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GS Paper: GS3-16.Achievements of Indians in Science & Technology

  • Visible Emission Line Coronagraph (VELC) onboard Aditya-L1

    Why in the News?

    Scientists at the Indian Institute of Astrophysics (IIA), in collaboration with NASA, have made the first spectroscopic observations of a Coronal Mass Ejection (CME) in the visible wavelength range, using the Visible Emission Line Coronagraph (VELC) aboard Aditya-L1.

    About Visible Emission Line Coronagraph (VELC):

    • Overview: The VELC is the primary scientific payload onboard Aditya-L1, India’s first solar observatory mission.
    • Developer: Designed and built by the Indian Institute of Astrophysics (IIA) at its CREST campus, Hosakote (Karnataka).
    • Function: It is an internally occulted coronagraph capable of imaging, spectroscopy, and spectro-polarimetry of the solar corona, the outermost layer of the Sun’s atmosphere.
    • Objective: To study coronal mass ejections (CMEs), solar wind acceleration, coronal temperature, plasma velocity, and magnetic field dynamics close to the solar limb.
    • Capabilities:
      • Observes the corona as close as 1.05 solar radii from the Sun’s surface.
      • Equipped with a spectrograph, polarimeter, and detectors for high-resolution data.
      • Enables continuous 24-hour solar observation from Lagrange Point L1.
    • Significance: Provides first-ever spectroscopic data of CMEs near the Sun, enhancing understanding of space weather and solar activity.
    • Key Findings:
      • Electron Density: ~370 million electrons per cubic centimetre within the CME, several times higher than the ambient solar corona (10–100 million/cm³).
      • Energy: ~9.4 × 10²¹ joules- nearly 100 trillion times the energy released by the Hiroshima bomb.
      • Mass: ~270 million tonnes- about 180 times the mass of the iceberg that sank the Titanic.

    Back2Basics: Aditya-L1 Mission

    • Overview: India’s first space-based solar mission, developed by the Indian Space Research Organisation (ISRO).
    • Launch & Position: Launched in 2023; placed at the Lagrange Point 1 (L1), approximately 1.5 million km from Earth, providing an uninterrupted view of the Sun.
    • Purpose: To study the Sun’s outer atmosphere (corona), solar radiation, magnetic storms, and space weather phenomena.
    • Key Objectives:
      • Understand the dynamics of solar corona and solar wind.
      • Study solar flares, CMEs, and their impact on Earth’s magnetosphere.
      • Monitor space weather to protect satellites and communication systems.
    • Scientific Payloads (7 instruments):
      1. VELC – Visible Emission Line Coronagraph (solar corona imaging).
      2. SUIT – Solar Ultraviolet Imaging Telescope.
      3. SoLEXS – Solar Low Energy X-ray Spectrometer.
      4. HEL1OS – High Energy L1 Orbiting X-ray Spectrometer.
      5. ASPEX – Aditya Solar Wind Particle Experiment.
      6. PAPA – Plasma Analyser Package for Aditya.
      7. Magnetometer – Measures magnetic fields at L1.
    • Significance:
      1. First Indian mission to continuously observe the Sun.
      2. Strengthens India’s position in global heliophysics research.
      3. Provides early warnings for geomagnetic storms affecting satellites and power grids.
    [UPSC 2022] 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 fail.

    2. Tsunamis could occur at equatorial regions.

    3. Power grids could be damaged.

    4. Intense auroras could occur over much of the Earth.

    5. Forest fires could take place over much of the planet.

    6. Orbits of the satellites could be disturbed.

    Select the correct answer using the code given below:

    (a) 1 and 2 only (b) 3 and 4 only (c) 1, 3, 4 and 6 only* (d) 2, 5 and 6 only

     

  • [pib] Indian Navy commissions INS Ikshak

    Why in the News?

    The Indian Navy has commissioned INS Ikshak, the third Survey Vessel (Large) (SVL) and the first to be based at the Southern Naval Command, at Naval Base Kochi.

    About INS Ikshak:

    • Overview: It is the third vessel of the Survey Vessel (Large) [SVL] class and the first to be based at the Southern Naval Command.
    • Series Lineage: Third ship in the SVL series, following INS Sandhayak and INS Nirdeshak, replacing older Sandhayak-class vessels.
    • Builder & Origin: Constructed by Garden Reach Shipbuilders & Engineers (GRSE) Ltd., Kolkata, under Aatmanirbhar Bharat, with over 80% indigenous content sourced from Indian MSMEs.
    • Name Meaning: Means ‘Guide’ in Sanskrit – symbolising its role in charting unexplored waters and strengthening maritime safety in the Indian Ocean Region (IOR).
    • Mission Role: Designed primarily for hydrographic surveys but also configured for Humanitarian Assistance and Disaster Relief (HADR) operations and can serve as a hospital ship during crises.

    Key Features:

    • Dimensions & Displacement: 110 m long, 16 m wide, 3,400-ton displacement, with crew capacity of ~231 personnel.
    • Propulsion & Speed: Powered by twin main engines and twin-shaft configuration; achieves 14 knots cruising speed, 18 knots maximum.
    • Survey Systems: Equipped with multi-beam echo sounder, Autonomous Underwater Vehicle (AUV), Remotely Operated Vehicle (ROV), four Survey Motor Boats (SMBs), and advanced oceanographic sensors for coastal and deep-water mapping.
    • Aviation Facility: Features a helicopter deck, extending its range, reconnaissance, and operational versatility.
    • Dual Role Capability: Convertible for HADR and medical missions, enhancing naval disaster-response capability.
    • Gender-Inclusive Design: India’s first survey vessel with dedicated accommodation for women officers and sailors.
    [UPSC 2016] Which one of the following is the best description of ‘INS Astradharini’, that was in the news recently?
    Options: (a) Amphibious warfare ship
    (b) Nuclear-powered submarine
    (c) Torpedo launch and recovery vessel *
    (d) Nuclear-powered aircraft carrier

     

  • ISRO’s LVM3 Rocket launches GSAT-7R

    Why in the News?

    The Indian Space Research Organisation (ISRO) has successfully launched the GSAT-7R (CMS-03) communication satellite for the Indian Navy from the Satish Dhawan Space Centre, Sriharikota.

    Back2Basics: Launch Vehicle Mark-3 (LVM3) Rocket  

    • Overview: LVM3 formerly GSLV Mk-III, is ISRO’s heaviest and most powerful launch vehicle, built to lift 4-tonne GTO and 8-tonne LEO payloads.
    • Configuration: A 3-stage system – (1) S200 solid boosters, (2) L110 liquid core (UH25 + NO), and (2) C25 cryogenic upper stage (LH + LOX) providing high thrust and precision.
    • Payload Capacity: Delivers ~4,000 kg to GTO and ~8,000 kg to LEO; GSAT-7R demonstrated >4,400 kg capability, setting a new record.
    • Mission Legacy: Successfully launched Chandrayaan-2, Chandrayaan-3, OneWeb satellites, and Gaganyaan crew module tests.
    • Cryogenic Stage: The C25 engine produces ~20 tonnes thrust; the upgraded C32 stage (22 tonnes thrust) is under development.
    • Future Upgrade: Plans to replace L110 with a semi-cryogenic kerosene–liquid oxygen stage for higher efficiency and lower cost.
    • Reliability & Role: With seven consecutive successes, LVM3 is India’s most dependable heavy launcher and baseline vehicle for Gaganyaan and Bharatiya Antariksh Station missions.
    • Strategic Significance: Establishes India’s complete autonomy in heavy launch capability, strengthening its position in the global space economy.

    About GSAT-7R (CMS-03):

    • Overview: An advanced multiband communication satellite developed to strengthen the Indian Navy’s secure communications and maritime domain awareness across the Indian Ocean Region (IOR).
    • Developer & Design: Indigenously designed by ISRO under Aatmanirbhar Bharat, advancing self-reliance in defence space infrastructure.
    • Mass & Orbit: Weighs ~4,410 kg, the heaviest communication satellite launched from Indian soil; inserted into Geosynchronous Transfer Orbit (GTO) before shifting to Geostationary Orbit (~36,000 km).
    • Technical Features: Equipped with secure, high-throughput multiband transponders supporting voice, data, and video links across ships, submarines, and aircraft.
    • Coverage & Capability: Provides pan-Indian Ocean coverage, enabling real-time encrypted communication and Blue Water operational readiness.
    • Strategic Role: Functions as a key node in the Defence Communication Network (DCN), enhancing situational awareness and naval coordination.
    • Predecessor: Succeeds GSAT-7 (Rukmini, 2013) with expanded range, bandwidth, and capacity.
    • Significance: Symbolises India’s move toward indigenous defence satellites, merging space technology and national security.
    [UPSC 2018] With reference to India’s satellite launch vehicles, consider the following statements :

    1. PSLVs launch the satellites useful for Earth resources monitoring whereas GSLVs are designed mainly to launch communication satellites.

    2. Satellites launched by PSLV appear to remain permanently fixed in the same position in the sky, as viewed from a particular location on Earth.

    3. GSLV Mk III is a four-stage launch vehicle with the first and third stages using solid rocket motors, and the second and fourth stages using liquid rocket engines.

    Which of the statements given above is/are correct?

    Options: (a) 1 only * (b) 2 and 3 (c) 1 and 2 (d) 3 only

     

  • Rashtriya Vigyan Puraskar (RVP)

    Why in the News?

    The Government of India has announced the Rashtriya Vigyan Puraskar as Padma-style national awards for excellence in science, technology, and innovation.

    Key Highlights of 2025 Awards:

    • Vigyan Ratna: Jayant Vishnu Narlikar (posthumously) – astrophysicist and cosmologist known for the Hoyle–Narlikar theory.
    • Vigyan Shri: Eight scientists including Gyanendra Pratap Singh, Yusuf M. Shaikh, K. Thangaraj, Pradeep Thapalil, A.B. Pandit, Venkata Mohan, Mahan Mj, and Jayan N.
    • Vigyan Yuva: Fourteen young scientists across biology, physics, and data science domains.
    • Vigyan Team: CSIR Aroma Mission – for contributions to India’s flavour and fragrance sector, enhancing rural livelihood and agro-innovation.

    About Rashtriya Vigyan Puraskar (RVP):

    • Establishment: Instituted in January 2024 as India’s national Padma-style award for science and technology excellence, recognising scientists, technologists, and innovators of Indian origin, in India or abroad.
    • Purpose: Created to replace legacy awards like the Shanti Swarup Bhatnagar Prize, ensuring transparency, inclusivity, and broader scientific domain coverage.
    • Governing Authority: Administered by the Rashtriya Vigyan Puraskar Committee (RVPC), chaired by the Principal Scientific Adviser (PSA) to the Government of India, comprising 17 members from major science ministries and research councils.
    • Award Calendar:
      • Announcement: Every May 11 on National Technology Day.
      • Conferment: Every August 23 on National Space Day at Rashtrapati Bhavan, by the President of India.
    • Award Categories:
      1. Vigyan Ratna (VR): For lifetime achievement; up to 3 awards annually.
      2. Vigyan Shri (VS): For distinguished contributions; up to 25 awards.
      3. Vigyan Yuva – Shanti Swarup Bhatnagar (VY-SSB): For scientists under 45 years; up to 25 awards.
      4. Vigyan Team (VT): For collaborative research groups (≥ 3 members); up to 3 awards.

    Coverage & Eligibility:

    • Scientific Domains: Thirteen fields including physics, chemistry, biology, mathematics, medicine, engineering, agriculture, space science, and innovation.
    • Eligibility: Open to Indian citizens and Persons of Indian Origin (PIOs); self-nominations not permitted only institutional, departmental, or peer nominations accepted.
    • Award Components: Each recipient receives a Sanad signed by the President, a medallion, and a citation booklet; posthumous awards transferred to next of kin.
    [UPSC 2014] For outstanding contribution to which one of the following’ fields is Shanti Swarup Bhatnagar Prize given?

    Options: (a) Literature (b) Performing Arts (c) Science* (d) Social Service

     

  • Anna Mani and her contributions in India’s Atmospheric Research

    Anna Mani and her contributions in India’s Atmospheric Research

    Why in the News?

    The National Book Trust has released a book on highlighting physicist Anna Mani’s pioneering ozone and pollution studies in Pune decades before “climate change” entered discourse.

    Who was Anna Mani (1918–2001)?

    • Overview: Indian physicist and meteorologist from Peermade, Kerala; pioneered India’s meteorological instrumentation and atmospheric science.
    • Alma mater: Studied physics at Presidency College, Chennai (1939); trained at Imperial College, London; joined IISc Bengaluru under C.V. Raman, publishing five crystallography papers.
    • Professional Career: Joined the India Meteorological Department (IMD) in 1948; later headed its Instruments Division; earned the title “Weather Woman of India.”

    Key Contributions:

    • Meteorological Instrumentation: Designed and standardized 100+ weather instruments, including India’s first pyranometers and sunshine recorders, ending dependence on imports. Established the Regional Instrumentation Centre, Pune, for nationwide calibration.
    • Measurement Infrastructure: Created a national network of solar, wind, and radiation observatories; introduced WMO-grade calibration; data later used for India’s first Wind Energy Atlas.
    • Ozone & Atmospheric Research: In 1964, developed India’s first ozonesonde balloon measuring ozone up to 35 km; integrated into the WMO Global Ozone Mapping Programme. Her studies on ground-level ozone and urban aerosols anticipated modern air-pollution science.
    • Instrument Design & Ethics: Innovated with glass and Teflon components to remove chemical errors in ozonesondes; upheld the credo “wrong measurements are worse than none.” Her Pune lab became a model of scientific precision.
    • Publications: Authored “Handbook for Solar Radiation Data for India” (1980) and “Wind Energy Resource Survey in India” (1992), both still reference standards for renewable-energy studies.
    • Environmental Vision: Warned early about CFC emissions and ozone depletion; connected industrialization to atmospheric alteration, foreshadowing the Anthropocene concept.
    • Legacy: Her datasets form India’s earliest continuous record of ozone, radiation, and aerosol change, anchoring present-day climate-model validation and policy research.
  • RRI technique yields Certified Randomness with one Qubit

    Why in the News?

    The Raman Research Institute (RRI), Bengaluru team has mastered the Leggett–Garg Inequality (LGI)–based quantum randomness certification technique.

    What is Quantum Randomness?

    • Overview: Quantum randomness means true unpredictability, results that even nature or science cannot predetermine. They arise from the laws of quantum physics, not from computer programs or hidden causes.
    • Ordinary Computers: In normal computers, random numbers come from formulas called pseudorandom generators. They look random but can be predicted if someone knows the starting point (the “seed”).
    • Quantum Systems: In quantum physics, when you measure something tiny, like the spin of an electron or the path of a light particle (photon), the result is decided only at the moment of measurement. No one, not even nature, “knows” the answer before that.
    • Why it Matters: True randomness is important for data security, safe online transactions, scientific research, and encryption, where predictability can lead to hacking or errors.

    What has RRI achieved?

    • Discovery: Scientists at the Raman Research Institute (RRI), Bengaluru, led by Prof. Urbasi Sinha, have found a way to create and verify true quantum randomness using a regular cloud-based IBM quantum computer.
    • Why it’s Important: Earlier, proving quantum randomness needed expensive lab equipment. Now it can be done remotely and cheaply, accessible to anyone with internet and quantum cloud access.
    • How it Works: The RRI team used just one qubit (the quantum version of a computer bit) to show that the randomness came from quantum effects, not from hardware noise or computer errors.
    • Key Finding: This demonstrates that even imperfect quantum computers can still generate trustworthy and verifiable random numbers, a capability that classical computers cannot achieve.

    What is the Leggett–Garg Inequality (LGI)–Based Test?

    • Basic Idea: The Leggett–Garg Inequality (LGI) is a scientific test that checks whether something behaves like everyday objects (predictable) or like quantum systems (unpredictable).
    • How it was Used: The RRI scientists measured one qubit at three different times to see if its behavior followed normal physics or quantum rules.
    • Two Conditions Checked:
      • LGI Violation – confirmed the qubit was behaving in a truly quantum way.
      • No Signalling in Time – ensured that each measurement was independent and not influenced by the previous one.
    • Result: Meeting both tests proved that the numbers generated were certified as truly random, coming purely from quantum physics, not from any background noise or interference.

    Real-life Applications:

    • Cybersecurity: Such randomness can make unbreakable encryption keys, protecting sensitive data from hackers.
    • Cloud Computing: People using quantum computers online can now access trusted random numbers for research or secure systems anywhere in the world.
    • Testing Quantum Machines: Helps scientists check the quality of quantum computers, since randomness shows how genuinely quantum the machine is.
    • Better Science: Used in simulations, artificial intelligence, and data analysis where unpredictability makes results more reliable.
    • Big Scientific Message: Confirms that the quantum world is truly uncertain, proving one of the most fascinating truths of modern science, that randomness is built into nature itself.
    [UPSC 2025] Consider the following statements:

    I. It is expected that Majorana 1 chip will enable quantum computing.

    II. Majorana 1 chip has been introduced by Amazon Web Services (AWS).

    III. Deep learning is machine learning.

    How many of the statements given above are correct?

    (a) I and II only (b) II and III only (c) I and III only * (d) I, II and III

     

  • Maitri II Research Station in Antarctica

    Why in the News?

    The Finance Ministry has approved the establishment of Maitri II, India’s newest Antarctic research station, to be built in eastern Antarctica by January 2029.

    About Maitri II Research Station:

    • Objective: Advance research in climatology, glaciology, seismology, biology, and atmospheric sciences while maintaining eco-compliance.
    • Overview: India’s upcoming 4th Antarctic base, to be completed by January 2029 near Schirmacher Oasis, eastern Antarctica, replacing the aging Maitri (1989) which will operate as a summer camp.
    • Implementing Agency: Executed by National Centre for Polar and Ocean Research (NCPOR), Goa under the Ministry of Earth Sciences (MoES); estimated cost ₹2,000 crore.
    • Design & Technology: Features AI-enabled systems, automated sensors, solar and wind power, and upgraded modular accommodation with strict environmental standards.
    • Construction Phases: Prefabrication in India → shipment via Cape Town → transport to Indian Barrier (120 km from Maitri) → on-site assembly during Antarctic summer.

    Back2Basics: India’s Polar Programmes

    • Antarctica Programme: Began in 1981; coordinated by NCPOR.
      • Dakshin Gangotri (1983) – first base, now decommissioned.
      • Maitri (1989) – inland station near Lake Priyadarshini.
      • Bharati (2012) – modern coastal station 3,000 km east.
      • Maitri II (2029) – to be India’s largest and greenest base.
      • Research covers ice-core climate records, marine ecosystems, space weather, and climate modelling.
    • Arctic Programme (2007): Also led by NCPOR; permanent station Himadri at Ny-Ålesund (Svalbard, Norway) studies Arctic warming, polar-monsoon linkages, biodiversity; India holds Observer Status in the Arctic Council (since 2013).

    Key Laws & Treaties governing Polar Expeditions:

    • India Antarctica Act 2022: Implements the Antarctica Treaty (1959); creates Central Committee on Antarctica Governance; bans mining, nuclear activity, non-native species; introduces permit system and Antarctica Fund; severe penalties (up to 20 years).
    • Antarctica Treaty (1959): 54 members (India joined 1983); ensures peaceful scientific use, bans territorial claims and military activity, upholds environmental cooperation.
    • Madrid Protocol (1991): Declares Antarctica a “natural reserve for peace and science”; forbids mineral extraction; mandates Environmental Impact Assessments (EIA).
    • Convention on the Conservation of Antarctic Marine Living Resources (CCAMLR, 1982): Conserves Antarctic marine biodiversity, regulates fishing and resource use to maintain ecosystem balance.
    [UPSC 2015] The term ‘IndARC’, sometimes seen in the news, is the name of Options: (a) an indigenously developed radar system inducted into Indian Defence

    (b) India’s satellite to provide services to the countries of Indian Ocean Rim

    (c) a scientific establishment set up by India in Antartic region

    (d) India’s underwater observatory to scientifically study the Arctic region *

     

  • Indian Army inducts ‘Saksham’ Counter-Unmanned Aerial System (CUAS) Grid

    Why in the News?

    The Indian Army has initiated procurement of ‘Saksham’, an indigenously developed Counter-Unmanned Aerial System (CUAS) Grid, to enhance airspace security and counter emerging aerial threats.

    Indian Army inducts ‘Saksham’ Counter-Unmanned Aerial System (CUAS) Grid
    Visual Representation

    About Saksham Counter-Unmanned Aerial System (CUAS) Grid:

    • Overview: Indigenous counter-drone system developed by the Indian Army with BEL, Ghaziabad, to detect, track, identify, and neutralise unmanned aerial threats.
    • Purpose: Secures the Tactical Battlefield Space (TBS) or Air Littoral—airspace up to 3,000 m (10,000 ft) against low-altitude drones.
    • Origin: Conceived after Operation Sindoor, which revealed gaps in air defence.
    • Acronym: SAKSHAM – Situational Awareness for Kinetic Soft & Hard Kill Assets Management; a Command-and-Control (C2) platform integrating sensors, weapons, and AI analytics to create a Recognised UAS Picture (RUASP).
    • Procurement: Approved under Fast Track Procurement (FTP); aligns with Atmanirbhar Bharat and the Army’s Decade of Transformation (2023–2032).

    Key Features:

    • Detection & Tracking: Continuous surveillance via radar, radio-frequency, and electro-optical/infrared (EO/IR) sensors.
    • AI-Enabled Prediction: Uses AI to forecast hostile activity and suggest counter-responses.
    • Sensor–Weapon Fusion: Integrates jammers, directed-energy systems, and kinetic interceptors for unified action.
    • Automated Command Support: Provides real-time decision aids for threat prioritisation.
    • 3-D Airspace Visualisation: Displays dynamic views of friendly and hostile assets.
    • Network Integration: Runs on the Army Data Network (ADN) and links with Akashteer Air Defence Control for unified airspace management.
    • Mobility & Modularity: Compact, scalable, and rapidly deployable across terrains.
    • Indigenous Focus: Fully designed and produced in India, demonstrating advanced self-reliant defence capability.
    [UPSC 2025] With reference to Unmanned Aerial Vehicles (UAVs), consider the following statements:

    I. All types of UAVs can do vertical landing. II. All types of UAVs can do automated hovering. III. All types of UAVs can use battery only as a source of power supply.

    Which of the statements given above are correct?

    (a) Only one (b) Only two (c) All the three (d) None*

     

  • India’s Dhvani Hypersonic Missile

    Why in the News?

    The DRDO is preparing for the maiden test of the “Dhvani” hypersonic missile.

    About the Dhvani Missile and Its Features

    • Overview: The Dhvani hypersonic missile is being developed by India’s Defence Research and Development Organisation (DRDO) as part of its advanced hypersonic weapons programme.
    • Type: It is designed as a Hypersonic Glide Vehicle (HGV) — a next-generation missile system capable of travelling at hypersonic speeds (beyond Mach 5 or over 7,400 km/h) while performing sharp maneuvers at high altitudes.
    • Range and Speed:
      • Expected operational range: 6,000–10,000 km, potentially doubling the reach of India’s Agni-V ICBM.
      • Speed: Exceeds Mach 5, making interception nearly impossible with current missile defence systems.
    • Flight Mechanism:
      • Launched to extreme altitudes before entering a glide phase in the atmosphere at hypersonic speeds.
      • The glide vehicle can change direction mid-course, allowing unpredictable trajectories that evade radar and anti-missile systems.
    • Design and Engineering:
      • Length: ~9 metres; Width: ~2.5 metres.
      • Blended Wing-Body Configuration: Enhances lift and stability while reducing aerodynamic drag.
      • Thermal Protection System: Uses ultra-high-temperature ceramic composites capable of withstanding 2,000–3,000°C during re-entry.
      • Stealth Features: Angled surfaces and smooth contours minimise radar cross-section, making it virtually undetectable to enemy radars.
    • Development Heritage:
      • Builds upon DRDO’s success with the Hypersonic Technology Demonstrator Vehicle (HSTDV), which validated India’s scramjet propulsion and heat-resistant materials.
      • Represents the transition from technology demonstrator to operational weapon system, signalling India’s arrival in the hypersonic era.

    Comparison with Global Hypersonic Systems:

    System Name Type Speed (Mach) Operational Status
    Russia Avangard HGV 20+ Deployed
    China DF-ZF HGV 10 Deployed
    United States Dark Eagle / HACM Hypersonic Glide / Cruise 8–10 In testing
    India Dhvani (HGV) Hypersonic Glide Vehicle 5–6+ Pre-test stage (2025)

    Strategic Significance for India:

    • Global Standing: Positions India alongside the U.S., Russia, and China in the exclusive club of hypersonic powers, showcasing its advanced defence R&D capacity.
    • Regional Deterrence: Creates a technological and strategic edge over Pakistan and provides a credible counterbalance to China’s hypersonic arsenal.
    • Survivability and Precision: The missile’s speed, stealth, and maneuverability make interception nearly impossible while enabling pinpoint strikes on both land and sea targets.
    • Indigenous Achievement: Developed entirely through Indian expertise, aligning with the Atmanirbhar Bharat vision in critical defence technologies.
    • Force Multiplier: Strengthens India’s nuclear deterrent and strategic triad, ensuring readiness for long-range precision and deterrence missions.
    [UPSC 2014] Which reference to Agni-IV Missile, which of the following statements is/are correct?

    1. It is a surface-to-surface missile.

    2. It is fuelled by liquid propellant only.

    3. It can deliver one-tonne nuclear warheads about 7500 km away.

    Select the correct answer using the code given below:

    (a) 1 only  (b) 2 and 3 only  (c) 1 and 3 only  (d) 1, 2 and 3

     

  • India’s first space observatory AstroSat completes 10 years

    Why in the News?

    AstroSat, India’s first multi-wavelength space observatory has completed 10 years on September 28, 2025, boosting India’s role in multi-messenger astronomy.

    What is Multi-Messenger Astronomy?

    • Overview:  A modern approach that uses different cosmic messengers to study the universe, not just light.
    • Messengers:
      • Light (photons): Radio, visible, UV, X-ray, gamma rays.
      • Gravitational waves: From black hole/neutron star mergers.
      • Neutrinos: From nuclear reactions in stars.
      • Cosmic rays: Charged particles from space.
    • Insights: Light shows stellar surfaces; Gravitational waves show collisions; Neutrinos probe stellar interiors.
    • Example: 2017 neutron star collision observed with both light and gravitational waves, proving origin of heavy elements like gold.
    • AstroSat’s Role: Enabled simultaneous UV, optical, and X-ray observations, tracking flares, black holes, and neutron stars.

    What is AstroSat?

    • Overview: India’s first dedicated multi-wavelength space observatory, launched on September 28, 2015 by PSLV-C30 from Sriharikota.
    • Objective: To study celestial sources simultaneously in X-ray, ultraviolet (UV), and optical bands, unlike most single-band missions.
    • Management: Controlled by the Mission Operations Complex (MOX), ISTRAC, Bengaluru.
    • Mission Life: Designed for 5 years but operational even after 10 years.
    • Payloads:
      • UVIT (Ultra Violet Imaging Telescope).
      • LAXPC (Large Area X-ray Proportional Counter).
      • CZTI (Cadmium-Zinc-Telluride Imager).
      • SXT (Soft X-ray Telescope).
      • SSM (Scanning Sky Monitor).

    Its Accomplishments:

    • Extended Life: Surpassed design life; still generating data.
    • Black Hole Studies: Captured 500+ black hole births, advancing high-energy astrophysics.
    • Galaxy Detection: Tracked extreme UV light from a galaxy 9.3 billion light-years away, aiding early universe studies.
    • Gamma-Ray Bursts: 500+ bursts studied by CZTI.
    • Discoveries: Identified rare UV-bright Milky Way stars, thousands of times brighter than the Sun.
    [UPSC 2016] With reference to ‘Astrosat’,’ the astronomical observatory launched by India, which of the following statements is/are correct?

    1. Other than USA and Russia, India is the only country to have launched a similar observatory into space.

    2. Astrosat is a 2000 kg satellite placed in an orbit at 1650 km above the surface of the Earth.

    Select the correct answer using the code given below.

    (a) 1 only (b) 2 only (c) Both 1 and 2 (d) Neither 1 nor 2*