Meteorites, probably the debris of celestial bodies torn apart by collision or near approach range from solid bodies of nickel-iron to rocks similar to those found on the earth. Meteorites large enough to disfigure the earth's surface appreciably when they hit have been rare, but the Meteor Crater at Odessa is at least 500 feet in diameter. The gentle topography, character of the soil, and size of the state have a bearing on the number of meteorites found in Texas, but an important factor also is the interest of scientists at the University of Texas and of such private individuals as Oscar Monnig of Fort Worth, who recovered many old falls and investigated every reported fireball during much of the twentieth century. A number of noteworthy meteorites have been discovered in Texas. Probably the earliest written reference to meteoritic iron was made by Athanase de Mézières in 1772. While on an expedition near the Brazos River he visited an Indian village and learned of the Texas Iron from Indians who venerated the meteorite and attributed extraordinary powers to it. In 1808 Indian trader Anthony Glass saw it; the iron was taken down the Red River to Natchitoches, Louisiana, in 1810. After being on exhibition in several cities it was permanently stored at Yale University in 1835.
Records of meteorite discoveries have helped to chronicle the number of collected specimens in the state throughout the years. A catalog of 1940 listed Texas as having had seventy meteorites, and a catalog of meteorites of the world published in 1946 listed Texas as having had seventy-nine falls. The Peña Blanca Spring meteorite, which plunged into a swimming pool on the Gage ranch in Brewster County on August 2, 1946, was not listed in either publication. With eighty meteorites by 1947, Texas had thirty more than any other state and accounted for 6 percent of the known meteorites in the world. The number of recognized meteorite localities in Texas increased to 104 by 1962, and additional reports up to 1966 raised the number to 128. Some authorities were studying meteorite localities in close proximity with the idea that they could be related, and the count of localities would thus be somewhat reduced. At that time, of the named meteorites, thirty-four were irons; one was a pallasite (part iron, part olivine); and ninety-three were of various stony types, mostly chondrites. Stony meteorites always greatly outnumber all others. At least seventeen of the localities were sites of multiple pieces, especially as the stones often fall in groups. The Plainview, Dimmitt, and Tulia showers in the Panhandle have yielded hundreds of specimens due to extensive collecting efforts in favorable, almost rock-free country, and a cooperative population.
There have been two iron showers in the state; one of these resulted in the formation of the Meteor Crater at Odessa. The Odessa crater has been further explored by Glen Evans. Ninety-three drill holes demonstrated the absence of meteoritic material beneath the crater and confirmed the theory that a sufficiently large impacting meteorite does not bury itself, but is ejected from the crater by explosion and falls in fragments on the surrounding area. However, it was shown at Odessa that there was a buried, adjoining, seventy-foot-diameter crater containing a concentrated cluster of badly oxidized meteoritic nickel-iron. This smaller crater was clearly of the impact type and did not explode; there are probably one or more similar smaller impact sites nearby. The Odessa Meteoritical Society erected a small museum on the northeast rim and upgraded and safeguarded the crater area, which received a Texas State Historical Survey Committee marker in 1962 and was designated a Registered Natural Landmark in 1965 by the National Park Service.
The Sierra Madera structure, marked by an irregular set of hills just east of a highway twenty miles south of Fort Stockton, is considered by some authorities to be the site of a possible huge meteorite impact. That considerable geologic disturbances occurred there is a well-established fact. Some authorities argue that the absence of derangement with depth and the presence of shatter cones in the dolomite of the central area denote an impact from above. According to this theory, all meteorite fragments and the accompanying crater itself were eroded away long ago, leaving only an anticlinal reaction exposed. Other authorities dispute this interpretation, and the structure is still under detailed investigation.
Texas has had at least nine cases of "falls"-meteorites recovered from a witnessed fireball. All were of some stony type. By an unusual coincidence, two falls occurred in Northeast Texas in 1961 within approximately 100 miles of each other and within a period of only a little over 100 days. The Harleton, Texas, eighteen-pound chondrite fell in a man's backyard near Marshall shortly before 10:30 P.M. on May 30, 1961, and was recovered within thirty minutes from a reported depth of about two feet in soft sand. It was distributed among scientists for a careful study of a freshly fallen meteorite, especially with respect to cosmic-ray-induced effects. On September 9, 1961, at 10:08 P.M., a detonating fireball was witnessed passing northward just east of the Fort Worth-Dallas region. It terminated near Bells, Grayson County. Some ten ounces of a very rare carbonaceous chondrite was retrieved from the meteorite over a six-month period. Only about twenty ounces of this substance had been known previously to fall in the world. This type of meteorite is quite fragile. Only one piece was recovered in a fresh condition; all the others became wet from the torrential rains of Hurricane Carla of that year. On September 20, 1980, witnesses saw a bright fireball in San Saba County. A subsequent search was organized, and fragments were found near Richland Springs.
By the end of 1992 a total of approximately 231 meteorites had been cataloged in Texas. Collections and displays of meteorites include those at the Texas Memorial Museum at the University of Texas at Austin, the W. L. Moody Visitor's Center at the University of Texas at Austin McDonald Observatory near Fort Davis, and the geology department at Texas Christian University in Fort Worth, which has the extensive meteorite collection of Oscar Monnig.