Meteoritical Bulletin: Entry for Cartersville

Writeup from MB 104:

Cartersville 34°12’5.8"N, 84°49’57"W

Georgia, USA

Confirmed fall: March 1, 2009

Classification: Ordinary chondrite (L5)

History: In August 2009, Francis Richards of Cartersville, Georgia, brought a suspected meteorite to the Tellus Science Museum. According to Mrs. Richards she found the meteorite on March 8, 2009, on the floor of an empty rental house she owned. She observed a hole in the bedroom ceiling which aligned with a hole in the roof. Curator then Julian Gray confirmed the identification of the stone as a meteorite. Observations made by Gray and others, and the markings on the stone, determined that the meteorite came through the roof, bounced off a joist, continued through the ceiling of the bedroom and finally bounced off of a painted door before coming to rest on the bedroom floor. Later a neighbor revealed hearing what might have been a sonic boom on March 1, 2009, making this the probable fall date. The meteorite is now in display at Tellus along with other items from the house illustrating its impact.<br><br> (Dr. Marc Fries, NASA ARES) The Cartersville fall event appears in imagery from two NEXRAD radars operated by NOAA. The radars are KHTX (Huntsville, AL), and KFFC (Atlanta, GA). The KFFC radar signature appears at 4.8 km above sea level (ASL) in the 2.5 degree elevation sweep, at 0353 UTC, 02 March 2009. This is 10:53 PM local time. This radar signature appears approximately 9 km laterally from the meteorite find site. It is a prominent image feature that appears in a radar image with very little noise and is separated by more than 70 km from the nearest other radar feature. This is consistent with a radar signature of a meteorite fall that is small in terms of both total mass and total areal extent. The KHTX signature appears in the 1.48 degree sweep at 0350 UTC and 5.4 km ASL, and consists of two proximal radar reflections in the same area as the KFFC signature. The radar data indicate that one of these reflections may be a "range folding" error, and so the KHTX signature alone is not strong stand-alone evidence of a meteorite fall. However, the location of the KHTX feature at the same place and time as the KFFC provides supporting evidence that the object seen on radar is a meteorite fall.

Physical characteristics: The meteorite weighs 295 g and measures 6 cm at its widest dimension. It has a chip that was broken off in flight. Its outer surface is a fused, blackened crust and on its surface are wood fibers from striking the wood joist, gypsum streaks from the ceiling, and paint from the bedroom door.

Petrography: Meteorite is weakly shocked (S3) with minor weathering of grade W1. The ferromagnesian minerals are uniform in size and chondrules and can be readily delineated. The matrix is recrystallized.

Geochemistry: (C. Corrigan, SI) Olivine Fa_23.48±0.17(n=11), Pyroxene Fs_19.31±0.61Wo_0.85±0.79(n=9).

Classification: Ordinary Chondrite (L5)

Specimens: A sample of 20 g and a thin section are on deposit at SI. TSM holds the main mass.

Cartersville: additional information

When Francis Richards brought the meteorite to Tellus Science Museum, curator Julian Gray suspected a meteorite. He consulted with private meteorite collector Dave Gheesling, who visually identified it as an equilibrated L chondrite. This was later classified as L5 by analysis at SI by Catherine Corrigan. A ground hunt in the area near the fall aided by Sean Murray, then president of the Meteorite Association of Georgia, and Robert Ward did not result in any further finds. The sonic boom heard by a neighbor was corroborated by a seismic station in Godfrey, Georgia, USA (GOGA; Latitude 33.4112, Longitude -83.4666) that registered the sound between 0323 and 0324 UTC on 02 March 2009 (10:23 PM and 10:24 PM local time). The previously reported radar images of the fall occurred between 17 and 20 minutes after the detected sonic boom, which would correspond with detection of dust produced by the associated detonation