UPSC Prelims Current Affairs for 21 September 2026

Ophiopogon Japonicus

September 21, 2026

Ophiopogon Japonicus Latest News

Recently, researchers from the Wildlife Institute of India (WII), Dehradun, and the Uluberia Botanical Institute Herbarium recorded the Ophiopogon japonicus in the wild in Arunachal Pradesh for the first time.

About Ophiopogon Japonicus

It is an evergreen perennial herb that grows in dense clumps.
Other names: Commonly known as dwarf lilyturf or mondo grass.
The genus Ophiopogon comprises around 85 species worldwide, of which seven species were previously recorded from India.
It is a perennial and grows primarily in the subtropical biome.
Appearance: It has narrow, grass-like leaves with retroserrulate margin, small white to pale-purple flowers, and blue, berry-like fruits.
Distribution: The plant is native to East Asia and is found in China, Japan, Korea and Nepal, generally at elevations between 200 and 2,800 m.
Applications
- Its tuberous roots are known as Ophiopogonis Radix or Maidong in Chinese and have long been used in traditional Chinese medicine.
- It is reported that O. japonicus polysaccharides (OJPs) have a variety of biological activities, including anti-diabetes, anti-inflammatory, kidney protection, hepatoprotective and immunomodulatory activity.

Source: TOI

Ophiopogon Japonicus FAQs

Q1: What is Ophiopogon Japonicus?

Ans: It is an evergreen perennial herb that grows in dense clumps.

Q2: What are the other names of Ophiopogon Japonicus?

Ans: It is commonly known as dwarf lilyturf or mondo grass.

Khejri Tree

September 21, 2026

Khejri Tree Latest News

Recently, Lok Sabha Speaker has paid respects to Amrita Devi Bishnoi and all the martyrs who laid down their lives for the protection of Khejri trees in Khejadli village of Rajasthan during the 18th century.

About Khejri Tree

Khejri (Prosopis cineraria (L.) Marbride) is considered a sacred tree in Rajasthan.
It is also called jant or janti in areas like Alwar, Sikar, Jhunjhunu,
Khejri is called the state tree of Rajasthan.
Distribution: It is found growing in arid and semi-arid parts of Rajasthan, Gujarat, Haryana, Punjab, Delhi and some parts of southern India.

Features of Khejri Tree

The tree is frost and drought resistant and tolerates extreme temperatures ranging from 40–45 0C in summer to less than 10 0C in winter.
It is capable of growing in areas of rainfall ranging from 100–600 mm.
The tree can withstand the hottest winds, the driest season and stay alive where other plants cannot survive.
It is a deciduous tree with finely divided, feathery leaves and small yellow flowers.
It is known for its adaptability to arid conditions, the tree thrives in dry and sandy soils.

Significance of Khejri Tree

It is a nitrogen-fixing tree which enhances the fertility of the soil.
The fruit is used to make the very popular local dish ‘Sangri’
The bark of this tress is used medicinally for a range of ailments.
It plays a vital role in preserving the ecosystem of arid and semi-arid areas, mainly in the Thar Desert.
Its highly nutritious leaves constitute an important source of fodder for livestock while nutritious pods are valued as vegetables for human beings.

Source: News On Air

Khejri Tree FAQs

Q1: Where do we find Khejri Tree ?

Ans: It is found growing in arid and semi-arid parts of Rajasthan, Gujarat, Haryana, Punjab, Delhi.

Q2: What is the significance of Khejri Tree?

Ans: It is a nitrogen-fixing tree which enhances the fertility of the soil.

Neodymium-Iron-Boron (NdFeB) Magnets

September 21, 2026

Neodymium-Iron-Boron (NdFeB) Magnets Latest News

Neodymium-Iron-Boron (NdFeB) magnets have become the backbone of energy transition and advanced manufacturing.

About Neodymium-Iron-Boron (NdFeB) Magnets

NdFeB magnets are a type of rare-earth permanent magnet composed of an alloy of neodymium (Nd), iron (Fe), and boron (B).
First developed in the early 1980s, they are the strongest commercially available permanent magnets in the world, offering an extraordinary combination of high magnetic energy density, coercivity, and remanence in a compact size.
The chemical formula for the primary magnetic phase in an NdFeB magnet is Nd₂Fe₁₄B — a tetragonal crystalline structure that gives the material its exceptional magnetic properties.
Typically, the composition includes 29-32.5% neodymium, 64-69% iron, and 1.1-1.2% boron.
Their magnetic performance can deteriorate at high temperatures, although specialized grades are designed for higher-temperature applications.
The addition of heavy rare-earth elements like dysprosium (Dy) or terbium (Tb) is common in high-temperature grades to maintain performance above 150°C.
All the NdFeB magnets are prone to corrosion. They will require a form of protective coating. The standard coating is a triple-layer plating of nickel copper nickel (Ni-Cu-Ni).
Applications:
- NdFeB magnets find widespread use in various industries, including electronics, automotive, medical devices, renewable energy, and more.
- In everyday products like headphones, electric motors, sensors, speakers, and generators, NdFeB magnets deliver enhanced performance, underlining their adaptability in modern technology.

News: TH

Neodymium-Iron-Boron (NdFeB) Magnets FAQs

Q1: What are Neodymium-Iron-Boron (NdFeB) magnets?

Ans: NdFeB magnets are rare-earth permanent magnets composed primarily of neodymium, iron, and boron.

Q2: What makes Neodymium-Iron-Boron (NdFeB) magnets significant among permanent magnets?

Ans: They are the strongest commercially available permanent magnets.

Q3: Which magnetic properties contribute to the exceptional performance of Neodymium-Iron-Boron (NdFeB) magnets?

Ans: Their high magnetic energy density, coercivity, and remanence.

Q4: What happens to the magnetic performance of Neodymium-Iron-Boron (NdFeB) magnets at high temperatures?

Ans: Their magnetic performance can deteriorate at high temperatures.

Q5: Which industries widely use Neodymium-Iron-Boron (NdFeB) magnets?

Ans: They are widely used in electronics, automotive, medical devices, and renewable energy.

AASHVAST Lab

September 21, 2026

AASHVAST Lab Latest News

Indian Army to deploy six AASHVAST labs nationwide for mandatory drone and CCTV cybersecurity screening to counter operational vulnerabilities.

About AASHVAST Lab

AASHVAST stands for Assessment and Analysis of Electronic Systems Hardware for Vulnerabilities and Security Threats.
It is a specialized testing and validation system developed to examine military electronics for hidden security weaknesses.
The primary goal is to ensure that critical military systems operate exactly as intended and do not contain unauthorized components or malicious code.
It is developed by the private firm for the Directorate General of Electronics and Mechanical Engineering (DG EME).

Working of AASHVAST Lab

Scale: There are approximately 14 types of vulnerabilities that the labs can detect.
Neutralize Threats: It neutralizes the common threats of enemy interference in Indian drones, preventing them from performing their designated tasks in a contested area.
Inspect Both Software and Hardware: The facility can inspect both hardware and software components used in drones, communication systems, sensors, and other defence equipment.
It examines the software that operates these unmanned aerial vehicles (UAVs) – to identify and eliminate firmware-level vulnerabilities.
Location based Bug Test: The system examines location-based security controls and assesses how a drone would respond to GPS spoofing or jamming by an adversary.
It can scan systems for hidden passwords, embedded keys and remote-access tools. It can also check whether a drone accepts only manufacturer-approved software updates.

Significance of AASHVAST Lab

The launch of AASHVAST Labs marks a major step toward strengthening the cybersecurity and resilience of India’s defence infrastructure.
The facility will help ensure that military drones, sensors, communication systems, and electronic platforms remain secure from hidden vulnerabilities and evolving cyber threats.

Source: IE

AASHVAST Lab FAQs

Q1: What does AASHVAST stand for?

Ans: AASHVAST stands for Assessment and Analysis of Electronic Systems Hardware for Vulnerabilities and Security Threats.

Q2: What is AASHVAST Lab?

Ans: It is a specialized testing and validation system developed to examine military electronics for hidden security weaknesses.

Nevados de Chillán Volcano

September 21, 2026

Nevados de Chillán Volcano Latest News

Chile’s Nevados de Chillán volcano erupted in an eruptive pulse recently, sending ash and volcanic material about 380 metres above the crater.

About Nevados de Chillán Volcano

It is a large composite stratovolcanic complex located in the Southern Volcanic Zone of the Chilean Andes.
It's one of the most active volcanoes in the Ñuble Region of Chile.
This volcanic group is made up of three main peaks that overlap each other.
- The highest peak is Cerro Blanco (also called Volcán Nevado), which stands about 3,212 meters (10,538 feet) tall.
- To the southeast, you'll find Volcán Viejo (also known as Volcán Chillán), which is about 3,089 meters (10,135 feet) high.
- In the middle of these two is Volcán Nuevo.
Documented eruptions date back to the 17th century, while geological deposits preserve evidence of activity dating back thousands of years.
It is particularly known for lava-dome growth, explosions and pyroclastic activity.

News: HT

Nevados de Chillán Volcano FAQs

Q1: What is Nevados de Chillán?

Ans: Nevados de Chillán is a large composite stratovolcanic complex in the Southern Volcanic Zone of the Chilean Andes.

Q2: How many main peaks make up the Nevados de Chillán volcanic group?

Ans: The volcanic group consists of three main overlapping peaks.

Q3: Which is the highest peak of the Nevados de Chillán volcanic group?

Ans: Cerro Blanco, also known as Volcán Nevado, is the highest peak.

Q4: How old is the documented eruptive history of Nevados de Chillán?

Ans: Its documented eruptions date back to the 17th century.

Painganga Wildlife Sanctuary

September 21, 2026

Painganga Wildlife Sanctuary Latest News

Maharashtra’s tiger conservation programme has added a third big cat to the population being established in Painganga Wildlife Sanctuary, with a young tigress shifted to the 325-sq-km sanctuary in Yavatmal district recently.

About Painganga Wildlife Sanctuary

It is located in the Yavatmal district of Maharashtra.
It derives its name from the river Painganga, or Penganaga River (a tributary of the Wardha River), which borders the sanctuary on its three sides.
It encompasses an area of about 325 sq.km.
The sanctuary’s geological formation consists of basaltic rock, which contributes to the thermal mass of the region.
The sanctuary features several ancient rock shelters adorned with petroglyphs, providing insights into the region’s prehistoric human activity.
Flora: It is characterized by its diverse topography, which includes rolling hills, riverine valleys, and dense deciduous forests primarily composed of teak and bamboo.
Fauna:
- The numerous species of fauna sheltered here include Fox, Leopard, Jackal, Hare, Four Horned Antelope, Porcupine, Sambar, Nilgai, Black Buck, Chinkara, and many others.
- It is also a paradise for birdwatchers with numerous species of avifauna like Vulture, Bulbul, Dove, Kingfisher, Cuckoo, Kite, and others.

News: TOI

Painganga Wildlife Sanctuary FAQs

Q1: Where is Painganga Wildlife Sanctuary located?

Ans: It is located in Yavatmal district of Maharashtra.

Q2: From which river does Painganga Wildlife Sanctuary derive its name?

Ans: It derives its name from the Painganga, or Penganga River.

Q3: What type of forests are mainly found in Painganga Wildlife Sanctuary?

Ans: The sanctuary mainly has dense deciduous forests.

Q4: Which two tree species are prominent in the forests of Painganga Wildlife Sanctuary?

Ans: Teak and bamboo are prominent.

Damodar River

September 21, 2026

Damodar River Latest News

River and fishery department experts in West Bengal are still unable to explain why hilsas are frequently found upstream in the Damodar River.

About Damodar River

It is a major river of eastern India and an important part of the Ganges River System.
It flows through the states of Jharkhand and West Bengal.
This river is sometimes called "the Sorrow of Bengal" because it used to cause big floods in the plains of West Bengal.
Course:
- It originates from the Palamau hills of Chota Nagpur Plateau in Jharkhand.
- From its source, the river flows in a southeastern direction, passing through the Chota Nagpur Plateau, a region known for its rich mineral deposits.
- In its lower course, it flows through West Bengal’s plains and is joined by several tributaries.
- It meets the Hooghly River at Shayampur, which is 48 km from Kolkata.
Total Length: 592 km
The Damodar basin is the industrial and mineral heartland of India.
- It traverses the Gondwana coalfields — Jharia, Raniganj, Bokaro, Karanpura and Giridih — which contain the bulk of India's high-grade coking coal reserves, making the valley the foundation of the country's iron, steel and thermal-power industries.
Tributaries: Barakar River, Konar River, Jamunia River, Bokaro River, Sali River, Ghari River, Guaia River, Khadia River, Bhera River.
Damodar Valley Project:
- It is a multipurpose river valley project in eastern India, developed on the Damodar River and its tributaries with objectives including flood control, irrigation and power generation.
- The project is operated by the Damodar Valley Corporation (DVC), an undertaking of the Indian Government established in July 1948.
- It was one of the first major multipurpose river valley projects undertaken in independent India.
- The DVC constructed dams at Tilaiya and Maithon on the Barakar, Konar on the Konar, and Panchet on the Damodar, together with the Durgapur barrage that feeds the Damodar Valley Canal system.

News: SM

Damodar River FAQs

Q1: Which major river system is the Damodar River an important part of?

Ans: It is an important part of the Ganges River System.

Q2: Which two Indian states does the Damodar River flow through?

Ans: Jharkhand and West Bengal.

Q3: Where does the Damodar River originate?

Ans: It originates in the Palamau hills of the Chota Nagpur Plateau in Jharkhand.

Q4: What is the approximate total length of the Damodar River?

Ans: The Damodar River is approximately 592 km long.

Q5: Where does the Damodar River meet the Hooghly River?

Ans: It meets the Hooghly River at Shayampur, about 48 km from Kolkata.

Exercise SLINEX

September 21, 2026

Exercise SLINEX Latest News

The 13th edition of the exercise SLINEX-26 is being conducted at Visakhapatnam.

About Exercise SLINEX

It is a bilateral naval exercise between India and Sri Lanka, which was conceptualised in 2005.
It has strengthened maritime cooperation between the nations over two decades.
Participation: INS Kavaratti, an indigenous Anti-Submarine Warfare Corvette, and INS Jyoti, the Fleet Tanker, will participate from the Indian Navy.
Phases: The exercise commenced with the Harbour Phase, which will be followed by the Sea Phase.
- The Harbour Phase includes professional interactions, cross-deck visits, sharing of best practices, Yoga, sports and cultural activities.
- The subsequent Sea Phase will focus on enhancing operational synergy and interoperability through coordinated activities at sea.
SLINEX has evolved into an important forum for fostering maritime cooperation, interoperability and mutual understanding between the two Navies.
Significance: It is aligned with India’s vision of MAHASAGAR, SLINEX-26 reinforces India’s commitment to a secure, stable and inclusive maritime environment and further consolidates the enduring maritime partnership between India and Sri Lanka.

Source: PIB

Exercise SLINEX FAQs

Q1: Exercise SLINEX is conducted between which two countries?

Ans: India and Sri Lanka

Q2: What is the significance of Exercise SLINEX?

Ans: It has strengthened maritime cooperation between the nations over two decades.

Sulphur

September 21, 2026

Sulphur Latest News

Soaring prices of sulphur which is again linked to the escalating West Asia and Russia-Ukraine conflicts – is impacting the availability of di-ammonium phosphate (DAP), single super phosphate (SSP) and other major complex fertilisers in India.

About Sulphur

Sulphur (identified by the letter S) is a non-metallic chemical element.
Occurrence: It can be found as a pure element or as sulphate or sulphide minerals.
It occurs naturally in the environment and is believed to be the thirteenth most abundant element in the earth’s crust.

Properties of Sulphur

In its pure form, sulfur is a tasteless, odorless, brittle solid with a pale yellow color.
It’s a poor conductor of electricity that doesn’t dissolve in water.
It combines directly with almost all the elements with the exception of gold, platinum and the noble gases.
Distribution: In India it is mainly found in Puga Valley (Jammu & Kashmir), Barren Island of Bay of Bengal, Andhra Pradesh Kerala and Himachal Pradesh.

Uses of Sulphur

Chemical Industries: Sulphur is an essential raw material for many chemical industries and is essentially used for the production of sulphuric acid.
- Sulphuric acid is a strong mineral acid which is used in ore processing, fertilizer manufacturing, oil refining, waste water processing and chemical synthesis.
Other Industries: The powdered form of sulphur produced by sublimation process is generally used in rubber vulcanisation, agricultural dusts, pharmaceutical products and stock feeds.
Sulphur is used as a light-generating medium in the rare lighting fixtures known as “sulphur lamps”.
Sulphur compounds are also used in detergents, fungicides, dyestuffs and agrichemicals.

Source: IE

Sulphur FAQs

Q1: What is Sulphur?

Ans: Sulphur (identified by the letter S) is a non-metallic chemical element.

Q2: Where do we find Sulphur in India?

Ans: In India it is mainly found in Puga Valley (Jammu & Kashmir), Barren Island of Bay of Bengal, Andhra Pradesh Kerala and Himachal Pradesh.

Rebate of State and Central Taxes and Levies (RoSCTL) Scheme

September 21, 2026

Rebate of State and Central Taxes and Levies (RoSCTL) Scheme Latest News

The government may extend the tenure of the Rebate of State and Central Taxes and Levies (RoSCTL) scheme, an export-boosting incentive for the textile sector, beyond September 30, an official aware of the matter said recently.

About Rebate of State and Central Taxes and Levies (RoSCTL) Scheme

It is a significant export incentive framework introduced by the Ministry of Textiles in March 2019.
Objective: To compensate for the State and Central Taxes and Levies in addition to the Duty Drawback Scheme on export of apparel/garments and Made-ups by way of rebate.
It aims to reimburse all embedded State and Central Taxes/Levies for exports of manufactured goods and garments.
These taxes are incurred during the production of garments and made-ups before export.
It has been established as a successor for the old “Rebate of State Levies (RoSL) Scheme.
The difference between the RoSL & RoSCTL Schemes is that under the RoSL Scheme, there was no benefit on the central tax and levies.
But in the RoSCTL scheme, the exporter will get a rebate of both State and Central tax and Levies.

Why is Rebate of State and Central Taxes and Levies (RoSCTL) Scheme Important?

Many taxes (like electricity duty, mandi tax, fuel tax, etc.) get embedded in production costs.
These cannot be claimed through GST or duty drawback.
RoSCTL refunds these leftover taxes, reducing production cost and increasing competitiveness.
It is based on an internationally acceptable principle that taxes and duties should not be exported, to enable a level playing field in the international market for exports.
Hence, not only indirect taxes on inputs are to be rebated or reimbursed, but also other un-refunded State & Central taxes and levies are to be rebated.

Rebate of State and Central Taxes and Levies (RoSCTL) Scheme Features

It provides transferable and sellable duty credit scrips to exporters based on the Free on-board (FOB) value of their exports.
The scrips shall be issued electronically on the Customs system.
The duty credit scrips shall be used for payment of Basic Customs Duty on the import of goods. These scrips shall be freely transferable.
The duty credit available in an e-scrip shall be transferred at a time for the entire amount in the said e-scrip to another person, and transfer of the duty credit in part shall not be permitted.
Validity of e-scrip: The period of validity of the e-scrip, of one year from its creation, shall not change on account of transfer of the e-scrip.
Eligibility: All exporters of garments/apparel and made-ups manufactured in India are eligible to take benefit under this scheme, except entities/IECs under the Denied Entity List of the Directorate General of Foreign Trade (DGFT).
Implementing agency: It is implemented by the Department of Revenue, Ministry of Finance.

News: BS

Rebate of State and Central Taxes and Levies (RoSCTL) Scheme FAQ's

Q1: What is the Rebate of State and Central Taxes and Levies (RoSCTL) Scheme?

Ans: It is an export incentive scheme that provides rebates on embedded State and Central taxes and levies on exported apparel, garments and made-ups.

Q2: Which Ministry introduced the Rebate of State and Central Taxes and Levies (RoSCTL) Scheme?

Ans: The Ministry of Textiles introduced the scheme.

Q3: What is the main objective of the Rebate of State and Central Taxes and Levies (RoSCTL) Scheme?

Ans: Its main objective is to rebate State and Central taxes and levies embedded in the production of exported apparel, garments and made-ups.

Q4: Why is the Rebate of State and Central Taxes and Levies (RoSCTL) Scheme important for exporters?

Ans: It helps refund un-reimbursed taxes and levies embedded in production costs, thereby reducing costs and improving the competitiveness of Indian exports.

Q5: What does Rebate of State and Central Taxes and Levies (RoSCTL) Scheme provide to eligible exporters?

Ans: It provides transferable and sellable duty credit e-scrips.