Lead IAS Daily Bulletin - 18 December - Smog, IRDAI, Dark Matter, Helicopters in News

Sep 20, 2026

Uploaded by Ezra

18 December 2025 daily bulletin covering four current knowledge themes. It explains smog formation, components, key types (sulphurous and photochemical), health and visibility impacts, and contrasts haze vs smog, including temperature inversion and the Gothenburg Protocol (1999). It also summarizes IRDAI and the Lok Sabha passage of the Sabka Bima Sabki Raksha Bill, 2025, plus PFRDA’s role. Finally, it discusses a possible dark matter gamma-ray signal and compares dark matter with dark energy, followed by Indian Navy and air force helicopter updates.

LanguageEnglish

CategoryResearch & Report

FormatPDF

Pages5

Reading Time13 min

AccessFree to download

Smog

Types, effects, and haze vs smog

Temperature inversion and Gothenburg Protocol (1999)

IRDAI and insurance reforms

Sabka Bima Sabki Raksha Bill, 2025

IRDAI and regulated entities

PFRDA overview

Dark matter and dark energy

Possible signal and composition

Dark matter vs dark energy comparison

Helicopters in news

Indian Navy MH-60R squadron and related platforms

18 December 2025 Smog Delhi is facing dense smog, causing low visibility and disrupting flight operations. o Smog is formed when smoke mixes with fog or sunlight. It reduces visibility and harms health. o Smog = Smoke + Fog. o Components: Includes soot particulates, sulphur dioxide (SO₂), nitrogen dioxide (NO₂), hydrocarbons, carbon monoxide (CO), and ozone (O₃) . o Types of Smog: o Sulphurous Smog (London Smog): First observed in London, sulphurous smog is caused by sulphur oxides released from burning sulphur-rich coal. It is aggravated by high humidity, high suspended particulate matter, and is common in cold, humid climates. o Photochemical Smog (Los Angeles Smog / Summer Smog): Occurs mainly in urban areas with heavy automobile traffic, where nitrogen oxides (NOx) and hydrocarbons are the primary pollutants. Forms in the presence of sunlight and produces ozone (O₃) as a secondary pollutant. o Effects: Respiratory distress, eye irritation, plant damage, reduced visibility, carcinogenic risk, worsened by inversion layers and low rainfall. o Haze vs. Smog: Haze = dry particles reducing visibility; Smog = pollutants with condensation. o Temperature inversion is a condition in which warm air traps cooler air near the ground, preventing pollutant dispersion and increasing air pollution. o Gothenburg Protocol (1999): It aims to reduce key smog-forming pollutants such as sulphur dioxide (SO₂), nitrogen oxides (NOx), ammonia (NH₃), and volatile organic compounds (VOCs), especially those causing photochemical smog. IRDAI The Lok Sabha passed the Sabka Bima Sabki Raksha (Amendment of Insurance Laws) Bill, 2025 to reform India’s insurance framework by amending the Insurance Act, LIC Act, and strengthening IRDAI. o Insurance Regulatory and Development Authority of India is a statutory, quasi-Judicial and autonomous body. o It protects policyholders’ interests and regulates, promotes, and ensures the orderly growth of the insurance industry in India. o Established: in 1999, by the Insurance Regulatory and Development Authority of India Act, 1999. o Ministry: operates under the Department of Financial Services in the Ministry of Finance. o Headquarters: Hyderabad, Telangana. o Composition: Chairperson + not more than 9 members-all appointed by the Government of India. o Entities regulated: Life Insurance companies and General Insurance companies (covering health, motor, fire etc) . Reinsurance companies and insurance Intermediaries (Brokers, corporate agents, web aggregators, third party administrators etc) . o PFRDA (Pension Fund Regulatory and Development Authority): is a Statutory body under Ministry of Finance. It regulates and develops India’s pension sector, including NPS and Atal Pension Yojana. Dark Matter Scientists have reported a possible dark matter signal from gamma rays in the Milky Way, but experts caution that it needs further verification. o Dark matter is an invisible form of matter that does notemit, absorb, or reflect light, and is detected only through its gravitational effects. o The universe is composed of about 5% ordinary (baryonic) matter, 27% dark matter, and 68% dark energy. o Discovery: Fritz Zwicky proposed dark matter in the 1930s after observing that galaxies in the Coma Cluster were moving too fast to be held together by visible matter alone. o Nature of Dark Matter: o Dark: Dark matter does not interact with electromagnetic radiation, so it does not emit, absorb, or reflect light and is not present as stars or planets. o Not antimatter: If it were antimatter, gamma rays from matter–antimatter annihilation would be detected. o Possible composition – Weakly Interacting Massive Particles (WIMPs): WIMPs are massive subatomic particles that interact very weakly with ordinary matter. o WIMP candidates: Axions- Neutralinos, and Neutrinos o Since about 27% of the universe consists of dark matter, the WIMP hypothesis is strongly favoured, though d

FAQs

What causes smog and what pollutants are included in it?

Smog forms when smoke mixes with fog or sunlight and reduces visibility while harming health. It includes soot particulates, sulphur dioxide (SO₂), nitrogen dioxide (NO₂), hydrocarbons, carbon monoxide (CO), and ozone (O₃).

How do sulphurous smog and photochemical smog differ?

Sulphurous smog (London Smog) is linked to sulphur oxides from burning sulphur-rich coal and is worsened by high humidity and suspended particulates. Photochemical smog (Los Angeles/Summer Smog) occurs in urban areas with heavy vehicle traffic, driven by NOx and hydrocarbons in sunlight, producing ozone as a secondary pollutant.

What is the key difference between dark matter and dark energy based on their effects and abundance?

Dark matter is hypothesised non-baryonic matter forming about 27% of the universe and exerts an attractive gravitational binding force, influencing galaxy and cluster dynamics. Dark energy is a hypothetical energy form making up about 68% of the universe and is associated with cosmic acceleration and the universe’s large-scale expansion.

Sep 20, 2026

Uploaded by Ezra