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Radio Galaxies

PYQs

5

Articles

1

Momentum

15

Phase IFoundation

Background

Overview

Understanding the universe's large-scale structure, galaxy evolution, the role of black holes, and the frontiers of astronomical research. India's contribution to such discoveries highlights its scientific capabilities and advancements in space science.

Radio galaxies are a class of active galaxies that emit powerful radio waves, often far exceeding their optical luminosity. They are typically powered by supermassive black holes at their cores, which accrete matter and launch energetic jets of relativistic plasma into the surrounding intergalactic medium.

Phase IIStatic core

Facts & tables

Key facts

Power Source

Supermassive black holes at their core

Emission

Very high amounts of energy in radio waves

Key Feature

Often launch enormous jets of relativistic magnetised plasma

Interaction

Morphology can reveal interaction with surrounding hot gas and bow shocks

Reference table

Static syllabus anchors

TypeReference
Conceptual areaAstrophysics
Conceptual areaCosmology

Reference table

Institutions & roles

BodyRole
RAD@home Astronomy CollaboratoryDiscovery and research platform
University of MumbaiLead institution for the study
LOFAR (Low Frequency Array)Observational facility used for discovery
Phase IIIExam lens

Prelims angle

Overview

Prelims angle: Multi-statement analysis

Prelims angle: Conceptual understanding

Quick revision

  • Definition: Active galaxies emitting strong radio waves.
  • Power Source: Supermassive black holes at their core.
  • Key Features: Relativistic plasma jets, interaction with intergalactic medium.
  • Significance: Insights into galaxy evolution and cosmic structures.
  • Discovery: RAD-BAARG, a rare 'bow and arrow' type, discovered by Indian team.

High-confidence PYQs

2024Statement-based questions, Conceptual understanding

With reference to radioisotope thermoelectric generators (RTGs), consider the following statements: 1. RTGs are miniature fission reactors. 2. RTGs are used...

Science & TechnologyOpen question
2023Multi-statement analysis, Factual recall

Consider the following statements: 1. Ballistic missiles are jet-propelled at subsonic speeds throughout their flights, while cruise missiles are rocket- pow...

Science & TechnologyOpen question
2022Multi-statement analysis, Conceptual understanding

If a major solar storm (solar-flare) reaches the Earth, which of the following are the possible effects on the Earth? 1. GPS and navigation systems could fai...

Science & TechnologyOpen question
2019Conceptual understanding, Cause and effect relationships

Recently, scientists observed the merger of giant ‘blackholes’ billions of light-years away from the Earth. What is the significance of this observation?

Science & TechnologyOpen question
2018Multi-statement analysis, Factual recall

In which of the following areas can GPS technology be used? 1. Mobile phone operations 2. Banking operations 3. Controlling the power grids Select the c...

Science & TechnologyOpen question

Topic timeline

AstrophysicsCosmology
Prelims 2018· Multi-statement analysis, Factual recall

In which of the following areas can GPS technology be used? 1. Mobile phone operations 2. Banking operations 3. Controlling the power grids Select the c...

Open question
Prelims 2019· Conceptual understanding, Cause and effect relationships

Recently, scientists observed the merger of giant ‘blackholes’ billions of light-years away from the Earth. What is the significance of this observation?

Open question
Prelims 2022· Multi-statement analysis, Conceptual understanding

If a major solar storm (solar-flare) reaches the Earth, which of the following are the possible effects on the Earth? 1. GPS and navigation systems could fai...

Open question
Prelims 2023· Multi-statement analysis, Factual recall

Consider the following statements: 1. Ballistic missiles are jet-propelled at subsonic speeds throughout their flights, while cruise missiles are rocket- pow...

Open question
Prelims 2024· Statement-based questions, Conceptual understanding

With reference to radioisotope thermoelectric generators (RTGs), consider the following statements: 1. RTGs are miniature fission reactors. 2. RTGs are used...

Open question

Indian team discovers rare ‘bow and arrow’ radio galaxy two billion light years from Earth

03 Jul 2026 · Radio galaxies are active galaxies driven by central supermassive black holes, characterized by strong radio emissions and often large-scale jets. Their study provides insights into cosmic evolution and intergalactic processes, with recent discoveries like RAD-BAARG by Indian researchers advancing our understanding.

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Related topics

Current topic

Radio Galaxies

Often confused with

Radio Astronomy & Telescopes

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Practice writing on this topic

UPSC has asked 5 linked questions on Radio Galaxies in Mains. Write an answer to one — and get it evaluated.

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