About Sinhagad Fort :

• Sinhagad, earlier known as ‘Kondhana’, is a fortress located near Pune, Maharashtra.
• According to history, the fort was built 2,000 years ago and it is said that the name Kondana was derived from sage Kaundinya.
• Early inscriptions and carvings suggest it served as a spiritual retreat and strategic outpost for ancient dynasties.
• Mohammed bin Tughalak captured the fort from the Koli tribal chieftain, Nag Naik in 1340 CE.
• In 1496 CE, Malik Ahmad, the founder of the Nizam Shahi dynasty took control of the fort.
• Nearly 200 years later, the Maratha leader Shahaji Bhonsale captured the fort.
• In 1647 CE, Shivaji held the stronghold.
• In 1665 CE, as per the Treaty of Purandar, Shivaji handed over Sinhagad to the Mughals and again captured it in 1670 CE, under the direction of Tanaji Malusare who was Shivaji's favorite general.
• It has witnessed epic battles, including the legendary Battle of Sinhagad in 1670, where valor, sacrifice, and strategy led to an unforgettable victory for the Marathas over the Mughal Army.
• While recouping the fort during Battle of Sinhagad, Malusare lost his life for which Shivaji Maharaj honoured the fort with the name Sinhagad Fort or Lion’s Fort.
• Aurangzeb laid siege to Sinhagad in 1701- 03 CE, but could not hold it for long.
• Finally the British seized the fort from the Marathas in 1818 AD. The fort was later used as a retreat for many European residents of Pune.
• Architecture:
  • It is a marvel of Maratha architecture and engineering.
  • The fort features two main entrances—the Pune Darwaza, facing Pune, and the Kalyan Darwaza, opening towards the Konkan region—both showcasing intricate stonework and strategic placement for enhanced security.
  • It has an advanced water storage system, which includes ancient rainwater harvesting techniques and natural reservoirs that ensure a continuous water supply.
  • The fort has several bastions, ramparts, walls, and gates that enclose its premises.
  • The fort also houses a temple dedicated to Goddess Kali, a brewery, some military sheds and the tombs of Rajaram Chhatrapati (Shivaji’s youngest son) and Tanaji Malusare.

About DART Mission:

• DART (Double Asteroid Redirection Test) was a NASA space probe dedicated to investigating and demonstrating one method of asteroid deflection by changing an asteroid’s motion in space through kinetic impact.
• It was launched in 2021.
• It was the first-ever space mission to demonstrate asteroid deflection by a kinetic impactor.
• It was the world’s first planetary defense technology demonstration.
• It was aimed at finding out whether or not we could redirect the trajectory of a near-Earth object simply by crashing into it.
• The target of DART was a binary asteroid system consisting of a smaller moonlet, Dimorphos, orbiting around a larger asteroid, Didymos.
  • Because the two were linked by gravity, the theory went, knocking little Dimorphos off-kilter would affect both objects.
  • DART spacecraft successfully collided with Dimorphos in 2022.
  • The mission was a success. For the first time, humans have successfully demonstrated the ability to change the motion of an asteroid in space.

About Doomsday Fish:

• The oarfish is commonly known as the “doomsday fish”.
• It is a deep-sea dweller that rarely comes near the surface.
• Scientific Name: Regalecus glesne
• Habitat: They are deep-sea dwellers, thriving most often in the zone least explored by scientists to date: the mesopelagic zone (waters down to 1,000 meters).
• Features:
  • It is known for its long, ribbon-like body that enables the species to float inconspicuously throughout the water column.
  • It also boasts large eyes and foreboding red spines that stick out to form a crown-like cluster.
  • Oarfish is the longest bony fish known to exist in the ocean.
  • They float vertically and use their reflective bodies as a type of camouflage.
  • It is a filter feeder and primarily eats krill, plankton, and other small crustaceans.

Folklore Related to Doomsday Fish:

• In some areas of the world, these creatures are seen as being harbingers of bad news, particularly disasters or destruction.
• The oarfish has the nickname of “Ryugu no tsukai,” or “sea god’s palace messenger,” in Japanese folklore.
• This myth traces back to the 17th century and says that the surfacing of the oarfish is a harbinger of future natural disasters.

About Gurudongmar Lake:

• It is located on the northern-most edge of Sikkim, very close to the Chinese Tibetan border.
• It is one of the highest lakes in the world and in India.
• It is surrounded by snow-covered mountain ranges all around.
• The lake is primarily fed by glaciers and is a source stream for the Tso Lahmu Lake that later forms the source of the Teesta
• It is considered sacred by Buddhists, Sikhs, and Hindus.
• The lake is named after Guru Padmasambhava—also known as Guru Rinpoche—founder of Tibetan Buddhism.
• Guru Padmasambhava visited the lake in the 8th century on the way back from Tibet.
• Even in extreme winters, a part of this lake never freezes.
  • The myth behind this is that Guru Padmasambhava had once touched and consecrated this lake and made it partially frozen throughout the year.

About Sheshnaag-150:

• It is a long-range collaborative attack swarm drone, with autonomous systems capable of deep strikes and saturation attacks.
• It is being developed by NewSpace Research and Technologies (NRT), a Bengaluru-based aerospace startup focusing on AI-driven unmanned systems and swarm robotics.
• Features:
  • It can carry 25-40 kg payload which is sufficient to damage infrastructure, military vehicles or personnel.
  • What sets it apart is its AI-powered swarm tech — multiple drones can team up autonomously to evade defenses and hit targets together.
  • It has an operational range of over 1,000 km.
  • It can stay airborne for over five hours, enabling it to loiter over target areas before executing an attack.
  • It is equipped with real-time surveillance, autonomous target identification, and strike capabilities.
  • It has the ability to operate in GPS-denied environments using visual navigation systems. This ensures that the drone can still reach targets even if satellite navigation signals are jammed during warfare.

About Silent Valley National Park:

• Location: It is located along the southwest corner of the Nilgiris in South India, in Kerala.
• It is one of the last undisturbed tracts of tropical rainforest in India.
• It constitutes the centerpiece of the Nilgiri Biosphere Reserve, sanctified as a World Heritage Site by UNESCO in 2012.
• River: It is nourished by the Kunthipuzha River.
• Vegetation: It has four types of vegetation “West Coast tropical evergreen forest, southern sub-tropical broad-leaved hill forest, montane wet temperature forest, and grasslands.
• Flora:The flora of the valley includes many species of flowering plants, orchids, ferns and fern allies, liverworts, lichens, and algae.
  • Plants of high medicinal value as well as the towering Culinea trees are also found here. 
• Fauna:  It is famous for its population of lion-tailed macaques, Nilgiri langur, Malabar giant squirrel, Indian elephant, tiger, leopard, and gaur (Indian bison).

About Anavaran Portal:

• It has been operational since 2024.
• It has been using satellite data and machine learning to enable Forest Survey of India to issue location alerts on the loss of forest cover to states every 15 days so that targeted field inspections can be carried out.
• Technology Used:
  • The Anavaran alert system is based on the Google Earth Engine (GEE) platform.
  • It uses Sentinel-2 satellite images as input data.
  • For continuous monitoring during cloudy and monsoon seasons, this is further integrated with Sentinel-1 Synthetic Aperture Radar (SAR) data.

Key Facts about Forest Survey of India (FSI)

• It is a premier national organization under the union Ministry of Environment, Forests and Climate Change.
• Mandate: It is responsible for assessment and monitoring of the forest resources of the country regularly. In addition, it is also engaged in providing the services of training, research and extension.
• Established on June 1, 1981, the Forest Survey of India succeeded the "Preinvestment Survey of Forest Resources" (PISFR), a project initiated in 1965 by Government of India with the sponsorship of FAO and UNDP.
• It has been publishing the State of Forest Report on a biennial basis since 1987.
  • State of Forest Report carries out an in-depth assessment of the forest and tree resources of the country based on interpretation of Remote Sensing satellite data and field based National Forest Inventory (NFI).

About National Highways Green Cover Index:

• It is an initiative of National Highways Authority of India.
• It has been prepared in coordination with the National Remote Sensing Centre (NRSC) of the Indian Space Research Organisation (ISRO).
• The initiative aims to provide a scientific and quantitative assessment of green cover within the Right of Way (RoW) along the National Highways network by leveraging advanced space-based technologies.
• Methodology Used:
  • The assessment is derived from chlorophyll content detected through high-resolution satellite sensors, enabling an objective, technology-driven measure of vegetation presence along the left and right sides of the highways.
  • It measures the percentage of land covered with vegetation along highway corridors, including plantations on the left and right sides of the road, as well as in the median wherever feasible.
  • The analysis is conducted for every one-kilometre highway segment using the Normalized Difference Vegetation Index (NDVI) derived from satellite imagery.
• Significance:
  • It offers a robust, reliable, cost-effective, and time-efficient mechanism for macro-level estimation of the green cover along the National Highways.
  • It will enable comparison, ranking, and targeted interventions for improved plantation management.