Meteorite (Ulka Pind): Types, Famous Falls in India & Science

A meteorite — ulka pind (उल्का पिंड), the Hindi and Sanskrit term for it — is a solid fragment of extraterrestrial rock or metal that survives passage through Earth's atmosphere and lands on the surface. Meteorites are among the oldest known materials in the Solar System — many are ~4.56 billion years old, formed at the same time as the Sun and planets — and they carry direct evidence of the Solar System's birth, the composition of asteroids, and even the origin of organic molecules that may have seeded life on Earth.

For UPSC aspirants, meteorites are a recurring GS3 (Science & Technology) and GS1 (Geography) topic — covering planetary science, impact craters, and the Physical Research Laboratory (PRL), Ahmedabad, which curates India's national meteorite collection.

Meteoroid, Meteor, Meteorite — Key Distinctions

Origin of Meteorites

Most meteorites originate from:

• The Asteroid Belt — between Mars and Jupiter; contains millions of asteroids (Ceres, Vesta, Pallas are the largest)
• Near-Earth Objects (NEOs) — asteroids whose orbits cross or approach Earth
• The Moon — lunar meteorites ejected by lunar impacts
• Mars — Martian meteorites (about 300 confirmed worldwide)
• Comets — rare, produce mostly meteor showers rather than meteorites

Types of Meteorites

1. Stony Meteorites (~94% of falls)

Composed mainly of silicate minerals.

a. Chondrites (~86%)

• Contain chondrules — small round silicate droplets formed in the early Solar System
• Have never been melted or differentiated
• Considered the most primitive material — direct samples of the solar nebula
• Sub-types: Ordinary chondrites (H, L, LL), Enstatite chondrites, Carbonaceous chondrites

b. Achondrites (~8%)

• Lack chondrules — come from differentiated parent bodies (e.g., Moon, Mars, Vesta)
• Resemble igneous rocks
• Include lunar and Martian meteorites

2. Iron Meteorites (~5%)

• Composed of iron-nickel alloys (kamacite and taenite)
• Originate from the cores of differentiated asteroids
• Display the characteristic Widmanstätten pattern when polished and etched
• Extremely dense

3. Stony-Iron Meteorites (~1%)

• Mixture of silicate and iron-nickel
• Sub-types: Pallasites (olivine crystals in iron matrix — prized by collectors), Mesosiderites

Carbonaceous Chondrites and the Origin of Life

Carbonaceous chondrites (CI, CM, CO, CV) are the most scientifically significant class:

• Contain water (hydrated minerals) — up to 20%
• Contain organic molecules including amino acids — the building blocks of proteins
• Murchison meteorite (1969, Australia) — 96 amino acids identified
• Ryugu samples (Japan's Hayabusa2, 2020) and Bennu samples (NASA's OSIRIS-REx, 2023) — both revealed organic compounds and hydrated minerals
• Support the hypothesis that meteorites and comets delivered water and organics to early Earth — the panspermia / exogenous delivery model

Famous Meteorite Falls and Impact Sites in India

Lonar Crater — Deeper Look

• Age: ~52,000 years (Pleistocene)
• Formed by: hypervelocity impact of a stony meteorite on Deccan basalt
• Size: 1.83 km diameter; 150 m deep
• Status: Geo-heritage site (GSI); Ramsar site (November 2020) — lake is both saline and alkaline
• Scientific importance: analogue for Martian impact craters on basalt (studied by NASA and ISRO)
• Near-circular lake inside the crater; unique ecosystem

Kumbakonam (Sulagiri) Meteorite — 2008

• Fall: September 12, 2008
• Village: Sulagiri, Krishnagiri district, Tamil Nadu
• Type: L6 ordinary chondrite
• Total mass recovered: ~140 kg — largest Indian meteorite fall of the 21st century
• Pre-atmospheric mass estimated ~1 tonne

Organisations Working on Meteorites in India

Physical Research Laboratory (PRL), Ahmedabad

• India's nodal agency for meteorite curation and research
• Maintains the national meteorite repository
• Conducts isotopic, geochemical, and petrological analyses
• Part of the Department of Space
• Founded: 1947 by Dr. Vikram Sarabhai

Other Institutions

• Geological Survey of India (GSI) — impact crater mapping
• ISRO — planetary science via Chandrayaan, Mars Orbiter
• IITs and IISc — cosmochemistry research
• Indian Institute of Astrophysics (IIA), Bengaluru
• Indian Institute of Space Science & Technology (IIST), Thiruvananthapuram

Meteorite vs Asteroid vs Comet

Global Major Impact Events

Planetary Defence

• NASA's DART Mission (September 2022) — successfully altered orbit of asteroid Dimorphos — first planetary-defence test
• ESA's Hera (2024 launch) — follow-up study of Dimorphos
• ISRO's planetary-defence studies — tracking NEOs
• UN Space Mission Planning Advisory Group (SMPAG) coordinates global response

UPSC Relevance

GS3 (Science & Technology): Planetary science, cosmochemistry, space missions, sample-return missions (Hayabusa2, OSIRIS-REx).

GS1 (Geography): Impact craters, Lonar lake, geo-heritage sites.

GS3 (Environment): Ramsar site — Lonar Lake (2020).

Key Prelims facts:

• Meteoroid → Meteor → Meteorite (progression)
• Meteoroid in space; meteor in atmosphere; meteorite on ground
• Oldest meteorites: ~4.56 billion years
• Three main types: Stony (~94%), Iron (~5%), Stony-Iron (~1%)
• Chondrites have chondrules; achondrites do not
• Carbonaceous chondrites contain amino acids and water
• Lonar Lake — Maharashtra; basaltic impact crater; Ramsar site (2020)
• Ramgarh Crater — Rajasthan
• Dhala Crater — Madhya Pradesh (oldest in India)
• Kumbakonam (Sulagiri) meteorite — Tamil Nadu, 2008, L6 chondrite, ~140 kg
• Dhajala — Gujarat, 1976
• Piplia Kalan — eucrite from asteroid Vesta
• PRL Ahmedabad — custodian of India's meteorite collection
• PRL founded by Vikram Sarabhai (1947)
• DART mission (NASA) — 2022 — hit asteroid Dimorphos
• Chicxulub crater — dinosaur extinction (~66 mya)
• Tunguska event: 1908; Chelyabinsk: 2013
• Widmanstätten pattern — in iron meteorites