 6, 1924, in Weld County, Colorado.

Johnstown is an achondrite (meaning that it formed on a differentiated planetary body, and does not contain chondrules) from the diogenite group.

Part of the HED (Howardites, Eucrites and Diogenites) group of achondrites, diogenites are believed to originate in the crust of Asteroid 4-Vesta. According to radioisotope dating, the HED achondrites crystallized between 4.43 and 4.55 billion years ago. Diogenites are plutonic igneous rocks that form deep in the crust and cool very slowly, resulting in large crystals. They are named for the ancient Greek philosopher Diogenes, who was the first to suggest that meteorites were not terrestrial rocks, and actually originated in space.

Johnstown meteorite

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Photo by L. Garvie © ASU/CMS.

In 2007, NASA launched the Dawn mission to study Vesta and the dwarf planet Ceres, and to provide insight into the formation and evolution of solid bodies in the early Solar System using a visible camera, a visible and infrared mapping spectrometer, and a gamma ray and neutron spectrometer.  The extremely detailed images Dawn captured of Vesta's surface enabled the compilation of high-resolution global geological and tectonic maps of Vesta, published in the journal Icarus by a scientific team led by ASU School of Earth and Space Exploration Associate Research Professor Dr. David Williams.

Read the Meteoritical Bulletin entry for Johnstown, here!