On June 6, 2017, Mukundpura village near Jaipur witnessed a bright trail in the sky, followed by a thunderous sound. Later, a burning object with a sulphurous smell was found on the soft agricultural land, broken into several fragments. It caused a pit of about 15 cm in diameter and 10 cm in depth at the impact site. It was handed over to the Geological Survey of India, Kolkata to study the mineralogy of the meteorite. The study revealed that the fragments were parts of the fifth meteorite known to have fallen in India. The other four are Piplia Kalan, Sulagiri, Shergotty, and Bishunpur.
The meteorite was named Mukundpura CM2, and was classified to be a carbonaceous chondrite, which is a type of stony meteorite. It is considered to be the most primitive meteorite and a remnant of the first solid bodies which accreted in the solar system. According to Dwijesh Ray from the Physical Research Laboratory, Ahmedabad, the composition of carbonaceous chondrite is similar to that of the Sun.
The meteorite had experienced varying degrees of alteration during the impact. Some minerals such as forsterite and FeO olivine, calcium aluminium rich inclusion (CAI) minerals did not alter. Some other minerals like few magnetites, sulphides, and calcites were also found. It had about 90 per cent phyllosilicate minerals consisting of magnesium and iron. Aluminium complexes were also found.
The results of the Mukundpura CM2 study are relevant to the surface composition of near-Earth asteroids, namely, Ryugu and Bennu, from where samples were collected in October 2020 by NASA’s OSIRIS-REx mission, which is expected to return in September 2023. Japan’s Hayabusa-2 mission landed on Earth with samples from Ryugu in December 2020.
Spectral properties of the surface of these asteroids are also consistent with CM carbonaceous meteorites. So, a better understanding of the nature and evolution of such meteorites will help interpret the results of the above-mentioned missions to a great extent.
Importance of Meteorites
Meteorites represent asteroids, which are the remnant debris of the inner solar system formation process. They offer the opportunity to study the formation history or the building blocks of the planets. As such, their study in the laboratory helps in reconstructing the activity of early solar system events. Asteroids are also often rich in volatiles and other minerals and can be studied for future planetary exploration.