About Cardamom Cultivation

• It is popularly known as Queen of Spices belonging to the Zingiberaceae family.
• It is native to the evergreen rain forests of Western Ghats in South India.
• It is cultivated mainly in the Southern States viz; Kerala, Karnataka and Tamil Nadu.
• Soil and climate
  • Soil: It is grown in forest loamy soils which are usually acidic in nature with a pH range of 5.0 – 6.5
  • This crop can be grown at an elevation from 600 to 1500 m.
  • Temperature: 10 to 35 degree C
  • Rainfall: 1500 to 4000 mm
  • Growth of cardamom is enhanced, when planted in humus rich soils with low to medium available phosphorus and medium to high available potassium.
• It is used as a flavoring agent and drug in traditional medicine.

Q1) What is Potassium?

It is a highly reactive metal that is soft, silvery-white in appearance, and has a low density. It is so reactive that it must be stored under oil to prevent its rapid oxidation upon exposure to air.It is an alkali metal and is part of the alkali metal group on the periodic table, along with elements such as sodium (Na) and lithium (Li).

Source: North-East monsoon revives hopes of cardamom growers

About Talagirishwara temple

• It is located in Panamalai village of Viluppuram district in TamilNadu, India.
• The temple is constructed on an insignificant small hill watching the Panamalai lake.
• The temple was constructed by Pallava king Narasimhavarman II, popularly known as Rajasimha.
• Features
  • This Seventh Century structure incorporates a Vimana that resembles that of Kailasanatha temple of Kanchipuram.
  • The garbhagriha stocks a Dharalingam and as in Pallava temples of that period, there is a Somaskanda section on the hindmost wall of the shrine.
  • It includes an Ardhamandapam (partial Mandapam).
  • The walls of the Ardhamandapam posts panels of divinities including Brahma with Saraswati and Vishnu with Lakshmi on either flank.
  • The temple faces east and also the garbhagriha is enclosed on all the 3 sides by sub shrines Some more sub shrines and a Mahamandapam (a massive Mandapam) have been added in the later period to the structure.
  • The Vimana is 3 layered and also the high tier has been rebuilt.
  • The typical Pallava mark, pillars with crouching lions, is also found.
• Paintings in the temple
  • The paintings in this temple bear a close resemblance to the paintings in Ajantha and Chithannavasal.
  • The paintings are on the wall of a sub-temple on the northern side of the Talagirishwara (Siva) temple.
  • There is a painting of Lord Shiva with eight hands dancing known as Latathilagabhani, being watched by Goddess Parvathi with her crown and well decorated umbrella.
  • These paintings were older than Chithannavasal paintings.
  • These paintings were created after covering the stonewalls with paste made of limestone and sand. 

Q1) What are the key features of Ajanta cave paintings?

The paintings in the Ajanta Caves primarily depict scenes from the life of the Buddha, Jataka tales (stories of the Buddha's previous lives), and various mythological and narrative themes. They also include images of royalty, court life, and daily activities from the ancient period.

Source: 1,300-year-old Pallava paintings in ruins at Tamil Nadu’s Panamalai

About Ming Dynasty

• The Ming Dynasty ruled China from A.D. 1368 to 1644.
• Known for its trade expansion to the outside world that established cultural ties with the West, the Ming Dynasty is also remembered for its drama, literature, and world-renowned porcelain.
• The Ming dynasty, which succeeded the Yuan (Mongol) dynasty (1206–1368), was founded by a commoner, Zhu Yuanzhang (1328–1398), who established Nanjing as his capital.
• However, nearly fifty years later, the third Ming emperor relocated the capital to Beijing, which has remained China’s main seat of government ever since.
• Governmental Structure:
  • The basic governmental structure established by the Ming was continued by the subsequent Qing (Manchu) dynasty and lasted until the imperial institution was abolished in 1911/12.
  • The civil service system was perfected during the Ming and then became stratified; almost all the top Ming officials entered the bureaucracy by passing a government examination.
  • Affairs in each province were handled by three agencies, each reporting to separate bureaus in the central government.
  • The position of prime minister was abolished. Instead, the emperor took over personal control of the government, ruling with the assistance of the especially appointed Neige, or Grand Secretariat.
• Achievements:
  • The period witnessed unprecedented economic and cultural expansion and the near doubling of China’s population. 
  • Notable Ming achievements include the refurbishment of the Great Wall to its greatest glory, large naval expeditions, vibrant maritime trade, and the rise of a heavily monetized economy.
  • Vital cultural achievements included the production of exceptional—and often colorful—porcelains, paintings, lacquers, and textiles.
  • The Ming Dynasty saw a publishing boom in China, with an avalanche of affordable books being produced for commoners.
• Collapse:
  • The last century of the Ming, however, was besieged by border troubles, crop failure, fiscal instability, and court corruption, leading to an overthrow by Manchu invaders from the north, who took Beijing in 1644.
  • The Ming were succeeded by the Qing (Manchu) dynasty (1644-1911).

Q1) What is porcelain?

Porcelain is a material made from well-chosen porcelain clay or pottery stone through technological processes like proportioning, molding, drying and firing. Although porcelain developed from pottery, the two are different in raw material, glaze and firing temperature; compared with pottery, porcelain has tougher texture, more transparent body and finer luster. 

Source: Book critical of Ming emperor recalled. Xi Jinping didn't like it because…

About Subsurface Water Ice Mapping (SWIM) project

• It aims to locate the best places to access water ice buried under the Martian surface.
• The recently released fourth set of map is the most detailed and accurate ones since the project started in 2017.
• It is led by the Planetary Science Institute in Tucson, Arizona, and managed by NASA’s Jet Propulsion Laboratory in Southern California.
• The project uses data from several NASA missions, such as the Mars Reconnaissance Orbiter (MRO), the 2001 Mars Odyssey, and the defunct Mars Global Surveyor.
• SWIM used two higher-resolution cameras on MRO.
• The Context Camera data was used to improve the maps of the Northern Hemisphere.
• For the first time, the HiRISE (High-Resolution Imaging Science Experiment) data was used to provide the most detailed view of the ice’s edge as close to the equator as possible.
• The first phase of the SWIM project, completed in 2019, focused on the northern hemisphere. The second phase, completed in 2020 which include the southern hemisphere.
• Highlight of the new map
  • The new map includes sightings of so-called “polygon terrain,” where the seasonal expansion and contraction of subsurface ice causes the ground to form polygonal cracks, indicating more ice hidden beneath the surface.

Q1) What is Mars Reconnaissance Orbiter?

The Mars Reconnaissance Orbiter (MRO) is a NASA spacecraft that has been in orbit around Mars since 2006. It is one of the most advanced and versatile spacecraft ever sent to the Red Planet, and its primary mission is to study Mars' atmosphere, climate, and geology.

Source: Unlocking Mars' climate history: New map helps locate ice on Red Planet

About Subsurface Water Ice Mapping (SWIM) project

• It aims to locate the best places to access water ice buried under the Martian surface.
• The recently released fourth set of map is the most detailed and accurate ones since the project started in 2017.
• It is led by the Planetary Science Institute in Tucson, Arizona, and managed by NASA’s Jet Propulsion Laboratory in Southern California.
• The project uses data from several NASA missions, such as the Mars Reconnaissance Orbiter (MRO), the 2001 Mars Odyssey, and the defunct Mars Global Surveyor.
• SWIM used two higher-resolution cameras on MRO.
• The Context Camera data was used to improve the maps of the Northern Hemisphere.
• For the first time, the HiRISE (High-Resolution Imaging Science Experiment) data was used to provide the most detailed view of the ice’s edge as close to the equator as possible.
• The first phase of the SWIM project, completed in 2019, focused on the northern hemisphere. The second phase, completed in 2020 which include the southern hemisphere.
• Highlight of the new map
  • The new map includes sightings of so-called “polygon terrain,” where the seasonal expansion and contraction of subsurface ice causes the ground to form polygonal cracks, indicating more ice hidden beneath the surface.

Q1) What is Mars Reconnaissance Orbiter?

The Mars Reconnaissance Orbiter (MRO) is a NASA spacecraft that has been in orbit around Mars since 2006. It is one of the most advanced and versatile spacecraft ever sent to the Red Planet, and its primary mission is to study Mars' atmosphere, climate, and geology.

Source: Unlocking Mars' climate history: New map helps locate ice on Red Planet

About earthquake swarm

• It is a series of many (sometimes thousands) low-intensity earthquakes without a discernible main shock that can occur over weeks in active geothermal areas.
• When seismic energy piles up inside the Earth and is released in small amounts from certain points, such a series of earthquakes can occur.

What causes swarm sequences?

• Fluid movement:
  • In volcanic environments, this can be fluid released from deeper magma or circulating within active geothermal areas (in volcanic areas such as the Taupō Volcanic Zone).
  • The earthquakes triggered by fluids occur as fault slip on the cracks and faults through which the water is moving.
• Active volcanism:
  • Magma movement can also act as the ‘driving mechanism’ for swarms, creating the earthquakes as magma-filled cracks push their way through the Earth’s crust.
  • In such a case the earthquakes commonly occur near the crack tip (ahead of the magma where the crack is starting to open), or off to the side of the crack.
• Slow-slip events
  • A slow-slip event is essentially an earthquake in slow-motion, and typically involves centimetres to tens of centimetres of movement along a fault, over weeks to years.
  • We commonly see slow slip events at the Hikurangi subduction zone, usually at least one or two per year. 

Key facts about Reykjanes peninsula

• It is a peninsula in South West Iceland, characterized by immense lava fields, volcanoes, and heightened geothermal activity.
• It runs along the Mid-Atlantic Rift, where the Eurasian and the North American tectonic plates are drifting apart. 

Q1) What is Mid-Atlantic Ridge?

It is a major underwater mountain range that runs down the center of the Atlantic Ocean. It is a divergent tectonic plate boundary where the North American Plate and the Eurasian Plate are moving away from each other. This geological feature extends for thousands of kilometers from the Arctic Ocean in the north to the Atlantic Ocean in the south, essentially dividing the Atlantic Ocean into two halves.

Source: Iceland hit by ‘seismic swarm‘ of small earthquakes in volcano warning

About Lower Subansiri Hydroelectric Power Project

• It is the biggest hydroelectric project undertaken in India so far.
• It is a run-of-river scheme on the river Subansiri.
• Location: The Project is located near North Lakhimpur on the border of Arunachal Pradesh and Assam.
• Capacity: 2000MW
• It will generate up to 7.4 billion kWh of electricity annually.
• The project includes the construction of a surface powerhouse and a concrete gravity dam that is 116m-high from the river bed level.
• The length of the dam will be 284m.
• The dam is located in the Dhemaji district of Assam, while the powerhouse is located in the Subansiri district of Arunachal Pradesh.
• It is being developed by the state-run National Hydro Power Corporation (NHPC).
• Funding:
  • The project cost was met through 70% equity and 30% debt financing through the provision of a term loan.
  • The central government is providing budgetary support as part of the equity component.

Key facts about the Subansiri River

• Subansiri River, better known as the "Gold River" is the largest tributary of the Brahmaputra River.
• It flows through Assam, Arunachal Pradesh, and the Tibet Autonomous Region of China. 
• Course:
  • Originating from the Himalaya Mountains, it flows towards the east and south-east portion of Arunachal Pradesh and then flows to Assam Valley.
  • Finally, it joins the Brahmaputra River in Lakhimpur district, Assam.
• It joins the Brahmaputra at the mystic confluence of Majuli Island, which is noted as the largest inhabited river island in the world.
• Total Length: 442 kilometres

Q1) What is a Gravity Dam?

A gravity dam is a dam constructed from concrete or stone masonry and designed to hold back water by primarily utilizing the weight of the material alone to resist the horizontal pressure of water pushing against it.

Source: Landslide blocks diversion tunnel at NHPC's Subansiri hydro project

About NASA-ISRO Synthetic Aperture Radar (NISAR)

• NISAR is a Low Earth Orbit (LEO) observatory jointly developed by NASA and ISRO. 
• It is an SUV-size satellite weighing 2,800 kilograms.
• It consists of both L-band and S-band synthetic aperture radar (SAR) instruments, which makes it a dual-frequency imaging radar satellite.
• NISAR will be the first satellite mission to use two different radar frequencies (L-band and S-band) to measure changes in our planet's surface.
• SAR is capable of penetrating clouds and can collect data day and night regardless of the weather conditions.
• NASA has provided the L-band radar, GPS, a high-capacity solid-state recorder to store data, and a payload data subsystem. ISRO has provided the S-band radar, the GSLV launch system, and spacecraft.
• It also consists of a large 39-foot stationary antenna reflector made of a gold-plated wire mesh which will be used to focus “the radar signals emitted and received by the upward-facing feed on the instrument structure.
• Mission Objectives:
  • It will measure Earth’s changing ecosystems, dynamic surfaces, and ice masses, providing information about biomass, natural hazards, sea level rise, and groundwater.
  • NISAR will observe Earth’s land and ice-covered surfaces globally with 12-day regularity on ascending and descending passes.

Q1) What is a Low Earth Orbit (LEO)?

A low Earth orbit (LEO) is, as the name suggests, an orbit that is relatively close to Earth's surface. It is normally at an altitude of less than 1000 km but could be as low as 160 km above Earth.

Source: NASA-ISRO radar satellite to offer detailed insights into forests and wetlands: Know all about NISAR

About Koyna Dam

• Location: It is one of the largest dams in the state of Maharashtra and is located at Koyna Nagar in Satara district.
• It is a rubble-concrete dam constructed on the Koyna River.
• The construction of this dam was completed in 1963 and is amongst the chief civil engineering projects built after the independence of India.
• The main purpose of dam is hydroelectricity with some irrigation in neighboring areas.
• Koyna Hydroelectric Project is the largest completed hydroelectric power plant in India, with a total installed capacity of 1,920 MW. 
• The catchment area of the Koyna Dam blocks up the Koyna River and creates the Shivsagar Lake, which is roughly 50 km long.
• The dam plays a vital role in flood control during monsoon season.

Key Facts about Koyna River

• It is a tributary of the Krishna River in the western part of Maharashtra.
• Origin: It rises near Mahabaleshwar, a famous hill station in the Western Ghats. 
• The river is just 100 meters wide and flows slowly.
• Unlike most of the other rivers in Maharashtra, which flow East-West direction, the Koyna River flows in North-South direction.
• The river merges with the Krishna River at Karad in the Satara district of Maharashtra.
• Due to its electricity-generating potential through the Koyna Hydroelectric Project, Koyna River is known as the Life Line of Maharashtra. 

Q1) Which are the main tributaries of Krishna River?

The principal tributaries joining Krishna are the Ghataprabha, the Malaprabha, the Bhima, the Tungabhadra and the Musi.

Source: Koyna dam authorities propose water cuts for irrigation, power generation