rchives
(PRELIMS Focus)
SN 2023zkd
Category: SCIENCE AND TECHNOLOGY
Context: Astronomers have observed a new type of supernova triggered by the violent interaction between a massive star and a black hole in a binary system, named SN 2023zkd.
A massive star, at least 10 times the Sun’s mass, was locked in a tight orbit with a stellar-mass black hole. Over years, the black hole’s gravity stripped away the star’s outer hydrogen layer, exposing helium and causing abnormal brightening. As the orbit decayed, the gravitational stress reached a tipping point, leading to a supernova explosion that released more energy in a second than the Sun will emit in its lifetime. The black hole then consumed much of the stellar debris, becoming more massive.
This is the first strong evidence that black holes can directly trigger supernovae in massive stars, not just influence them through accretion or mergers. It reshapes our understanding of how massive stars die and how black holes grow.
The event was detected thanks to an AI-based system, which flagged unusual activity and prompted rapid follow-up observations. Archival data showed years of brightening prior to the explosion, confirming the gradual mass transfer process.
The discovery highlights the role of black holes in catalyzing stellar deaths, the power of AI in astronomy, and provides new insights into the complex evolution of binary star systems.
Learning Corner:
Supernova
A supernova is the catastrophic explosion of a star, resulting in a sudden, extremely bright outburst that may briefly outshine an entire galaxy.
It represents the final evolutionary stage of certain stars and plays a critical role in enriching the interstellar medium with heavy elements (like iron, gold, uranium).
Supernovae are key to the cosmic cycle of matter and are important markers for measuring cosmic distances (Type Ia).
Types of Supernovae
Type I Supernova
Occurs in binary star systems, where a white dwarf accretes matter from its companion until it reaches the Chandrasekhar limit (~1.4 solar masses).
Results in a thermonuclear explosion with no hydrogen lines in spectrum.
Subtypes:
Type Ia – Used as “standard candles” in cosmology for distance measurement.
Type Ib and Ic – Collapse of massive stars stripped of hydrogen (Ib) and both hydrogen + helium (Ic).
Type II Supernova
Results from the core-collapse of a massive star (> 8 solar masses) after nuclear fuel exhaustion.
Spectrum shows strong hydrogen lines.
Produces either a neutron star or a black hole.
Significance
Enriches galaxies with heavier elements (stellar nucleosynthesis).
Creates neutron stars, pulsars, or black holes.
Provides tools to study dark energy and cosmic expansion (Type Ia).
SN 2023zkd: A New Class of Supernova
Discovery & Uniqueness:
Detected in July 2023 by the Zwicky Transient Facility, SN 2023zkd was not a typical stellar explosion. It is believed to be the strongest evidence of a black hole–triggered supernova, caused by the gravitational interaction between a massive star and its black hole companion.
AI-based Early Detection:
An AI system (Lightcurve Anomaly Identification and Similarity Search – LAISS) flagged its unusual light pattern months in advance, enabling astronomers to track the event in detail.
Strange Pre-Explosion Behavior:
The star displayed four years of continuous brightening before its final detonation, a highly unusual precursor not seen in ordinary supernovae.
Double-Peaked Light Curve:
Instead of one brightness peak, SN 2023zkd showed two separate re-brightening events after explosion—likely from the blast colliding with earlier ejected gas and then with more distant material.
Cause of Explosion:
Scientists suggest that as the star orbited closer to the black hole, intense gravitational stress stripped its mass and eventually triggered the explosion. Another theory is that the black hole shredded the star, and the debris collisions mimicked a supernova. In both cases, the black hole grew more massive.
Scientific Significance:
SN 2023zkd provides a new model of stellar death, showing how compact objects like black holes can induce supernova-like events. It also highlights the growing role of AI in astronomy for early detection and classification of rare cosmic phenomena.
Source: REUTERS
GST reforms
Category: ECONOMICS
Context : S&P Global Ratings has noted that India’s planned GST reforms, despite lowering tax rates and causing an initial revenue loss, are expected to boost long-term revenues by driving higher consumption.
Estimates suggest a shortfall of about ₹85,000 crore initially, but rising demand could eventually add nearly ₹2 lakh crore in revenue.
The reforms—moving towards a simpler two-slab structure of 9% and 18%—are expected to improve compliance, make accounting fairer, and support economic growth. HSBC adds that the GST revamp, along with a possible S&P credit upgrade and changes in global trade tariffs, could strengthen India’s fiscal discipline and investment climate.
The success of these reforms, however, will depend on effective execution, coordination with the GST Council, and adjustments in revenue-sharing arrangements.
Learning Corner:
GST Council
Constitutional Body: Established under Article 279A of the Constitution (via the 101st Constitutional Amendment Act, 2016).
Composition:
Chairperson: Union Finance Minister
Members: Union Minister of State (Finance/Revenue) + Finance Ministers of all States & UTs with legislatures.
Decision-Making:
Decisions taken by 75% majority of weighted votes:
Centre: 1/3rd weightage
States: 2/3rd weightage
Functions:
Recommend GST rates, exemptions, thresholds, model laws, and special provisions for states.
Decide on revenue sharing, dispute resolution, and simplification of compliance.
Importance:
Acts as a federal forum of cooperative federalism, ensuring consensus between Centre and States on indirect taxation.
Key in GST rationalization, rate cuts, and reforms like e-way bills and e-invoicing.
Source: THE INDIAN EXPRESS
Naegleria fowleri
Category: SCIENCE AND TECHNOLOGY
Context: A brain-eating amoeba, has caused the death of a child and infected two others in Kerala’s Kozhikode
The infection, called primary amoebic meningoencephalitis (PAM), is extremely rare but nearly always fatal, with a global fatality rate of about 97%.
The amoeba thrives in warm freshwater such as ponds, lakes, and rivers, and infects people through the nose while swimming—not through drinking water. Symptoms appear within 1–18 days and include headache, fever, nausea, vomiting, altered mental state, and can progress to coma.
There is no proven effective treatment, though drug combinations are attempted and survival is rare. Kerala has reported rising cases, possibly due to unclean water sources and environmental changes, with most infections occurring in children and young people using poorly maintained swimming areas.
Learning Corner:
Naegleria fowleri: The “Brain-Eating Amoeba”
Nature & Habitat:
Naegleria fowleri is a free-living, thermophilic (heat-loving) amoeba found in warm freshwater bodies such as lakes, hot springs, rivers, and poorly maintained swimming pools.
Disease Caused:
It causes Primary Amoebic Meningoencephalitis (PAM), a rare but almost always fatal brain infection.
Mode of Transmission:
Infection occurs when contaminated water enters the body through the nose (not by drinking water). The amoeba travels via the olfactory nerve to the brain, destroying brain tissue.
Symptoms:
Initial – headache, fever, nausea, stiff neck;
Advanced – confusion, seizures, hallucinations, coma. Death usually occurs within 1–2 weeks.
Geographic Presence:
Mostly reported in the USA, South Asia, and other warm climates. Cases are often linked to recreational water exposure in hot weather.
Treatment & Challenges:
No universally effective cure. Drugs like Amphotericin B, miltefosine, and azithromycin have been used in combination therapy with limited success. Early diagnosis is critical but very difficult.
Public Health Importance:
Extremely rare, but high fatality rate (>97%) makes it a serious health concern. Preventive measures include avoiding water entry into the nose during swimming in warm freshwater.
Source: THE INDIAN EXPRESS
Henry Derozio
Category: HISTORY
Context: Personality in news. Can be asked directly in Prelims.
Henry Derozio (1809–1831)
Background: Anglo-Indian poet, teacher, and reformer; appointed as a lecturer at Hindu College, Calcutta, at the age of 17.
Intellectual Role: Inspired students with ideas of liberty, rationalism, equality, and social reform; encouraged questioning of traditions and blind faith.
Young Bengal Movement: His radical students, known as the Derozians or Young Bengal, challenged caste orthodoxy, social inequality, and conservative practices.
Impact: Though Derozio died young at 22, his movement laid an early foundation for modern Indian nationalism, liberalism, and intellectual awakening.
Legacy: Seen as a forerunner of the Bengal Renaissance; his ideals of inclusivity, critical thought, and reform echoed later in the visions of Gandhi, Nehru, and other national leaders.
Source: THE HINDU
Saltwater crocodile
Category: DEFENCE
Context: The saltwater crocodile population in Bengal’s Sundarban Biosphere Reserve has increased significantly compared to 2024, with the latest survey
Estimating 220–242 individuals, including 125 adults, 88 juveniles, and 23 hatchlings. The encounter rate is one crocodile per 5.5 km of surveyed area. This growth reflects effective conservation measures such as systematic surveys, GPS mapping, and the Bhagabatpur breeding facility established in 1976. As apex predators, saltwater crocodiles play a crucial role in maintaining the ecological balance of India’s coastal, mangrove, and riverine ecosystems.
Learning Corner:
Saltwater Crocodile (Crocodylus porosus)
Distribution: Found in India, Southeast Asia, Northern Australia; in India mainly in Sundarbans (West Bengal), Bhitarkanika (Odisha), Andaman & Nicobar Islands.
Habitat: Estuaries, tidal rivers, mangroves, coastal wetlands, and even open seas (excellent swimmers).
Ecological Role: Apex predator, regulates prey populations, maintains food web stability in mangroves and estuarine ecosystems.
Conservation Status:
IUCN Red List: Least Concern (but locally threatened).
Wildlife (Protection) Act, 1972: Schedule I (highest protection).
CITES: Appendix I (trade prohibited).
Threats: Habitat loss (shrinking mangroves), climate change, poaching, human-crocodile conflict.
Conservation Efforts: Breeding programs (e.g., Bhagabatpur Crocodile Project, Odisha’s Bhitarkanika Sanctuary), habitat protection, systematic surveys, GPS mapping.
Sundarban Biosphere Reserve
Location: Covers parts of West Bengal in the delta of the Ganga, Brahmaputra, and Meghna rivers.
Area: ~9,630 sq. km (includes core, buffer, and transition zones).
UNESCO Status: Recognized as a UNESCO Biosphere Reserve (1989) and World Heritage Site (1987).
Unique Feature: World’s largest mangrove forest and the only mangrove habitat of the Royal Bengal Tiger.
Flora & Fauna:
Mangrove species like Sundari (Heritiera fomes), gewa, keora.
Fauna includes Royal Bengal Tiger, saltwater crocodile, fishing cat, estuarine crocodiles, olive ridley turtles, spotted deer, Gangetic dolphins, horseshoe crabs.
Zonation:
Core Area: Sundarban National Park (tiger reserve & critical habitat).
Buffer Zone: Sajnekhali Wildlife Sanctuary and adjoining forests.
Ecological Role: Protects inland areas from cyclones and tidal surges, acts as a carbon sink, and supports coastal biodiversity.
Threats: Rising sea levels, climate change, frequent cyclones, human encroachment, and salinity intrusion.
Conservation Initiatives: Project Tiger, crocodile breeding at Bhagabatpur, mangrove afforestation, community-based eco-development.
Source: THE HINDU
(MAINS Focus)
India’s Persistent Stunting Crisis (GS paper II– Polity and Governance)
Introduction (Context)
Stunting remains one of the most pressing public health and development challenges in India despite decades of interventions.
According to Poshan Tracker (June 2025), 37% of children under five in India are stunted – only a 1% decline from 2016 (38.4%), showing minimal progress despite ambitious targets under POSHAN Abhiyaan.
What is Child Stunting?
Stunting is the impaired growth and development that children experience from poor nutrition, repeated infection, and inadequate psychosocial stimulation.
Children are defined as stunted if their height-for-age is more than two standard deviations below the WHO Child Growth Standards median.
Stunting in children is primarily caused by a combination of poor nutrition, repeated infections, and inadequate psychosocial stimulation, particularly during the critical first 1,000 days of life.
Stunting in early life — particularly in the first 1000 days from conception until the age of two – impaired growth has adverse functional consequences on the child.
It may lead to poor cognition and educational performance, low adult wages, lost productivity and, when accompanied by excessive weight gain later in childhood, an increased risk of nutrition-related chronic diseases in adult life.
In 2018, when POSHAN Abhiyaan was launched, the government had set a target to reduce stunting among children in India by at least 2% points each year.
About POSHAN Abhiyaan
Envisions a “Suposhit Bharat” (Nourished India) by reducing malnutrition and improving nutritional outcomes for women and children.
Acts as a platform for 18 Ministries/Departments to work together. Ensures that nutrition-related schemes across health, sanitation, women empowerment, and food security sectors converge effectively.
Prioritises interventions during the critical window from conception to two years of age.
Aims to reduce stunting, anaemia, and low birth weight.
Target: reduce stunting by 2 percentage points per year and achieve 25% stunting by 2022 (Mission 25 by 2022).
Introduced the Poshan Tracker (ICT-based monitoring system) to track nutrition indicators in real time.
Aims to improve accountability, transparency, and evidence-based planning.
Encourages a people’s movement for nutrition involving communities, local bodies, and civil society.
Data
In 2016 38.4% of children under five in India were stunted (NFHS-4 baseline).
As per POSHAN Abhiyaan target, stunting was to decline by 2 percentage points per year, reaching 26.4% by 2022.
Despite ambitious targets, progress has been slower than expected (stunting reduced marginally from 38.4% in 2016 to 37% in 2025).
Reflects systemic issues like poverty, lack of women’s education, sanitation gaps, and uneven Anganwadi capacity.
Factors Behind Persistent Stunting
Maternal Health & Early Pregnancy
Teenage pregnancies remain a major contributor, with 7% of women aged 15–19 having begun childbearing (NFHS-5, 2019-21).
Adolescent mothers are physically not prepared for healthy pregnancies, leading to low-birth-weight babies who are more vulnerable to growth failures.
Early motherhood also reduces the ability of young women to care for infants adequately, creating an intergenerational cycle of malnutrition.
Maternal Education
Education of mothers has a direct impact on child nutrition.
Data shows that 46% of children born to uneducated mothers are stunted, compared to only 26% among children of mothers with 12+ years of schooling.
Educated mothers are more likely to access antenatal care, adopt balanced nutrition, and delay early pregnancies, leading to healthier children.
Anaemia & Maternal Nutrition
57% of women (15–49 years) and 67% of children under five are anaemic (NFHS-5).
Poor maternal health results in inadequate foetal growth, which manifests as low-birth-weight babies.
Inadequate intake of micronutrients, especially iron and folic acid, further deepens the malnutrition crisis.
Infant Feeding Practices
Only 64% of babies under 6 months are exclusively breastfed in India.
High rate of C-section deliveries (22% in 2021) disrupts early breastfeeding, depriving infants of colostrum—the nutrient-rich first milk crucial for immunity.
Further salaried women in formal jobs often have maternity leave benefits, women in the informal sector (domestic workers, daily wage earners) often resume work within weeks, cutting short breastfeeding and proper child care.
Quality of Diet
Merely 11% of children under 2 years receive a minimum acceptable diet
Most poor households consume carbohydrate-heavy meals (rice, wheat) with low protein and micronutrient intake.
Some states have introduced eggs in Anganwadi meals, but coverage is uneven, and dietary diversity remains poor.
Sanitation & Water
Despite progress under Swachh Bharat Mission, 19% of households still practice open defecation (2019–21).
Contaminated water and poor sanitation cause repeated diarrhoea and gut infections, reducing the body’s ability to absorb nutrients.
A vicious cycle emerges as malnourished children fall ill more often, illness further reduces food absorption, and this worsens malnutrition.
Way Forward
Strengthen Maternal & Adolescent Health by providing universal access to adolescent health programmes.
Delay age of marriage and pregnancy.
Expand iron-folic acid and micronutrient supplementation.
Ensure universal secondary education for girls.
Promote schemes like Beti Bachao Beti Padhao with focus on nutrition and reproductive health.
Enforce maternity benefits for informal sector workers.
Promote early breastfeeding and diversify ICDS/Anganwadi meals with protein-rich foods (milk, eggs, pulses).
Strengthen Swachh Bharat Mission beyond toilet construction.
Ensure piped drinking water through Jal Jeevan Mission.
Encourage decentralised nutrition planning.
Strengthen Anganwadi worker training and community-based nutrition education.
Conclusion
Stunting in India is not just a health issue but a reflection of deep-rooted social, economic, and governance challenges.
While POSHAN Abhiyaan was ambitious, progress has been sluggish due to structural bottlenecks.
To break the cycle of intergenerational deprivation, India needs a holistic approach integrating maternal health, education, sanitation, poverty alleviation, and dietary diversification. Without addressing these systemic issues, the vision of a malnutrition-free India will remain elusive.
Mains Practice Question
Q Despite ambitious initiatives like POSHAN Abhiyaan, stunting among children under five in India remains alarmingly high. Discuss the key factors contributing to persistent stunting and critically evaluate the effectiveness of POSHAN Abhiyaan in addressing them. (250 words, 15 marks)
Source: Why stunting happens in children and what we can do about it | In Focus podcast – The Hindu
SC’s Success in Increasing Case Disposal Rate: A Blueprint for Judicial Reforms (GS paper II– Polity and Governance)
Introduction (Context)
The Supreme Court of India (SC) recently recorded a remarkable improvement in case disposal rates. Within just 100 days (Nov 2024 – May 2025), it reduced pendency and achieved a case clearance ratio (CCR) above 100%, despite a rising number of fresh filings. This achievement is now seen as a blueprint for other courts in India struggling with judicial backlogs.
Key Achievements (Nov 2024 – May 2025)
In about 100 days, the Supreme Court reduced its pendency in registered matters by 4.83%. Registered cases fell from 71,223 to 67,782.
Including defective cases, the reduction was 2.53%.
35,870 cases disposed vs 33,639 new filings, case clearance ratio is106.6%. This means more cases were disposed than filed.
Average CCR over the past 3 years was 96%, showing a 9% improvement.
Average of 341 cases disposed per day.
Noteworthy because filings had increased by 25% since 2022.
Key Reforms and Strategies
Strengthening Case Verification & Listing
Case verification means checking whether all documents in a case file are complete and correct before it is listed for hearing. This is done by Section 1B (Listing Department).
Collaboration with IIM Bangalore helped in process reengineering.
As a result, the verification rate improved to 228 cases/day (from 184).
The Integrated Case Management and Information System (ICMIS), an online platform, automatically allocates cases to benches. This reduces human interference, prevents bias, and saves time.
Registrar’s Court Reintroduction
The Registrar’s Court deals with cases having procedural defects (technical mistakes such as missing documents, wrong formatting, or incomplete filings).
Earlier, such cases used to remain pending for months.
By reintroducing this court, defective cases were resolved faster.
Directions were also given to relist unheard cases within 2–3 weeks, ensuring that they don’t remain in limbo indefinitely.
Email Requests for Urgency
Earlier, senior advocates used to orally “mention” urgent cases before judges to seek quick hearings. This gave them undue privilege over ordinary lawyers.
The SC replaced this with a system of email requests for urgent listing.
This reform saved judicial time and created a level playing field for all litigants, regardless of the lawyer’s stature.
Tackling “Unlisted” and Old Cases
An unlisted case is one that has been filed but not scheduled for hearing, often remaining unnoticed for months or years.
The Court found over 16,000 unlisted cases pending.
To clear this backlog, the SC created “Miscellaneous after Notice Days” (Tuesdays & Wednesdays) to deal specifically with admission-stage cases (cases where the Court decides whether to admit or dismiss them).
Outcome:
In just 100 days, 1,025 main + 427 connected miscellaneous cases were disposed of.
In 15 regular days, 500 main + 66 connected old cases were cleared.
This included 376 criminal cases, which helped raise the criminal CCR (Case Clearance Ratio) to 109%.
Differentiated Case Management (DCM)
DCM is a system where cases are classified and handled differently depending on their complexity and urgency.
The Centre for Research and Planning (CRP) (SC’s research wing) analysed over 10,000 cases to identify short, simple, and old matters.
Judges were provided with briefs of cases so that they could be decided faster, leading to average time: 30–45 minutes per case.
This enabled quicker disposal of cases that had been pending for over a decade.
Case Categorisation Framework
A revamped case categorisation system was introduced.
Allows courts to track which types of cases are causing the largest backlogs.
Identifies the government as a major litigant. Ministries can then strengthen their legal cells to resolve disputes faster.
Enables bulk disposal by grouping simple or connected cases together. Example: 500 connected cases (dependent on one main case) were cleared after the main case was resolved.
Technological Integration
The SC is experimenting with Artificial Intelligence (AI) tools under the SUPACE (Supreme Court Portal for Assistance in Court’s Efficiency) programme.
AI is being used for translation & transcription of proceedings and judgments, detecting filing defects automatically and preparing synopses of bulky case records to save judges’ time.
Initial results have been positive, indicating that AI can be a reliable tool to support judicial efficiency (though not to replace judges’ decision-making).
After such initiatives, large backlog of routine matters still pending and Government litigation continues to form a huge chunk of cases.
Way Forward
Institutionalise Differentiated Case Management in all courts.
Strengthen government litigation cells to reduce unnecessary filings.
Expand AI adoption for case screening, drafting synopses, and record management.
Increase judicial strength and infrastructure for sustained case disposal.
Promote Alternative Dispute Resolution (ADR) to reduce inflow of minor disputes.
Conclusion
The SC’s success in increasing its disposal rate and reducing pendency reflects how careful study, data-driven reforms, and commitment of stakeholders can transform judicial efficiency. If replicated across judicial forums, these strategies can significantly strengthen access to justice and credibility of India’s judicial system.
Mains Practice Question
Q Discuss how the recent reforms of the Supreme Court can provide a blueprint for wider judicial reforms across High Courts and subordinate courts. (250 words, 15 marks)
Source: SC success in increasing case disposal rate can serve as blueprint | The Indian Express