Characterizing a New Meteorite Fall from Mahadeva, India

Panda, Ray, and Shukla, 2020

Eyewitnessed meteorite falls always evoke excitement in the planetary science community because, if immediately collected, fresh falls are relatively uncontaminated by the terrestrial environment. On July 22, 2019, a meteor was seen falling on the Mahadeva village in the Madhubani district in the state of Bihar in India. Witnesses saw the meteorite impact in broad daylight, where it was found in a paddy field having created a 1.5-meter-deep hole. The meteorite weighed approximately 15 kilograms and is currently housed in the Patna Science Museum. However, a small portion of the meteorite was sent to the Physical Research Laboratory in Ahmedabad, India where it was chemically and texturally characterized by Dipak Panda and colleagues.

The meteorite resembles an ordinary chondrite because it contains relict chondrules, small spherical, melt-textured objects that formed in the early solar nebula. The chondrules range in size from a few hundred microns to more than two millimeters across and are made up of several different minerals that contain components such as iron (Fe) and silica (SiO2). In addition to chondrules, the meteorite contains grains of metal and metal alloys. Panda and colleagues were able to use the compositions of several minerals to infer that the meteorite experienced temperatures of approximately 800°C. These temperatures categorize the meteorite as petrographic type 5/6, meaning that it experienced significant thermal metamorphism (type 3 is unheated, while types 4 through 6 have been progressively heated). Furthermore, this meteorite can be classified as an H chondrite (high-iron ordinary chondrite) based on its mineralogy and mineral compositions. Freshly fallen chondrites are particularly valuable to the planetary science community because they typically contain very old (~4.55 billion years old) material from the early solar nebula that has not been altered by terrestrial weathering. Thus, they can provide scientists with a wealth of new data that yield insights into early solar system processes. READ MORE