Study Notes

Everything published under Study Notes on Anantam IAS, newest first.

3454 articles

Artist illustration of NASA's Chandra X-ray Observatory in orbit, named after Subrahmanyan Chandrasekhar.

5 Oct 2026General Studies, GS III, Science & Tech

Subrahmanyan Chandrasekhar: Chandrasekhar Limit, 1983 Nobel and Chandra

Subrahmanyan Chandrasekhar explained: the white dwarf mass limit, his clash with Eddington, the 1983 Nobel Prize and why NASA named Chandra after him.

An AK-203 assault rifle of the Indian Army.

5 Oct 2026General Studies, GS III, Internal Security, Science & Tech

AK-203 Rifle: Korwa Joint Venture, INSAS Replacement and Indigenisation

AK-203 explained: the Indo-Russian joint venture at Korwa, the 2021 contract for 6,01,427 rifles, why INSAS is being replaced and how indigenisation is going.

Portrait photograph of environmental engineer G. D. Agrawal, later known as Swami Sanand, taken in 2011.

5 Oct 2026Environment & Ecology, General Studies, GS III

G.D. Agarwal (Swami Sanand): IIT Professor, CPCB Pioneer and the Ganga Fasts

GD Agarwal explained: Berkeley-trained engineer, first CPCB member secretary, Swami Sanand, the Bhagirathi fasts and his 111-day fast for a Ganga law.

Satellite view of a broad band of cloud from a western disturbance stretching across Afghanistan, Pakistan and northern India on 3 February 2013.

5 Oct 2026General Studies, Geography, GS I, Physical Geography

Western Disturbance: Jet-Stream Storms, Winter Rain and the Rabi Crop

Western disturbance explained: subtropical westerly jet, Mediterranean origin, winter rain and snow, rabi crops, cold waves, hail and the monsoon clash of 2013.

Humayun's Tomb in Delhi veiled in dense fog on a winter morning.

5 Oct 2026Disaster Management, General Studies, Geography, GS I

Cold Wave in India: IMD Criteria, Cold Day vs Cold Wave and NDMA Guidelines

Cold wave explained: IMD departure and absolute criteria, cold day vs cold wave, the core cold wave zone, health and crop impact and NDMA's…

A hand holding several white hailstones above a strawberry patch strewn with hail after a storm.

5 Oct 2026Disaster Management, General Studies, Geography, GS I, Physical Geography

Hailstorm: How Hail Forms, Where India Gets It and How Crop Loss Is Insured

Hailstorm explained: cumulonimbus updrafts, the 5 to 50 mm hailstone, India's February to May hail belt, IMD warnings and PMFBY cover.