Physical Research Laboratory (PRL), Ahmedabad’s scientists recently identified a meteorite that crashed in two Banaskantha villages, Gujarat, on August 17, 2022. This meteorite is an aubrite, a rare type of meteorite, as confirmed by gamma-ray spectrometer analysis of its mineral composition. Alongside this, the meteorite has been classified as a monomict breccia.
Aubrite Meteorites: Their Composition and Occurrences
An Aubrite meteorite is a coarse-grained igneous rock. Notably, these rocks form under oxygen-poor conditions, housing unusual minerals not seen on Earth. For instance, the mineral heideite was initially identified in a Basti meteorite. Although India has witnessed many meteorite crashes, this incident marks only the second recorded aubrite crash.
This particular meteorite has been christened the Diyodar meteorite, named after the taluka where the crash happened. The last known crash of an aubrite, before Diyodar, took place in Basti, Uttar Pradesh, on December 2, 1852.
A significant 90% of this meteorite comprises orthopyroxene, a type of pyroxene. Pyroxenes are silicates featuring single silica tetrahedra chains (SiO4), with orthopyroxenes having a specific structure. Many pyroxenes, like diopside and jadeite, have gem applications, while spodumene has historically served as lithium ore. Meanwhile, construction practices utilize crushed stones made from pyroxene rocks.
Since 1836, at least 12 locations globally have experienced aubrite crashes, with 3 based in Africa and 6 in the US.
Understanding Meteorites and Their Types
A meteorite constitutes a solid piece of debris from space that withstands its journey through the Earth’s atmosphere to land on the Earth’s surface. However, distinctions exist between meteors, meteorites, and meteoroids, all of which relate to their location.
Meteoroids are objects in space. Their sizes vary from dust grains to small asteroids. When these meteoroids enter Earth’s atmosphere, they are termed meteors. If the meteoroid enters the Earth’s atmosphere and reaches the ground, it is referred to as a meteorite.
What is a Gamma Ray Spectrometer?
Gamma-ray spectrometers are scientific instruments that measure the energy distribution of gamma rays emitted by radioactive substances. These devices have three main components: a detector, electronics, and software for analyzing data.
The resultant gamma-ray spectrum can identify present radioactive isotopes and their relative abundance. Gamma-ray spectrometers play vital roles across various fields like environmental monitoring, geology, and nuclear physics. They can detect and measure radiation from natural sources such as rocks and soils, and human-made sources like nuclear power plants and medical facilities.