Relevance: UPSC GS Paper III: Space technology, nuclear technology and scientific developments
Prelims: RTG | RHU | Plutonium-238 | Fission Reactor | Nuclear Thermal Propulsion | Nuclear Electric Propulsion | Outer Space Treaty | Liability Convention | COPUOS | IAEA
Mains: Space Nuclear Safety | Deep-space Exploration | International Liability | Harmful Contamination | Technology Governance | Responsible Space Exploration | International Cooperation
Why in News?
Countries are developing nuclear-energy systems for deep-space missions and permanent bases on the Moon and Mars. This has raised concerns regarding launch accidents, radioactive contamination, international liability and whether existing space laws adequately cover high-power reactors and nuclear propulsion.
Why is Nuclear Power Needed in Space?
Solar power remains the main energy source for spacecraft, but it has limitations:
- sunlight weakens with increasing distance from the Sun;
- permanently shadowed lunar regions receive little or no sunlight;
- long lunar nights interrupt solar generation;
- and extreme temperatures and radiation affect solar panels.
Nuclear systems can provide:
- compact and continuous power;
- energy independent of sunlight;
- heat in extremely cold environments;
- and high power for habitats, life support and propulsion.
Radioisotope systems have supported space missions since 1961.
How is Nuclear Energy Used in Space?
Nuclear energy is used through two broad systems: radioisotope systems and fission systems.
Radioisotope Thermoelectric Generators
- RTGs use heat released through the natural decay of radioactive material, usually plutonium-238.
- They convert this heat into electricity.
- They contain no moving parts.
- They can produce electricity and heat for decades.
RTGs have powered:
- Voyager 1 and 2;
- Curiosity rover;
- and Perseverance rover.
The Voyager spacecraft were launched in 1977 for missions expected to last five years but have remained operational for nearly half a century.
Radioisotope Heater Units
- RHUs do not produce electricity.
- They provide heat to prevent instruments and batteries from freezing.
Fission Reactors
- Fission reactors generate heat through a controlled nuclear chain reaction.
- This heat is converted into electricity.
- They provide much higher power than radioisotope systems.
They are suitable for:
- lunar and Martian habitats;
- life-support systems;
- communications;
- scientific equipment;
- and resource extraction.
How Can Nuclear Energy Propel Spacecraft?
Nuclear Thermal Propulsion
- NTP uses a reactor to heat a propellant such as liquid hydrogen.
- The heated propellant is expelled through a nozzle to produce thrust.
- It can provide nearly twice the propellant efficiency of advanced chemical rockets.
Nuclear Electric Propulsion
- NEP converts reactor heat into electricity.
- Electricity accelerates an ionised propellant.
- It provides low thrust but very high efficiency.
- It is suitable for long deep-space journeys.
Shorter journeys to Mars could reduce astronauts’ radiation exposure and allow spacecraft to carry more cargo.
What are the Major Applications?
Deep-space Missions
- Beyond Mars, sunlight becomes too weak for many high-energy missions.
- Nuclear systems can function continuously in dark and cold environments.
- Voyager spacecraft, now more than 20 billion kilometres from Earth, continue to use radioisotope power.
Lunar Exploration
- Permanently shadowed regions near the lunar south pole may contain water ice.
- Nuclear systems can provide reliable energy where sunlight is unavailable.
Long-duration Human Missions
Nuclear energy can support:
- permanent habitats;
- life-support systems;
- communication networks;
- scientific instruments;
- and oxygen and water extraction from lunar soil.
Future Space Economy
Continuous power could support long-term settlements, scientific stations and industrial infrastructure on the Moon and Mars.
What are India’s Plans?
- In 2021, ISRO invited proposals to develop a 100-watt RTG for future deep-space missions.
- India is planning:
- human spaceflight missions;
- an Indian space station;
- deep-space exploration;
- and a future human landing on the Moon.
- NASA has invited ISRO to participate in its Moon Base programme.
- India can contribute to the development of global safety and regulatory standards.
What are Other Countries Planning?
United States
- NASA’s Dragonfly mission to Saturn’s moon Titan is scheduled for launch in July 2028 and will use a radioisotope generator.
- In August 2025, NASA announced plans for a lunar fission system of at least 100 kilowatts, targeted for deployment by the first quarter of financial year 2030.
- An April 2026 White House memorandum proposed:
- 20-kilowatt reactors in orbit by 2028;
- reactors on the Moon by 2030;
- and higher-power systems during the 2030s.
China and Russia
- China and Russia plan to place a reactor on the Moon by the mid-2030s to support their proposed International Lunar Research Station.
How is Space-based Nuclear Power Regulated?
Outer Space Treaty, 1967
The Treaty:
- requires space activities to follow international law;
- prohibits nuclear weapons and other weapons of mass destruction in orbit or on celestial bodies;
- makes States responsible for national space activities, including those of private companies;
- and requires States to avoid harmful contamination of outer space and celestial bodies.
It prohibits nuclear weapons but does not prohibit peaceful nuclear-power systems.
Liability Convention, 1972
The Convention on International Liability for Damage Caused by Space Objects makes the launching State absolutely liable for damage caused:
- on Earth;
- or to aircraft in flight.
Cosmos 954 Incident
- In 1978, the Soviet satellite Cosmos 954 re-entered over northern Canada.
- Radioactive debris from its reactor was scattered over the region.
- Canada sought compensation.
- The dispute was settled in 1981 for C$3 million.
UN Principles on Nuclear Power Sources, 1992
These principles cover:
- safety assessment;
- radiation protection;
- and notification before the re-entry of a nuclear-powered object.
However, they apply mainly to nuclear sources generating electricity for non-propulsive purposes. They do not comprehensively govern nuclear propulsion.
COPUOS–IAEA Safety Framework, 2009
The framework was developed jointly by:
- the UN Committee on the Peaceful Uses of Outer Space; and
- the International Atomic Energy Agency.
It provides guidance on safety during:
- launch;
- operation;
- and the end of a mission.
However, it is not a complete binding regulatory regime.
What are the Major Challenges?
Launch and Re-entry Risks
Nuclear systems must be capable of surviving:
- rocket explosions;
- launch failures;
- accidental re-entry;
- and impact on Earth without releasing radioactive material.
Radiation Protection
- Reactors require shielding and strict operational controls to protect astronauts, equipment and the space environment.
Technological Immaturity
- Nuclear propulsion is still at an early stage and requires extensive testing before regular use.
Plutonium-238 Shortage
- Plutonium-238 is essential for many RTGs.
- Its availability is limited.
- The United States restarted its production in 2015 after a gap of nearly three decades.
High Technical Requirements
Space nuclear systems require:
- specialised materials;
- extensive ground testing;
- secure reactor controls;
- radiation shielding;
- and safe disposal arrangements.
Way Forward
- Common Standards: Develop global standards for design, testing, launch, operation and disposal.
- Update UN Principles: Extend the 1992 principles to cover nuclear propulsion and high-power reactors.
- Binding Rules: Gradually convert voluntary guidance into enforceable international obligations.
- Safety Assessment: Require transparent pre-launch safety and environmental-impact assessments.
- Emergency Cooperation: Establish international notification and response systems for accidents.
- Clear Liability: Define responsibility where governments and private companies jointly conduct missions.
- Safe Disposal: Create rules for decommissioned reactors and radioactive material.
- Technology Cooperation: Share expertise in shielding, containment and accident-resistant reactor design.
- India’s Participation: India should actively contribute through COPUOS and other international platforms.
Conclusion
Nuclear power can enable deep-space exploration, permanent lunar bases and faster human missions where solar power is insufficient. However, technological progress must be supported by strong engineering safeguards, transparent risk assessment and effective international regulation. Global cooperation is essential to ensure that nuclear power serves peaceful exploration without creating unacceptable risks for Earth or outer space.
UPSC PYQ
Q. In India, why are some nuclear reactors kept under “IAEA safeguards” while others are not?
(a) Some use uranium and others use thorium
(b) Some use imported uranium and others use domestic supplies
(c) Some are operated by foreign enterprises and others by domestic enterprises
(d) Some are State-owned and others are privately owned
Answer: (b) Some use imported uranium and others use domestic supplies
Explanation
India has divided its nuclear facilities into civilian and strategic categories.
- Civilian reactors: Reactors using imported uranium or operating under international civil-nuclear cooperation are placed under International Atomic Energy Agency safeguards. The IAEA verifies that their nuclear material and technology are used only for peaceful purposes.
- Strategic reactors: Certain facilities using domestically sourced nuclear material remain outside IAEA safeguards because they may be connected with India’s strategic nuclear programme.
CARE MCQ
Q. Consider the following statements regarding nuclear power in outer space:
- Radioisotope thermoelectric generators produce electricity from heat released through radioactive decay.
- The Outer Space Treaty prohibits nuclear weapons in space but not the peaceful use of nuclear energy.
- The Liability Convention makes a launching State absolutely liable for damage caused by its space object on Earth or to aircraft in flight.
- The 1992 UN Principles comprehensively regulate nuclear propulsion systems.
Which of the statements given above are correct?
(a) 1 and 2 only
(b) 1, 2 and 3 only
(c) 2, 3 and 4 only
(d) 1, 2, 3 and 4
Answer: (b) 1, 2 and 3 only
Explanation
- Statement 1 is correct: RTGs convert heat produced by the natural decay of radioactive material, usually plutonium-238, into electricity. They do not use a controlled nuclear chain reaction.
- Statement 2 is correct: The Outer Space Treaty prohibits nuclear weapons and other weapons of mass destruction in orbit and on celestial bodies. It does not prohibit peaceful nuclear systems used for power, heating or propulsion.
- Statement 3 is correct: Under the Liability Convention, the launching State is absolutely liable for damage caused by its space object on Earth or to aircraft in flight.
- Statement 4 is incorrect: The 1992 UN Principles primarily cover nuclear sources producing electricity for non-propulsive purposes. They do not comprehensively regulate nuclear thermal or nuclear electric propulsion.
Therefore, statements 1, 2 and 3 are correct, making option (b) the correct answer.
FAQs
Q. What is an RTG?
It converts heat from radioactive decay into electricity for spacecraft.
Q. How is an RHU different from an RTG?
An RHU produces heat only, while an RTG produces electricity and heat.
Q. Why is nuclear power useful in deep space?
It works continuously where sunlight is weak or absent.
Q. Does the Outer Space Treaty ban nuclear power?
No, it bans nuclear weapons but permits peaceful nuclear-energy applications.
Q. What is the main regulatory gap?
Existing rules do not fully regulate high-power reactors and nuclear propulsion.
Relevance: UPSC GS Paper II: Constitutional bodies, governance and civil services
Prelims: Union Public Service Commission | Articles 315–323 | Public Service Commission, 1926 | Federal Public Service Commission | Lee Commission | Consolidated Fund of India | Dholpur House | Pratibha Setu | Universal Registration Number
Mains: Constitutional Independence | Merit-based Recruitment | Political Neutrality | Administrative Impartiality | Inclusive Civil Services | Institutional Integrity | Digital Transformation | Equal Opportunity
Why in News?
- The Union Public Service Commission completed 100 years on 1 October 2026.
- India’s first Public Service Commission was constituted on 1 October 1926.
- It evolved from a limited advisory institution under colonial rule into an independent constitutional body responsible for merit-based recruitment to the Union services.
How Did Merit-based Civil-Service Recruitment Evolve?
Beginning of Open Competition
- The Indian Civil Service examination was introduced in London in 1855, replacing the East India Company’s nomination system.
- However, the London-based examination, use of English and emphasis on subjects such as Greek and Latin disadvantaged Indian candidates.
- Satyendranath Tagore cleared the examination in 1863 and joined the ICS in 1864, becoming its first Indian member.
- By 1919, only 78 of the 1,255 ICS officers were Indians.
Nationalist Demands
- The Government of India Act, 1919 provided for establishing a Public Service Commission.
- The ICS examination was conducted in India for the first time at Allahabad in 1922, alongside London.
- The Indian examination centre moved to Delhi in 1928.
- The Lee Commission, 1924, chaired by Arthur Hamilton Lee, recommended the immediate establishment of a statutory Public Service Commission.
Establishment in 1926
- India’s first Public Service Commission was established on 1 October 1926.
- It functioned under the Public Service Commission (Functions) Rules, 1926, framed under the Government of India Act, 1919.
- Sir Ross Barker was its first Chairman.
- It initially had four Members and functioned from Metcalfe House, Delhi.
- Its limited powers attracted criticism, but it created a permanent recruitment institution within India.
How Did UPSC Become a Constitutional Body?
- The Government of India Act, 1935 provided for Federal and Provincial Public Service Commissions.
- In 1937, the institution was renamed the Federal Public Service Commission.
- H.K. Kripalani became its first Indian Chairman in 1947.
- After Independence, the ICS was replaced by the Indian Administrative Service.
- On 26 January 1950, the Federal Public Service Commission became the Union Public Service Commission.
- R.N. Banerjee became its first Chairman under the constitutional system.
The constitutional provisions on Public Service Commissions were moved in the Constituent Assembly by Dr. B.R. Ambedkar on 22 August 1949.
What is the Constitutional Framework Governing UPSC?
The Union and State Public Service Commissions are governed by Part XIV, Articles 315–323 of the Constitution.
- Article 315: Establishes Public Service Commissions for the Union and States and permits a Joint Commission for two or more States.
- Article 316: Provides for the appointment and tenure of the Chairman and Members. UPSC members are appointed by the President.
- Article 317: Provides for removal or suspension by the President. Removal for misbehaviour requires a Supreme Court inquiry.
- Article 318: Empowers the President to regulate the conditions of service of Members and staff.
- Article 319: Restricts government employment after a Member leaves office. The UPSC Chairman is ineligible for further government employment.
- Article 320: Specifies functions relating to examinations, recruitment, promotions and disciplinary matters.
- Article 321: Allows Parliament or a State Legislature to extend the functions of a Public Service Commission.
- Article 322: Charges the Commission’s expenses on the Consolidated Fund of India.
- Article 323: Requires UPSC to submit an annual report to the President. The report and reasons for non-acceptance of its advice are placed before Parliament.
These provisions protect UPSC from political and financial interference.
What are the Functions of UPSC?
Recruitment Through Examinations
UPSC conducts examinations including:
- Civil Services Examination;
- Indian Forest Service Examination;
- Engineering Services Examination;
- Combined Medical Services Examination;
- National Defence Academy and Naval Academy Examination;
- Combined Defence Services Examination;
- and Central Armed Police Forces (Assistant Commandants) Examination.
Recruitment by Selection
- It conducts interviews and recruitment tests for specialist posts requisitioned by Union Ministries and Departments.
Advisory Functions
UPSC advises the government on:
- recruitment rules;
- methods of recruitment;
- promotions through Departmental Promotion Committees;
- induction into the All India Services;
- and disciplinary cases.
During 2023–24, it processed the records of 24,581 officers for promotion, while 532 officers were inducted into the All India Services.
Selection of State Police Chiefs
Since 2012–13, UPSC has empanelled senior IPS officers for appointment as State Directors General of Police/Heads of Police Force, following the Supreme Court’s directions in Prakash Singh v. Union of India.
What were the Major Institutional Reforms?
Examination Reforms
- 1938: Combined competitive examinations commenced.
- 1969: Eighth Schedule languages were introduced as options for Essay and General Studies papers.
- 1979: The three-stage Civil Services Examination—Preliminary, Main and Interview—was introduced.
- 1989: Optical Mark Recognition technology was introduced.
- 1993: A separate Essay paper was added to the Main Examination.
- 2000: Online Recruitment Application system was introduced.
- 2011: Civil Services Aptitude Test was introduced.
- 2013: The Main Examination was restructured with four General Studies papers, including Ethics, Integrity and Aptitude, and one optional subject.
- 2015: CSAT became a qualifying paper with a minimum requirement of 33%.
- 2021: Women were admitted to the NDA and Naval Academy Examination for the first time.
- 2022: Four Group A railway services were unified as the Indian Railway Management Service.
Important Institutional Milestones
- 1966: Indian Forest Service was created as the third All India Service.
- 1992: Rose Millian Bathew Kharbuli became UPSC’s first woman Chairperson.
- 2016: UPSC Museum was opened.
- 2019: A dedicated control room was established for continuous examination monitoring.
How has UPSC Promoted Inclusion?
Women’s Representation
- Women constituted 3.6% of recommended candidates in 1952.
- In the Civil Services Examination 2025, women constituted 31.2% of selected candidates.
- Women secured 11 of the top 25 ranks in 2025.
- Kiran Bedi became the first woman selected for the IPS in 1972.
Scheduled Castes and Scheduled Tribes
- SC candidates recommended increased from 9 in 1955 to 158 in 2025.
- ST candidates recommended increased from 2 in 1956–57 to 73 in 2025.
- SC applications across examinations increased to 4,51,243 in 2023–24.
- ST applications increased to 1,47,106 during the same period.
Persons with Benchmark Disabilities
- PwBD candidates recommended increased from 3 in 2002 to 42 in 2025.
- UPSC introduced scribes for visually impaired candidates in 1994.
- Eligible candidates are provided extra time, preferred examination centres, escorts and interview facilitators.
Linguistic Inclusion
- Candidates can write the Main Examination in languages listed in the Eighth Schedule.
- Candidates may answer the Personality Test in an Indian language with an interpreter provided by UPSC.
Other Inclusion Measures
- Women candidates receive fee exemption.
- The Economically Weaker Sections category was implemented from CSE 2019.
- A separate transgender category was introduced in the Online Recruitment Application system in 2020.
How has Technology Strengthened Examinations?
AI-enabled Facial Authentication
- UPSC piloted AI-based facial authentication during NDA and CDS examinations in September 2025.
- It was implemented at scale during the Civil Services Preliminary Examination on 24 May 2026.
- Around 5.50 lakh candidates were authenticated through invigilators’ mobile phones.
- Authentication took approximately 6–8 seconds per candidate.
Detection of False Claims
- Analysis of 15 years of candidate data identified and rejected 569 applicants who had furnished false information to claim additional attempts.
Recent Digital Measures
- Universal Registration Number: Introduced in May 2025 as a persistent identity across examinations.
- Randomised interview boards: Introduced from the Combined Medical Services Examination 2025.
- Candidate Helpdesk: A 30-channel call centre introduced from February 2026; it handled over 50,000 calls.
- Provisional answer key: Introduced for the Civil Services Preliminary Examination, with representations accepted through the QPRep portal.
- Online DPC system: A paperless system is being developed for approximately 101 Ministries, Departments and organisations.
- Cybersecurity: Officers are being trained in AI and emerging technologies through NIELIT, while a High-Level Network Committee has been established.
What is Pratibha Setu?
- UPSC introduced the Public Disclosure Scheme in 2018 for willing candidates who cleared all examination stages but narrowly missed the final merit list.
- Their details were made available to interested employers.
- The initiative was revamped as Pratibha Setu on 9 June 2025.
- It connects such candidates with verified employers, including:
- Union Ministries;
- public-sector undertakings;
- autonomous bodies;
- and private organisations.
It ensures that talent beyond the final merit list is not lost.
What Do the Facts and Figures Reveal?
- Total applications increased from 42,727 in 1950–51 to a peak of 45,10,044 in 2022–23.
- Examination centres increased from 8 in 1950 to 86 in 2026.
- Women recommended increased from 3 of 83 candidates in 1952 to 299 of 958 in 2025.
- Disciplinary cases advised upon increased from 53 in 1950–51 to 446 in 2023–24.
- In 2022–23, UPSC conducted 15 examinations, receiving over 33.51 lakh applications.
- It also received 233 requisitions for 4,411 selection posts, attracting more than 11.58 lakh applications.
Conclusion
UPSC’s century-long evolution reflects India’s transition from colonial exclusion to constitutional equality. Its legitimacy rests on merit, impartiality, confidentiality and inclusive access. As technology and administrative needs change, UPSC must continue modernising without weakening these foundational principles. A fair and independent recruitment system remains essential for professional civil services, good governance and public confidence in the Indian state.
CARE MCQ
Q.Consider the following statements regarding the Union Public Service Commission:
- Article 315 provides for Public Service Commissions for the Union and the States.
- A UPSC Member may be removed for misbehaviour by the President after an inquiry by the Supreme Court.
- UPSC’s expenditure is charged on the Consolidated Fund of India.
- UPSC submits its annual report directly to the Chief Justice of India.
Which of the statements given above are correct?
(a) 1 and 2 only
(b) 1, 2 and 3 only
(c) 2, 3 and 4 only
(d) 1, 2, 3 and 4
Answer: (b) 1, 2 and 3 only
Explanation
- Statement 1 is correct: Article 315 provides for a Public Service Commission for the Union and for each State. It also permits a Joint State Public Service Commission for two or more States.
- Statement 2 is correct: Under Article 317, the President may remove a UPSC Member for misbehaviour after the Supreme Court conducts an inquiry and recommends removal.
- Statement 3 is correct: Under Article 322, UPSC’s expenditure is charged on the Consolidated Fund of India. This protects its financial independence.
- Statement 4 is incorrect: Under Article 323, UPSC submits its annual report to the President of India, not the Chief Justice of India. The report is subsequently placed before Parliament.
Therefore, statements 1, 2 and 3 are correct, making option (b) the correct answer.
FAQs
Q. When was India’s first Public Service Commission established?
It was established on 1 October 1926.
Q. Which constitutional articles govern UPSC?
Articles 315–323 of the Constitution.
Q. Who appoints the UPSC Chairman and Members?
The President of India.
Q. What is Pratibha Setu?
It connects willing candidates who narrowly miss final selection with verified employers.
Q. Where is UPSC headquartered?
It is headquartered at Dholpur House, New Delhi.
