Decoding a meteorite

#GS3 #SCIENCE

On June 6, 2017, residents of Mukundpura village near Jaipur saw a bright trail in the sky followed by a thunderous sound. They spotted a burning object with a sulphur smell on the soft agricultural land.

 

  • The meteorite broke into several fragments, but a pit of about 15 cm in diameter and 10 cm in depth was formed at the impact site. 

 

Carbonaceous chondrite

  • The meteorite named Mukundpura CM2 was classified to be a carbonaceous chondrite
  • This is a type of stony meteorite, considered the most primitive meteorite and a remnant of the first solid bodies to accrete in the solar system
  • The composition of carbonaceous chondrites are also similar to the Sun.
  • Meteorites are broadly classified into three groupsstony (silicate-rich), iron (Fe–Ni alloy), and stony-iron (mixed silicate–iron alloy).
  • Chondrites are silicate-droplet-bearing meteorites, and this Mukundpura chondrite is the fifth carbonaceous meteorite known to fall in India.

 

Degrees of alteration

  • The study revealed that Mukundpura CM2 had experienced varying degrees of alteration during the impact. 
  • Some minerals like forsterite and FeO olivine, calcium aluminium rich inclusion (CAI) minerals escaped alteration
  • Few magnetites, sulphides and calcites were also found. 
  • Detailed spectroscopic studies revealed that the meteorite had very high (about 90%) phyllosilicate minerals comprising both magnesium and iron
  • Further X-ray studies showed it also had aluminium complexes.

 

Relevance to asteroids

  • The Mukundpura CM2 study are relevant to the surface composition of near-Earth asteroids Ryugu and Bennu
  • In October 2020, NASA’s OSIRIS-REx mission collected samples from Bennu and is expected to return in September 2023. 
  • Last month, Japan’s Hayabusa-2 mission landed on Earth with samples from Ryugu.
  • Infrared spectroscopy results suggest that spectral properties of the surface of these asteroids are consistent with CM carbonaceous meteorites. 
  • Therefore, a better understanding of the nature and evolution of such meteorites that have been aqueously altered will help considerably in the interpretation of results of these missions.

 

Early solar system

  • Meteorites are representative of asteroids. Asteroids are the remnant debris of the inner solar system formation process and thus offer the formation history or the building blocks of the planets. 
  • Therefore, by studying meteorites in the laboratory and asteroids by exploration and sample return mission we try to reconstruct the activity of early solar system events
  • Also, asteroids are often rich in volatiles and other minerals and can be exploited for future planetary exploration.
Print Friendly and PDF
blog comments powered by Disqus