Note4Students
From UPSC perspective, the following things are important :
Prelims level: Winter Solstice
Mains level: Summer and Winter Solstice
Yesterday, December 21, was Winter Solstice, the shortest day of the year in the Northern Hemisphere. In the Southern Hemisphere, conversely, it was Summer Solstice, the year’s longest day.
Try this MCQ:
Q.On 21st June, the Sun
(a) Does not set below the horizon at the Arctic Circle
(b) Does not set below the horizon at Antarctic Circle
(c) Shines vertically overhead at noon on the Equator
(d) Shines vertically overhead at the Tropic of Capricorn
Why are the hours of daylight, not the same every day?
- The explanation lies in Earth’s tilt.
- And it’s not just the Earth — every planet in the Solar System is tilted relative to their orbits, all at different angles.
- The Earth’s axis of rotation is tilted at an angle of 23.5° to its orbital plane.
- This tilt — combined with factors such as Earth’s spin and orbit — leads to variations in the duration of sunlight than any location on the planet receives on different days of the year.
Impact of the tilted axis
- The Northern Hemisphere spends half the year tilted in the direction of the Sun, getting direct sunlight during long summer days.
- During the other half of the year, it tilts away from the Sun, and the days are shorter.
- Winter Solstice, December 21, is the day when the North Pole is most tilted away from the Sun.
- The tilt is also responsible for the different seasons that we see on Earth.
- The side facing the Sun experiences day, which changes to night as Earth continues to spin on its axis.
Un-impacted regions
- On the Equator, day and night are equal. The closer one moves towards the poles, the more extreme the variation.
- During summer in either hemisphere, that pole is tilted towards the Sun and the polar region receives 24 hours of daylight for months.
- Likewise, during winter, the region is in total darkness for months.
Celebrations associated with the Winter Solstice
- For centuries, this day has had a special place in several communities due to its astronomical significance and is celebrated in many ways across the world.
- Jewish people call the Winter Solstice ‘Tekufat Tevet’, which marks the start of winter.
- Ancient Egyptians celebrated the birth of Horus, the son of Isis (divine mother goddess) for 12 days during mid-winter.
- In China, the day is celebrated by families coming together for a special meal.
- In the Persian region, it is celebrated as Yalda or Shab-e-Yalda. The festival marks the last day of the Persian month of Azar and is seen as the victory of light over darkness.
- Families celebrate Yalda late into the night with special foods such as ajeel nuts, pomegranates and watermelon, and recite works of the 14th century Sufi poet Hafiz Shirazi.
In Vedic tradition
- In Vedic tradition, the northern movement of the Earth on the celestial sphere is implicitly acknowledged in the Surya Siddhanta.
- It outlines the Uttarayana (the period between Makar Sankranti and Karka Sankranti). Hence, Winter Solstice is the first day of Uttarayana.
Get an IAS/IPS ranker as your 1: 1 personal mentor for UPSC 2024
Attend Now
Note4Students
From UPSC perspective, the following things are important :
Prelims level: Kosi River
Mains level: Floods in India
The Bihar government will try to divert the course of the mighty Kosi River in Bhagalpur district to save an archaeological site discovered recently.
Tap to read more about the Himalayan Drainage System:
Drainage System | Part 3
Kosi River: The Sorrow of Bihar
- The Kosi is a trans-boundary river which flows through Tibet, Nepal and India.
- The river crosses into northern Bihar, India where it branches into distributaries before joining the Ganges near Kursela in Katihar district.
- Its unstable nature has been attributed course changes and the heavy silt it carries during the monsoon season, and flooding in India has extreme effects.
- It is also known as the “Sorrow of Bihar” as the annual floods affect about 21,000 km2 of fertile agricultural lands thereby disturbing the rural economy.
Why change its course?
- Several priceless artefacts have been found at the Guwaradih village in Naugachhia sub-division of Bhagalpur district during the excavation of a mound.
- These items could be 2,500-years-old and could be of interest for historians if conserved.
- The historical sites are facing threats from the Kosi floods.
- The Kosi currently flows around 300-400 metres from the site, while its old course is about two kilometres from the village.
Threats posed by the move
- Environmentalists have warned that changing the Kosi’s course could be disastrous for Bihar as seen in 2008.
- At that time, the river had breached its mud embankments at Kushaha in Nepal.
- The Kosi frequently changes its course naturally. If its course is artificially changed, it will cause floods and erosion in new areas, leading to massive displacement of people.
- It then caused extensive damage to life and property downstream in five densely populated districts of northeast Bihar.
- Some 500 people were killed and four million rendered homeless.
Get an IAS/IPS ranker as your 1: 1 personal mentor for UPSC 2024
Attend Now
Note4Students
From UPSC perspective, the following things are important :
Prelims level: Chillai Kalan
Mains level: Not Much
People in the Kashmir valley are finding unique ways to celebrate the start of ‘Chillai Kalan’, a local term for the 40-day period of harshest winter that begins annually from December 21.
Tap here to read all about:
Festivals, Dances, Theatre, Literature, Art in News
Chillai Kalan
- Chillai Kalan is the coldest 40-day period of harsh winter of winter in the Jammu and Kashmir region.
- It is traditionally defined as a seasonal period of harsh winter accompanied by a change in increase in both frequency and quantity of precipitation usually snow.
- It begins from December 21 and ends on January 31 next year.
- It is followed by a 20-day long Chillai-Khurd (small cold) that occurs between January 31 and February 19 and a 10-day long Chillai-Bachha (baby cold).
- According to Persian tradition, the night of 21st December is celebrated as Shab-e Yalda-“Night of Birth”, or Shab-e Chelleh “Night of Forty”.
Its’ celebration
- In the Persian tradition, the night of December 21, the longest of the year, is celebrated as Shab-e-Yalda (night of birth) or Shab-e-Chelleh.
- Dozens of netizens from Kashmir named it the ‘Pheran Day’, after the long woollen gown worn during the winters in Kashmir.
- Use of a traditional firing pot called Kangri increases.
- Tap water pipelines partially freeze during this period. The Dal Lake also freezes.
- The famous tourist resort of Gulmarg receives heavy snow which attracts skier’s from every part of the world.
Get an IAS/IPS ranker as your 1: 1 personal mentor for UPSC 2024
Attend Now
Note4Students
From UPSC perspective, the following things are important :
Prelims level: Khudiram Bose
Mains level: Various revolutionary activities
Union Home Minister has visited the native village of Bengali revolutionary Khudiram Bose in Midnapore, West Bengal.
One of the youngest leaders of the Independence movement, Khudiram Bose is highly regarded in Bengal for his fearless spirit. He was just 19 when he was hanged!
Who was Khudiram Bose?
- Bose was born in 1889 at a small village in Midnapore district.
- From his adolescent years, he was drawn towards revolutionary activities, being inspired by a series of public lectures given by Sri Aurobindo and Sister Nivedita, when the duo visited Midnapore in the early 1900s.
- In 1905, when Bengal was partitioned, he actively participated in protests against the British.
- At the age of 15, Bose joined the Anushilan Samiti, an early 20th-century organisation that propounded revolutionary activities in Bengal.
- Within a year, he had learnt how to make bombs and would plant them in front of police stations.
Revolutionary activities
- The deciding moment of Bose’s life came in 1908 when he along with another revolutionary, Prafulla Chaki was assigned the task of assassinating the district magistrate of Muzaffarpur, Kingsford.
- Before being transferred to Muzaffarpur, Kingsford was a magistrate in Bengal.
- His tortuous clamping down on revolutionaries had earned him the ire of this young group of nationalists who decided to hurl a bomb on him.
Kingsford’s assassination attempt
- There were multiple attempts to assassinate Kingsford.
- Initially, the plan was to throw the bomb in the court. However, after much deliberation, it was decided to avoid the court since a lot of civilians might get injured.
- Thereafter, on April 30, 1908, Bose threw a bomb on a carriage which he suspected was carrying Kingsford.
- But it turned out that it was carrying the wife and daughter of a barrister named Pringle Kennedy, who lost their lives, as Kingsford escaped.
Arrest and execution
- By midnight the entire town was aware of the incident and the Calcutta police were summoned to catch the duo.
- Bose was arrested from a railway station called Waini where he had reached the next morning after having walked 25 miles.
- Chaki on the other hand, killed himself before he could get arrested.
- As Bose was brought handcuffed to the police station at Muzaffarpur, the entire town crowded around to take a look at the teenaged boy.
- On July 13, 1908, he was finally sentenced to death.
Get an IAS/IPS ranker as your 1: 1 personal mentor for UPSC 2024
Attend Now
Note4Students
From UPSC perspective, the following things are important :
Prelims level: IMAC
Mains level: India's maritime security
India is looking at integrating more countries into coastal radar network IMAC.
What is IMAC?
- The Indian Navy’s IMAC located in Gurugram which was set up after the 26/11 Mumbai terror attacks is the nodal agency for maritime data fusion.
- It functions under the National Maritime Domain Awareness (NMDA) Project.
- The NMDA project was launched in accordance with the vision of PM on SAGAR (Security and Growth for All in the Region).
- The IMAC monitors movement of more than 120,000 ships a year passing through the Indian Ocean.
- The cargo carried by these ships accounts for 66 per cent of world crude oil, 50 per cent of container traffic and 33 per cent of bulk cargo.
- Thus, IMAC performs a very crucial role in collecting shipping information, analysing traffic patterns and sharing the inputs with the user agencies.
Mission SAGAR, unlike other missions, can create confusion with the name and its purpose. Make note of such special cases. UPSC can ask such questions as one liner MCQs.
Expanding IMAC
- It is meant to enable real-time monitoring of the high seas for threats as also expand India’s assistance for capacity building to Indian Ocean littoral states.
- Efforts are in advanced stages to set up coastal radar stations in Maldives, Myanmar and Bangladesh.
- Mauritius, Seychelles and Sri Lanka have already been integrated into the country’s coastal radar chain network.
- Similar plans are in the pipeline with Maldives and Myanmar and discussions are ongoing with Bangladesh and Thailand.
Get an IAS/IPS ranker as your 1: 1 personal mentor for UPSC 2024
Attend Now
Note4Students
From UPSC perspective, the following things are important :
Prelims level: Conjunction in space-phenomena
Mains level: Not Much
After nearly 400 years, Saturn and Jupiter – the two largest planets in our solar system – will be brought closest in the night sky by an astronomical event called the “great conjunction” and popularly referred to as the “Christmas Star”.
Try this PYQ:
What is a coma, in the context of Astronomy?
(a) Bright half of material on the comet
(b) Long tail of dust
(c) Two asteroids orbiting each other
(d) Two planets orbiting each other
What are the Conjunctions?
- A conjunction is not unique to Saturn and Jupiter however, it is the name given to any event where planets or asteroids appear to be very close together in the sky when viewed from the Earth.
- In June 2005 for instance, as a result of the “spectacular” conjunction, Mercury, Venus and Saturn appeared so close together in the sky that the patch of sky where the three planets were could be covered by a thumb.
- Astronomers use the word “great” for the conjunction of Jupiter and Saturn because of the planets’ sizes.
The “Great Conjunction”
- It happens once in about 20 years because of the time each of the planets takes to orbit around the Sun.
- Jupiter takes roughly 12 years to complete one lap around the Sun and Saturn takes 30 years.
- This is because Saturn has a larger orbit and moves more slowly because it is not as strongly influenced by the Sun’s gravitational force as planets that are closer to the Sun.
- As the two planets move along their orbits, every two decades, Jupiter catches up with Saturn resulting in what astronomers call the great conjunction.
A ‘rare alignment’
- Jupiter and Saturn are bright planets and can be typically seen with the naked eye even from cities.
- But during conjunction, they appear to be close to each other, which is what makes the event noteworthy.
- The event will coincide with the winter solstice (shortest day of the year in terms of hours of sunlight received) in the Northern Hemisphere and summer solstice in the Southern Hemisphere.
- This year, however, the event is rare because the planets will come the closest to each other in nearly four centuries; in what astronomer Henry Throop described is a result of a “rare alignment” of the planets.
Get an IAS/IPS ranker as your 1: 1 personal mentor for UPSC 2024
Attend Now
Note4Students
From UPSC perspective, the following things are important :
Prelims level: Koothambalam
Mains level: Keralan Architecture
The renovated Koothambalam of the Sreekrishna temple, Guruvayur, has been selected for the UNESCO Asia-Pacific Award for cultural heritage conservation.
Try this PYQ:
Q. Building ‘Kalyana Mandapas’ was a notable feature in the temple construction in the kingdom of-
(a) Chalukya
(b) Chandela
(c) Rashtrakuta
(d) Vijayanagara
What is Koothambalam?
- Koothambalam meaning temple theatre is a closed hall for staging Koothu, Nangiar koothu and Koodiyattam, the ancient ritualistic art forms of Kerala.
- Koothambalams are said to be constructed according to the guidelines given in chapter 2 of Nātyasāstra of Bharata Muni.
- The stage within the hall is considered to be as sacred as the temple sanctum.
Its’ construction
- It is constructed within the cloister of the Temple; more precisely within the pancaprakaras of the temple. The prescribe location is between the prakaras of bahyahara and maryada.
- In Kerala tradition, it is considered as one among the panchaprasadas of a temple complex.
- Its dimension varies from temple to temple.
- A square platform with a separate pyramidal roof supported by pillars in the centre called natyamandapam is constructed as s separate structure within the large hall of Koothampalam.
- The floor of the hall is divided into two equal halves and one part is for performance (including stage, instruments, green room etc.) and another half for seating audience.
About Guruvayur Temple
- It is a Hindu temple dedicated to the Hindu lord, Guruvayurappan (a four-armed form of the Lord Vishnu), located in the town of Guruvayur in Kerala.
- It is one of the most important places of worship for Hindus in Kerala and is often referred to as Bhuloka Vaikunta (Holy Abode of Vishnu on Earth).
Get an IAS/IPS ranker as your 1: 1 personal mentor for UPSC 2024
Attend Now
Note4Students
From UPSC perspective, the following things are important :
Prelims level: CMS-01
Mains level: Not Much
The Indian Space Research Organisation (ISRO) successfully placed into a transfer orbit India’s 42nd communications satellite, CMS-01, carried onboard the PSLV-C50.
CMS-01
- It is a communications satellite envisaged for providing services in extended C Band of the frequency spectrum and its coverage will include the Indian mainland and the Andaman & Nicobar and Lakshadweep islands, the ISRO.
- The satellite is expected to have a life of over seven years.
- It was injected precisely into its pre-defined sub- geostationary transfer orbit (GTO).
- CMS-01 is considered to be a replacement of the aged satellite GSAT-12. It provides services like tele-education, tele-medicine, disaster management support and Satellite Internet access.
What is GTO?
- A geosynchronous transfer orbit or geostationary transfer orbit (GTO) is a type of geocentric orbit.
- Satellites which are destined for geosynchronous (GSO) or geostationary orbit (GEO) are (almost) always put into a GTO as an intermediate step for reaching their final orbit.
- A GTO is highly elliptic.
- Its perigee (closest point to Earth) is typically as high as low Earth orbit (LEO), while its apogee (furthest point from Earth) is as high as geostationary (or equally, a geosynchronous) orbit.
Get an IAS/IPS ranker as your 1: 1 personal mentor for UPSC 2024
Attend Now
Note4Students
From UPSC perspective, the following things are important :
Prelims level: Icebergs
Mains level: Impact of climate changes on Cryosphere
A research mission is held to find out the impact of a giant floating iceberg A-68s on the wildlife and marine life on a sub-Antarctic island.
Q. How does the cryosphere affect global climate? (CSM 2017)
What are Icebergs?
- An iceberg is a large piece of freshwater ice that has broken off a glacier or an ice shelf and is floating freely in open (salt) water.
- Small bits of disintegrating icebergs are called “growlers” or “bergy bits”.
- Much of an iceberg is below the surface which led to the expression “tip of the iceberg” to illustrate a small part of a larger unseen issue.
- Icebergs are considered a serious maritime hazard, especially for shipping industries.
A-68s
- The iceberg — named A-68s — is travelling at varying speeds depending on local conditions, but at its fastest was travelling about 20 kilometres a day.
- The huge iceberg — the size of the U.S. state of Delaware — has been floating north since it broke away from Antarctica’s Larsen C ice shelf in 2017.
- It is now about 75 kilometres from the island of South Georgia, and scientists are concerned over the risks it poses to the wildlife in the area if it grounds near the island.
- South Georgia is home to colonies of tens of thousands of penguins and 6 million fur seals, which could be threatened by the iceberg during their breeding season.
- The waters near the island are also one of the world’s largest marine protected areas and house more marine species than the Galapagos.
- Destruction by the iceberg will release this stored carbon back into the water and, potentially, the atmosphere, which would be a further negative impact.
Get an IAS/IPS ranker as your 1: 1 personal mentor for UPSC 2024
Attend Now
Note4Students
From UPSC perspective, the following things are important :
Prelims level: Chang E probe
Mains level: Various lunar missions and their success
A Chinese lunar capsule has returned to Earth with the first fresh samples of rock and debris from the moon in more than 40 years.
Try this PYQ:
Q.What do you understand by the term Aitken basin:
(a) It is a desert in the southern Chile which is known to be the only location on earth where no rainfall takes place
(b) It is an impact crater on the far side of the Moon
(c) It is a Pacific coast basin, which is known to house large amounts of oil and gas
(d) It is a deep hyper saline anoxic basin where no aquatic animals are found
Chang’e-5 Probe
- The Chang’e-5 probe, named after the mythical Chinese moon goddess, aims to shovel up lunar rocks and soil to help scientists learn about the moon’s origins, formation and volcanic activity on its surface.
- The goal of the mission is to land in the Mons Rumker region of the moon, where it will operate for one lunar day, which is two weeks long.
- It will collect 2 kg of surface material from a previously unexplored area known as Oceanus Procellarum — or “Ocean of Storms” — which consist of vast lava plain.
- The original mission, planned for 2017, was delayed due to an engine failure in China’s Long March 5 launch rocket.
A big achievement
- The successful mission was the latest breakthrough for China’s increasingly ambitious space programme that includes a robotic mission to Mars and plans for a permanent orbiting space station.
- This return marked China’s third successful lunar landing but the only one to lift off again from the moon.
- It also marked the first time scientists have obtained fresh samples of lunar rocks since the former Soviet Union’s Luna 24 robot probe in 1976.
Significance of the mission
- Rocks found on the Moon are older than any that have been found on Earth and therefore they are valuable in providing information about the Earth and the Moon’s shared history.
- Lunar samples can help to unravel some important questions in lunar science and astronomy, including the Moon’s age, its formation, the similarities and differences between the Earth and the Moon’s geologic features.
- For instance, the shape, size, arrangement and composition of individual grains and crystals in a rock can tell scientists about its history, while the radioactive clock can tell them the rock’s age.
- Further, tiny cracks in rocks can tell them about the radiation history of the Sun in the last 100,000 years.
Get an IAS/IPS ranker as your 1: 1 personal mentor for UPSC 2024
Attend Now
Note4Students
From UPSC perspective, the following things are important :
Prelims level: Mt. Everest
Mains level: Himalayan Orogeny
China and Nepal have announced Mount Everest is 0.86 m taller than the 8,848 m accepted globally so far.
Try this PYQ:
Q.When you travel to the Himalayas, you will see the following:
- Deep gorges
- U-turn river courses
- Parallel mountain ranges
- Steep gradients causing land-sliding
Which of the above can be said to be the evidences for the Himalayas being young fold mountains?
(a) 1 and 2 only
(b) 1, 2 and 4 only
(c) 3 and 4 only
(d) 1, 2, 3 and 4
Scaling a mountains’ height
- The basic principle that was used earlier is very simple and uses only trigonometry which most of us are familiar with, or at least can recall.
- There are three sides and three angles in any triangle. If we know any three of these quantities, provided one of them is a side, all the others can be calculated.
- In a right-angled triangle, one of the angles is already known, so if we know any other angle and one of the sides, the others can be found out.
- This principle can be applied for measuring the height of any object that does not offer the convenience of dropping a measuring tape from top to bottom.
Accuracy issues
- For small hills and mountains, whose top can be observed from relatively close distances, this can give quite precise measurements.
- But for Mount Everest and other high mountains, there are some other complications.
- These again arise from the fact that we do not know where the base of the mountain is.
Measuring against sea level
- Generally, for practical purposes, the heights are measured above mean sea level (MSL). Moreover, we need to find the distance to the mountain.
- This is done through a painstaking process called high-precision levelling. Starting from the coastline, we calculate step by step the difference in height, using special instruments.
- This is how we know the height of any city from mean sea level.
Adjusting gravitation anomaly
- But there is one additional problem to be contended with — gravity. Gravity is different in different places. It means that even sea level cannot be considered to be uniform at all places.
- So, the local gravity is also measured to calculate the local sea level. Nowadays sophisticated portable gravitometers are available that can be carried even to mountain peaks.
Technology solutions
- These days GPS is widely used to determine coordinates and heights, even of mountains.
- But, GPS gives precise coordinates of the top of a mountain relative to an ellipsoid which is an imaginary surface mathematically modelled to represent Earth.
- This surface differs from the mean sea level. Similarly, overhead flying planes equipped with laser beams (LiDAR) can also be used to get the coordinates.
How accurate are China/Nepal’s apprehensions?
- Considering that during 1952-1954, when neither GPS and satellite techniques were available nor the sophisticated gravimeters, the task of determining the height of Mount Everest was not easy.
- Nepal and China have said they have measured Mount Everest to be 86 cm higher than the 8,848 m that it was known to be.
- But these have been explained in terms of geological processes that might be altering the height of Everest. The accuracy of the 1954 result has never been questioned.
- Most scientists now believe that the height of Mount Everest is increasing at a very slow rate. This is because of the northward movement of the Indian tectonic plate that is pushing the surface up.
- Big earthquake, like the one that happened in Nepal in 2015, can alter the heights of mountains. Such events have happened in the past.
Get an IAS/IPS ranker as your 1: 1 personal mentor for UPSC 2024
Attend Now
Note4Students
From UPSC perspective, the following things are important :
Prelims level: Project 17A
Mains level: India's maritime capability
Himgiri, the first of the three stealth frigates being built by Garden Reach Shipbuilders and Engineers (GRSE), Kolkata, under Project 17A for the Navy, was launched into the water.
Try this question:
Q“To be secure on Land, we must be Supreme at Sea”. In this context, discuss why India is primarily a Maritime Nation?
Project 17A
- The coveted ‘Project 17A’ was cleared by the govt back in 2015.
- It involves the building of seven stealth frigates at an estimated cost of Rs 50,000 crore.
- Of these seven, the contract for three frigates was awarded to GRSE while the contract for another four frigates was awarded to Government-owned Mazagon Docks Limited (MDL) which is based in Mumbai.
- These frigates will come armed with advanced state-of-the-art sensors and boast of top-notch stealth features.
- They will represent the most advanced class of major surface warships for the Indian Navy in a decade, also featuring BrahMos supersonic surface-to-surface missiles.
- These will also have torpedoes and rockets to hit submarines and rapid-fire guns to destroy anti-ship missiles as well as a heavy main gun to engage ships and coastal target.
Get an IAS/IPS ranker as your 1: 1 personal mentor for UPSC 2024
Attend Now
Note4Students
From UPSC perspective, the following things are important :
Prelims level: Merger of Black Holes
Mains level: Black holes and gravitation waves
NASA’s Chandra X-ray Observatory shared the images of Galaxy NGC 6240 that contains two supermassive Black Holes in the process of merging.
From astronomers to general space enthusiasts, black holes are a topic of interest for many. If you’re someone who spends a lot of their time researching facts about this region of space-time or watching videos on the same, then you must check out this news.
Galaxy NGC 6240
- The black holes, located in Galaxy NGC 6240 are 3,000 light-years apart and they will drift together to form a larger black hole millions of years from now.
- As per a blog post by the observatory, the merging process began some 30 million years ago
- The pairs of massive black holes in the process of merging are expected to be the most powerful sources of gravitational waves in the Universe.
- Seen as the bright ‘dots’ near the centre of this image, the black holes are just 3,000 light-years apart.
About Chandra X-ray Observatory
- It is a telescope specially designed to detect X-ray emissions from very hot regions of the universe such as exploded stars, clusters of galaxies, and matter around black holes.
- Orbiting at 139,000 km in space, the telescope was launched aboard the Space Shuttle Columbia during STS-93 by NASA in 1999.
Get an IAS/IPS ranker as your 1: 1 personal mentor for UPSC 2024
Attend Now
Note4Students
From UPSC perspective, the following things are important :
Prelims level: Epigenetics
Mains level: Genetics and human health
Researchers have found the cause of vision impairment due to ageing as the accumulation of “epigenetic noise” that disrupts gene expression patterns leading to changes in inherent DNA function
Genetics is an all-time favourite of UPSC. Every year you can find a question in prelims. Try this one from CSP 2020:
Q.Consider the following statements:
- Genetic changes can be introduced in the cells that produce eggs or sperms of a prospective parent
- A person’s genome can be edited before birth at the early embryonic stage.
- Human-induced pluripotent stem cells can be injected into the embryo of a pig.
Which of the statements given above is/are correct?
(a) 1 only
(b) 2 and 3 only
(c) 2 only
(d) 1, 2 and 3
What is Epigenetics?
- Epigenetics is the study of how your behaviours and environment can cause changes that affect the way your genes work.
- Unlike genetic changes, epigenetic changes are reversible and do not change your DNA sequence, but they can change how your body reads a DNA sequence.
- Environmental stimuli can cause genes to be turned off or turned on.
- This determines a cell’s specialization (e.g., skin cell, blood cell, hair cell, liver cells, etc.) as a fetus develops into a baby through gene expression (active) or silencing (dormant); and nurture.
- This normal epigenetic control on our genes can get altered during normal ageing, stress and disease conditions.
Cellular regulators
- The functioning of cells and tissues in our body are controlled by thousands of proteins that regulate various cellular functions.
- These proteins are in turn encoded by the respective genes which are a part of our genome or the cellular DNA.
- Any minor or major changes to our inherited DNA (addition or mutation) can result in altered protein production, which in turn leads to defective cellular functions.
- This forms the basis for many heritable genetic disorders affecting mankind.
A trigger for various inactivities
- Apart from DNA or protein sequence level alterations, there are other biochemical changes that influence and dictate if a gene should be active or inactive in a given cell type.
- For example, the gene that encodes for the insulin protein is present in the exact form, in every cell of the body.
- However, it is allowed to express only in the insulin-secreting beta cells of the pancreas and is kept inactive in the rest of the cells of the body.
- This phenomenon is tightly regulated by a combination of regulatory proteins that changes the expressivity of the gene.
- Also, the histone proteins that bind the DNA and help to compactly wrap it inside the chromosomes can undergo chemical modifications such as methylations and acetylations on different lysine amino acids within the protein.
- These modifications both on the DNA and its associated proteins alter the chromosomal conformations and regulate gene expression.
- These changes can either unwind the DNA and allow gene expression or can compact the DNA and render the genes in the region inactive or silent.
Epigenetics and the human eye
- The human (and mammalian) eye is a remarkable organ in the course of evolution which has allowed us to “see” the external world clearly and in colour.
- Earlier forms, such as microbes and plants, reacted to light in other ways (for absorption and use, such as photosynthesis).
- The front part of the human eye (cornea, lens and the vitreous humour gel) is transparent, colourless and helps focus the incoming light into the retina, helping us see colour.
- It is the retina that sends the message to the brain.
- Its main component, called the retinal ganglion cells (RGC) are the ones that help in this process of sending the message in the form of electrical signals, called neurons or nerve cells.
- Thus, RGCs are the ones that convert optics into electronics.
Get an IAS/IPS ranker as your 1: 1 personal mentor for UPSC 2024
Attend Now
Note4Students
From UPSC perspective, the following things are important :
Prelims level: ATAGS
Mains level: India's capacity building for high mountain warfare
User trials of the indigenous Advanced Towed Artillery Gun System (ATAGS) developed by the Defence Research and Development Organisation (DRDO) will be held very soon.
Try this question for mains:
Q.Discuss why high-altitude warfare is challenging. Also, discuss India’s preparedness for a long-term war.
ATAGS System
- The ATAGS is a 155-mm, 52-calibre artillery gun jointly developed by the DRDO in partnership with Bharat Forge of the Kalyani Group and the Tata Power SED.
- ATAGS has greater than 95% of indigenous content. It set a world record for the longest unassisted projectile range of 48 kilometres.
Its features
- The gun consists of a barrel, breech mechanism, muzzle brake and recoil mechanism to fire 155 mm calibre ammunition with a firing range of 48 km.
- It has an all-electric drive to ensure reliability and minimum maintenance over a long period of time.
- It has advanced features like high mobility, quick deployability, auxiliary power mode, advanced communication system, automatic command and control system with night capability in direct fire mode.
Get an IAS/IPS ranker as your 1: 1 personal mentor for UPSC 2024
Attend Now
Note4Students
From UPSC perspective, the following things are important :
Prelims level: Plasmodium parasite
Mains level: Malaria in India
A not very common type of malaria, Plasmodium Ovale, has been identified in a jawan in Kerala.
Try this PYQ:
Q. Widespread resistance of malarial parasite to drugs like chloroquine has prompted attempts to develop a malarial vaccine to combat malaria.
Why is it difficult to develop an effective malaria vaccine?
(a) Malaria is caused by several species of Plasmodium
(b) Man does not develop immunity to malaria during natural infection
(c) Vaccines can be developed only against bacteria
(d) Man is only an intermediate host and not the definitive host
What is Malaria?
- Malaria is caused by the bite of the female Anopheles mosquito if the mosquito itself is infected with a malarial parasite.
- There are five kinds of malarial parasites — Plasmodium falciparum, Plasmodium vivax (the commonest ones), Plasmodium malariae, Plasmodium ovale and Plasmodium knowlesi.
- Therefore, to say that someone has contracted the Plasmodium ovale type of malaria means that the person has been infected by that particular parasite.
- Malaria is treated with prescription drugs to kill the parasite. Chloroquine is the preferred treatment for any parasite that is sensitive to the drug.
Plasmodium Ovale
- P ovale rarely causes severe illness and there is no need for panic.
- Symptoms include fever for 48 hours, headache and nausea, and the treatment modality is the same as it is for a person infected with P vivax.
- P ovale is no more dangerous than getting a viral infection.
- It is termed ovale as about 20% of the parasitised cells are oval in shape.
Burden of Malaria in India
- In 2018, the National Vector-borne Disease Control Programme (NVBDCP) estimated that approximately 5 lakh people suffered from malaria.
- 63% of the cases were of Plasmodium falciparum.
- The recent World Malaria Report 2020 said cases in India dropped from about 20 million in 2000 to about 5.6 million in 2019.
Get an IAS/IPS ranker as your 1: 1 personal mentor for UPSC 2024
Attend Now
Note4Students
From UPSC perspective, the following things are important :
Prelims level: Digital Voter ID
Mains level: Election reforms
The Election Commission (EC) is keen to make the Elector’s Photo Identity Card or EPIC available in electronic form.
Try this PYQ:
Q.Regarding DigiLocker, sometimes seen in the news, which of the following statements is/are correct?
- It is a digital locker system offered by the Government under Digital India Programme.
- It allows you to access your e-documents irrespective of your physical location.
Select the correct answer using the code given below.
(a) 1 only
(b) 2 only
(c) Both 1 and 2
(d) Neither 1 nor 2
Digital Voter ID Card
- The digital voter card is not expected to look too different from its physical form.
- It will be available as a PDF file and can be downloaded on one’s phone or computer.
- The soft copy may also have a QR code that will carry the voter’s enrolment details such as name and date of birth and address.
- This is still just a proposal and needs to be approved by the Election Commission.
How to avail it?
- To avail this facility, an eligible voter will have to provide her mobile number or email address to the EC machinery at the time of applying for enrolment in the voters’ list.
- Once her name is included in the electoral roll, she will be intimated through an SMS or email.
- The new voter can then download the Voter Card through OTP (One Time Password) authentication.
- Existing voters may have to re-verify their details with the EC (similar to the Bank KYC process) and provide their email or mobile phone number to get their cards in the electronic form.
Benefits offered
- An electronic card will help the EC save costs on printing and distributing a hard copy of EPIC.
- The EC feels that voters too will find it useful to have the PDF file of her voter card on her phone.
- This will do away with the necessity of first producing a voter’s slip on the day of voting.
Get an IAS/IPS ranker as your 1: 1 personal mentor for UPSC 2024
Attend Now
Note4Students
From UPSC perspective, the following things are important :
Prelims level: IoT , AI
Mains level: Internet based applications
In a first, BSNL launches world’s largest NB-IoT to provide connectivity for millions of unconnected machines, sensors and industrial IoT devices across the country.
What is NB-IoT?
- NB-IoT is a Low Power Wide Area (LPWA) technology that works virtually anywhere.
- It will connect many more devices to the Internet of Things and make many new applications a reality.
- It is optimized for applications that need to communicate small amounts of data over long periods of time.
- Since it operates in licensed spectrum, it is secure and reliable providing guaranteed quality of service.
- It connects devices more simply and efficiently on already established mobile networks and handles small amounts of fairly infrequent 2‑way data, securely and reliably.
And the best is, it provides-
- very low power consumption
- excellent extended range in buildings and underground
- easy deployment into the existing cellular network architecture
- network security & reliability
- lower component cost
Back2Basics: Internet of Things (IoT)
- The IoT describes the network of physical objects—“things”—that are embedded with sensors, software, and other technologies for the purpose of connecting and exchanging data with other devices and systems over the Internet.
- The definition of the IoT has evolved due to the convergence of multiple technologies, real-time analytics, AI, sensors, and embedded systems.
- In the consumer market, IoT technology is most synonymous with products pertaining to the concept of the “smart home”, including devices and appliances.
- It supports one or more common ecosystems and can be controlled via devices associated with that ecosystem, such as smartphones and smart speakers e.g. Alexa.
Remember this PYQ?
When the alarm of your smartphone rings in the morning, you wake up and tap it to stop the alarm which causes your geyser to be switched on automatically. The smart mirror in your bathroom shows the day’s weather and also indicates the level of water in your overhead tank. After you take some groceries from your refrigerator for making breakfast, it recognises the shortage of stock in it and places an order for the supply of fresh grocery items. When You step out of your house and lock the door, all lights, fans, geysers and AC machines get switched off automatically. On your way to office, your car warns you about traffic congestion ahead and suggests an alternative route, and if you are late for a meeting, it sends a message to your office accordingly.
In the context of emerging communication technologies, which one of the following terms best applies to the above scenario?
(a) Border Gateway Protocol
(b) Internet of Things
(c) Internet Protocol
(d) Virtual Private Network
Also read:
[Burning Issue] Internet of Things (IoT)
Get an IAS/IPS ranker as your 1: 1 personal mentor for UPSC 2024
Attend Now
Note4Students
From UPSC perspective, the following things are important :
Prelims level: Aurora Borealis
Mains level: Aurora and the science behind
Northern Lights, also known as aurora borealis could be visible in regions such as in the northern parts of Illinois and Pennsylvania in the US.
Try this PYQ:
What is a coma, in the context of Astronomy?
(a) Bright half of material on the comet
(b) Long tail of dust
(c) Two asteroids orbiting each other
(d) Two planets orbiting each other
Aurora
- Auroras occur when charged particles ejected from the Sun’s surface — called the solar wind — enter the Earth’s atmosphere.
- While flowing toward Earth, the fast-moving solar wind carries with it the Sun’s magnetic field, which disrupts the magnetosphere — the region of space around Earth in which the magnetic field of our planet is dominant.
- When the Sun’s magnetic field approaches Earth, the protective magnetic field radiating from our planet’s poles deflects the former, thus shielding life on Earth.
- However, as this happens, the protective fields couple together to form funnels, through which charged solar wind particles are able to stream down to the poles.
- At the north and south poles, the charged particles interact with different gases in the atmosphere, causing a display of light in the sky.
- This display, known as an aurora, is seen from the Earth’s high latitude regions (called the auroral oval), and is active all year round.
Behind the name
- In the northern part of our globe, the polar lights are called aurora borealis or Northern Lights and are seen from the US (Alaska), Canada, Iceland, Greenland, Norway, Sweden and Finland.
- In the south, they are called aurora australis or southern lights and are visible from high latitudes in Antarctica, Chile, Argentina, New Zealand and Australia.
Where is it observed?
- Generally, the auroral oval is usually witnessed far up in the Polar Regions or the high latitude regions of Europe, like in Norway.
- But occasionally, the oval expands, and the lights become visible at lower latitudes.
- This happens during periods of high solar activity, such as the arrival of solar storms.
- Solar activities include solar flares, solar energetic particles, high-speed solar wind and Coronal Mass Ejections (CME).
Get an IAS/IPS ranker as your 1: 1 personal mentor for UPSC 2024
Attend Now
Note4Students
From UPSC perspective, the following things are important :
Prelims level: Various water borne disease
Mains level: Drinking water issues
Over 550 people in Eluru town of Andhra Pradesh’s West Godavari district have been suffering from convulsions, seizures, dizziness and nausea.
Try this PYQ:
Q.Which of the following can be found as pollutants in the drinking water in some parts of India?
- Arsenic
- Sorbitol
- Fluoride
- Formaldehyde
- Uranium
Select the correct answer using the codes given below:
(a) 1 and 3 only
(b) 2, 4 and 5 only
(c) 1, 3 and 5 only
(d) 1, 2, 3, 4 and 5
Eluru illness
- The All India Institute of Medical Sciences (AIIMS) has found traces of lead and nickel in blood samples of 25 victims out of the 45 samples sent by the state government.
- The primary suspicion is on water contamination by heavy metals. Scientists suspect that pesticide or insecticide has seeped into drinking water sources.
- Experts from Hyderabad who collected water, blood, and food samples say there are indications of lead contamination but can confirm this only after detailed test reports.
Possible cause: Water contamination
- Eluru receives water through canals from both Godavari and Krishna rivers.
- The canals pass through agricultural fields where runoff laced with pesticides mixes with water in the canals. Many aspects of the mystery illness have baffled scientists.
- People who only use packaged drinking water have also fallen sick.
Get an IAS/IPS ranker as your 1: 1 personal mentor for UPSC 2024
Attend Now