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Subject: Science and Technology

  • Carbon enrichment of the Universe

    A recent study has provided new insights on the origins of the carbon in our galaxy.

    Try this question from CSP 2016:

    Q.Consider the following:

    1. Photosynthesis
    2. Respiration
    3. Decay of organic matter
    4. Volcanic action

    Which of the above add carbon dioxide to the carbon cycle on earth?

    (a) 1 and 4 only

    (b) 2 and 3 only

    (c) 2, 3 and 4 only

    (d) 1, 2, 3 and 4

    Why study Carbon?

    • Carbon is essential for life: It is the simple building block of all the complex organic molecules that organisms need.
    • It is known that all the carbon in the Milky Way came from dying stars that ejected the element into their surroundings.
    • What has remained debated, however, is what kind of stars made the major contribution.
    • The study shows the analysis of white dwarfs — the dense remnants of a star after its death.

    How does carbon come from stars?

    • Most stars — except the most massive ones — are doomed to turn into white dwarfs.
    • When the massive ones die, they go with a spectacular bang known as the supernova.
    • Both low-mass and massive stars eject their ashes into the surroundings before they end their lives.
    • And these ashes contain many different chemical elements, including carbon.

    How is it synthesized?

    • Both in low-mass stars and in massive stars carbon is synthesized in their deep and hot interiors through the triple-alpha reaction that is the fusion of three helium nuclei.
    • In low-mass stars, the newly synthesized carbon is transported to the surface [from the interiors] via gigantic bubbles of gas and from there injected into the cosmos through stellar winds.
    • Massive stars enrich the interstellar medium with carbon mostly before the supernova explosion, when they also experience powerful stellar winds.

    Findings of the news research

    • It was earlier debated that whether the carbon in the Milky Way originated from low-mass stars before they became white dwarfs or from the winds of massive stars before they exploded as supernovae.
    • The new research suggests that white dwarfs may shed more light on carbon’s origin in the Milky Way.
    • The researchers measured the masses of the white dwarfs, derived their masses at birth, and from there calculated the “initial-final mass relation”.
    • The IFMR is a key astrophysical measure that integrates information of the entire life cycles of stars.
    • They found that the relationship bucked a trend — that the more massive the star at birth, the more massive the white dwarf left at its death.
    • So far, stars born roughly 1.5 billion years ago in our galaxy were thought to have produced white dwarfs about 60-65% the mass of our Sun.

    What explains this?

    • From an analysis of the initial-final mass relation around the little kink, the researchers drew their conclusions about the size range for the stars that contributed carbon to the Milky Way.
    • Stars more massive than 2 solar masses, too, contributed to the galactic enrichment of carbon.
    • Stars less massive than 1.65 solar masses did not. In other words 1.65-Msun [1.65 times the mass of the Sun] represents the minimum mass for a star to spread its carbon-rich ashes upon death.

  • [pib] Mongolian Kanjur Manuscripts

    The Ministry of Culture has taken up the project of reprinting of 108 volumes of Mongolian Kanjur under the National Mission for Manuscripts (NMM).  The first sets of five volumes were presented to the President of India.

    Try this question from CSP 2011:

    Q.India maintained its early cultural contacts and trade links with Southeast Asia across the Bay of Bengal. For this preeminence of early maritime history of Bay of Bengal, which of the following could be the most convincing explanation/explanations?

    (a) As compared to other countries, India had a better ship-building technology in ancient and medieval times.

    (b) The rulers of southern India always patronized traders, Brahmin priests and Buddhist monks in this context.

    (c) Monsoon winds across the Bay of Bengal facilitated sea voyages.

    (d) Both (a) and (b) are convincing explanations in this context.

    Mongolian Kanjur

    • Mongolian Kanjur, the Buddhist canonical text in 108 volumes is considered to be the most important religious text in Mongolia.
    • In the Mongolian language ‘Kanjur’ means ‘Concise Orders’- the words of Lord Buddha in particular. It has been translated from Tibetan.
    • It is held in high esteem by the Mongolian Buddhists and they worship the Kanjur at temples and recite the lines of Kanjur in daily life as a sacred ritual.
    • The Kanjur is kept almost in every monastery in Mongolia.
    • The language of the Kanjur is Classical Mongolian and it is a source of providing a cultural identity to Mongolia.

    About National Mission for Manuscripts

    • The Mission was launched in February 2003 under the Ministry of Tourism and Culture, with the mandate of documenting, conserving and disseminating the knowledge preserved in the manuscripts.
    • One of the objectives of the mission is to publish rare and unpublished manuscripts so that the knowledge enshrined in them is spread to researchers, scholars and the general public at large.
    • Under this scheme, reprinting of 108 volumes of Mongolian Kanjur has been taken up by the Mission.

  • Who was Herbert Kleber?

    With today’s doodle, Google is remembering Dr Herbert David Kleber, who reframed the field of addiction treatment.

    Try this question from CSP 2016:

    A recent movie titled The Man Who Knew Infinity is based on the biography of-

    (a) S. Ramanujan
    (b) S. Chandrasekhar
    (c) S. N. Bose
    (d) C. V. Raman

    Herbert Kleber

    • Born on June 19, 1934, in Pittsburgh, Pennsylvania, Dr Kleber studied medicine, where he discovered that psychology was his calling.
    • He viewed addiction as a medical condition rather than a moral failure.
    • He spent years treating people with drug addiction and realized that the treatment needed a new approach backed by scientific research.
    • His new methods of treatment gained an appreciation and he was appointed as the deputy director for demand reduction at the Office of National Drug Control Policy by the then U.S. President George H. W. Bush.
    • He headed many projects on developing new methods to treat individuals with alcohol, cocaine, heroin and alcohol addictions.

  • Lithium Nucleosynthesis in Stars

    A forty-year-old puzzle regarding the production of lithium in stars has been solved by Indian researchers.

    Try this question from CSP 2013:

    Q.Consider the following phenomena:

    1. Size of the sun at dusk
    2. Colour of the sun at dawn
    3. Moon being visible at dawn
    4. Twinkle of stars in the sky
    5. Polestar being visible in the sky

    Which of the above are optical illusions?

    (a) 1, 2 and 3

    (b) 3, 4 and 5

    (c) 1, 2 and 4

    (d) 2, 3 and 5

    Lithium nucleosynthesis in Stars

    • Stars, as per known mechanisms of evolution, actually destroy lithium as they evolve into red giants.
    • Planets were known to have more lithium than their stars — as is the case with the Earth-Sun pair.
    • However, leading to a contradiction, some stars were found that were lithium-rich.
    • The new work by an Indian researcher shows that when stars grow beyond their Red Giant stage into what is known as the Red Clump stage, they produce lithium.
    • This is known as a Helium Flash and this is what enriches them with lithium.

    Studying lithium-rich stars

    • About 40 years ago, a few large stars were spotted that were lithium-rich.
    • This was followed by further discoveries of lithium-rich stars, and that posed a puzzle — if stars do not produce lithium, how do some stars develop to become lithium-rich.
    • The planet engulfment theory was quite popular. For example, Earth-like planets may increase the star’s lithium content when they plunge into [their] star’s atmosphere when the latter become Red Giants.

    Findings of the Indian research

    • Indian researchers have been working on this puzzle for nearly 20 years to devise a method of measuring lithium content using low-resolution spectra in a large number of stars.
    • The study demonstrated that lithium abundance enhancement among low mass giant stars is common.
    • Until now, it was believed that only about 1% of giants are lithium-rich.
    • Secondly, the team has shown that as the star evolves beyond the Red Giant stage, and before it reaches the Red Clump stage, there is a helium flash which produces an abundance of lithium.

    Back2Basics: Lithium

    • Lithium is a chemical element with the symbol Li and atomic number 3. It is a soft, silvery-white alkali metal. Under standard conditions, it is the lightest metal and the lightest solid element.
    • S light element commonly used today in communication device technology, it has an interesting story.
    • It was first produced in the Big Bang, around 13.7 billion years ago when the universe came into being, along with other elements.
    • While the abundance of other elements grew millions of times, the present abundance of lithium in the universe is only four times the original [Big Bang] value. It is actually destroyed in the stars.
    • The Sun, for instance, has about a factor of 100 lower amount of lithium than the Earth.

  • Explaining Lithium increase in the Universe

    In a study recently published in Nature Astronomy scientists from Indian Institute of Astrophysics (IIA) along with their international collaborators have provided a robust observational evidence for the first time that Li production is common among low mass Sun-like stars during their He-core burning phase.

    Importance of lithium in our life

    • Light inflammable, metal lithium (Li) has brought about transformation in modern communication devices and transportation.
    • A great deal of today’s technology is powered by lithium in its various shades [remember Li-ion battery!].
    • But where does the element come from?
    • The origin of much of the Li can be traced to a single event, the Big-Bang that happened about 13.7 Billion years ago, from which the present-day Universe was also born.

    Why lithium was thought to be different?

    • Li content in the physical Universe has increased by about a factor of four over the life of the Universe.
    • However, the rest of the elements carbon, nitrogen, oxygen, iron, nickel and so on which grew about a million times over the lifetime of the Universe.
    • Li, however, understood to be an exemption!
    • Current understanding is that lithium in stars like our Sun only gets destroyed over their lifetime.
    • As a matter of fact, the composition of all the elements in the Sun and the Earth is similar.
    • But, the measured content of Li in the Sun is a factor of 100 lower than that of the Earth, though both are known to have formed together.

    So, what the new finding suggests?

    • This discovery challenges the long-held idea that stars only destroy lithium during their lifetime.
    • It implies that the Sun itself will manufacture lithium in the future.
    • This is not predicted by models, indicating that there is some physical process missing in stellar theory.
    • Further, the authors identified “He flash”.
    • “He flash” is an on-set of He-ignition at the star’s core via violent eruption at the end of the star’s core hydrogen-burning phase, as the source of Li production.
    • Our Sun will reach this phase in about 6-7 billion years.

  • Remembering P C Mahalanobis

    Prasanta Chandra Mahalanobis, India’s ‘Plan Man’ and the architect of the country’s statistical system is more relevant now in times of Covid pandemic when we grapple with the lack of data.

    Analysing 1944 Bengal famine

    • He conducted a large-scale sample survey of Bengal’s famine between July 1944 and February 1945.
    • Sample survey helped in causal analysis and to assess the extent of the disaster and an estimate of the number of people affected.

    Relevance today

    • Bengal’s famine survey reminds us that we need estimates of the millions who will lose jobs or livelihoods in today’s pandemic.
    • The extent of feasibility, success and problem of online access also needs to be properly estimated in this new dawn.
    • Mahalanobis is perhaps more relevant today when the accuracy of different sorts of data is under the scanner.
    • Mahalanobis envisaged large-scale sample surveys as statistical engineering rather than pure theory of sampling.
    • He was instrumental in establishing the National Sample Survey (NSS) in 1950 and the Central Statistical Organization in 1951.

    Data accuracy

    • Mahalanobis was very careful about data accuracy in his surveys.
    • In Kautilya’s Arthashastra, there is mention of the need for cross-checking by an independent set of agents for data collection.
    • This, according to Mahalanobis, was the “striking feature in the Arthashastra”.
    • This might have prompted him to have an independent supervisory staff during the conduct of field operations by the NSS.
    • His initial training in Physics might have made him conscious about errors in measurement and observation.
    • The desire to have built-in cross-checks and to get an estimate of errors in sampling led him to introduce the Inter-Penetrating Network of Subsamples.
    • The network is considered as the curtain-raiser for re-sampling procedures like Bootstrap.
    • Bootstrap is a revolutionary concept of statistics.

    Difficulties in conducting surveys

    • Even Mahalanobis could have faced hardship had he wished to conduct surveys now.
    • First, even in pre-COVID-19 India, it’s widely reported that surveyors were facing tremendous resistance from people due to some sociopolitical reasons.
    • Pronab Sen, Chairman of the Standing Committee on Economic Statistics, and former Chief Statistician, expressed his concern that the survey system is already in “deep trouble”.
    • Conducting household surveys with the Census as the frame would be “very tough” going ahead.
    • The problem will intensify due to COVID-19.

    Use of technology for survey

    • Mahalanobis never shied away from technology.
    • He was instrumental in bringing computers to India.
    • The Mahalanobis-led Indian Statistical Institute procured India’s first computer in 1956 and the second in 1959.

    Consider the question asked in 2019 “How was India benefitted from the contributions of Sir M.Visvesvaraya and Dr M. S. Swaminathan in the fields of water engineering and agricultural science respectively?”

    Conclusion

    Mahalanobis wrote: “Statistics are a minor detail, but they do help.” This is an eternal truth. What Mahalanobis didn’t spell out is that one needs a top statistician for listening to the heartbeats of data and for framing data-based policy decisions for human welfare and national development.

  • What is Raman Spectroscopy?

    Mumbai-based researchers have turned to Raman Spectroscopy to detect RNA viruses present in saliva samples.

    Try this question from CSP 2017
    Q.Which Indian astrophysicist and Nobel laureate predicted rapidly rotating stars emit polarized light?
    (a) Subrahmanyan Chandrasekhar
    (b) CV Raman
    (c) Ramanujan
    (d) Amartya Sen

    The Raman Spectroscopy

    • Raman spectroscopy is an analytical technique where scattered light is used to measure the vibrational energy modes of a sample.
    • In 1928, Raman discovered that when a stream of light passes through a liquid, a fraction of the light scattered by the liquid is of a different colour.
    • While Raman was returning from London in a 15-day voyage, he started thinking about the colour of the deep blue Mediterranean.
    • He wasn’t convinced by the explanation that the colour of the sea was blue due to the reflection of the sky.
    • As the ship docked in Bombay, he sent a letter to the editor of the journal Nature, in which he penned down his thoughts on this.
      Subsequently, Raman was able to show that the blue colour of the water was due to the scattering of the sunlight by water molecules.
    • By this time he was obsessed with the phenomenon of light scattering.

    How does it work?

    • The Raman Effect is when the change in the energy of the light is affected by the vibrations of the molecule or material under observation, leading to a change in its wavelength.
    • Significantly, it notes that the Raman effect is “very weak” — this is because when the object in question is small (smaller than a few nanometres), the light will pass through it undisturbed.
    • But a few times in a billion, light waves may interact with the particle. This could also explain why it was not discovered before.
    • In general, when light interacts with an object, it can either be reflected, refracted or transmitted.
    • One of the things that scientists look at when light is scattered is if the particle it interacts with is able to change its energy.

    Applications

    • Raman spectroscopy is used in many varied fields – in fact, any application where non-destructive, microscopic, chemical analysis and imaging is required.
    • Whether the goal is qualitative or quantitative data, Raman analysis can provide key information easily and quickly.
    • It can be used to rapidly characterize the chemical composition and structure of a sample, whether solid, liquid, gas, gel, slurry or powder.

  • What is Winter Diesel?

    India’s armed forces may soon be using winter diesel for operations in high altitude areas such as Ladakh, where winter temperatures plummet to extremely low as -30° Celsius.

    This year BS-VI compliant fuel was in news. Try differentiating the Winter Diesel with the BS-VI fuel.

    What is Winter Diesel?

    • Winter diesel is a specialised fuel that was introduced by Indian Oil Corp. Ltd. last year specifically for high altitude regions and low-temperature regions such as Ladakh, where ordinary diesel can become unusable.
    • The flow characteristics of regular diesel change at such low temperatures and using it may be detrimental to vehicles.
    • Winter diesel which contains additives to maintain lower viscosity can be used in temperatures as low as -30°C and that besides a low pour point, it had higher cetane rating — an indicator is the combustion speed of diesel and compression needed for ignition.
    • It has lower sulphur content, which would lead to lower deposits in engines and better performance.

    Back2Basics: BS-VI fuel

    • Sulphur content in fuel is a major cause for concern. Sulphur dioxide released by fuel burning is a major pollutant that affects health as well.
    • BS-VI fuel’s sulphur content is much lower than BS-IV fuel.
      It is reduced to 10 mg/kg max in BS-VI from 50 mg/kg under BS-IV.

    This reduction makes it possible to equip vehicles with better catalytic converters that capture pollutants. However, BS-VI fuel is expected to be costlier that BS-IV fuel.

    With inputs from:
    https://www.civilsdaily.com/news/pib-winter-grade-diesel/

  • Phobos: The closest and biggest moon of Mars

    The Mars Colour Camera (MCC) onboard ISRO’s Mars Orbiter Mission (MOM) has captured the image of Phobos, the closest and biggest moon of Mars.

    Try this question from CSP 2017:

    Q.Which region of Mars has a densely packed river deposit indicating this planet had water 3.5 billion years ago?

    (a) Aeolis Dorsa (b) Tharsis (c) Olympus Mons (d) Hellas

    About Phobos

    • Phobos is the innermost and larger of the two natural satellites of Mars, the other being Deimos.
    • Both moons were discovered in 1877 by American astronomer Asaph Hall.
    • Phobos is a small, irregularly shaped object with a mean radius of 11 km and is seven times as massive as the outer moon, Deimos.
    • Phobos is largely believed to be made up of carbonaceous chondrites.
    • The violent phase that Phobos has encountered is seen in the large section gouged out from a past collision (Stickney crater) and bouncing ejecta.

    Back2Basics: Mars Orbiter Mission (MOM)

    • The MOM also called Mangalyaan is a space probe orbiting Mars since 24 September 2014. It was launched on 5 November 2013 by the Indian Space Research Organisation (ISRO).
    • It aims at studying the Martian surface and mineral composition as well as scans its atmosphere for methane (an indicator of life on Mars).
    • It is India’s first interplanetary mission and it made it the fourth space agency to reach Mars, after Roscosmos, NASA, and the European Space Agency.
    • It made India the first Asian nation to reach Martian orbit and the first nation in the world to do so on its maiden attempt.
    • It was initially meant to last six months, but subsequently, ISRO had said it had enough fuel for it to last “many years.”

  • International Thermonuclear Experimental Reactor (ITER) Project

    The heavy engineering division of L&T dispatched a giant Cryostat lid, to International Thermonuclear Experimental Reactor (ITER) site in France from its Hazira unit in Gujarat.

    Try this MCQ:

    Q.With reference to International science projects, consider the following:

    1. Large Hadron Collider (LHC)– The God Particle
    2. Thirty Metre Telescope (TMT) – The World’s Most Advanced Telescope
    3. International-Thermonuclear-Experimental-Reactor (ITER) – Fusion Energy
    4. Facility for Antiproton and Ion Research (FAIR) – Antiproton and Ion Research

    Which of the above projects have India’s active participation?

    a) 1 only

    b) 2 and 3 only

    c) 1, 3 and 4 only

    d) All of them

    ITER Project

    • ITER is international nuclear fusion research and engineering megaproject, which will be the world’s largest magnetic confinement plasma physics experiment.
    • The goal of ITER is to demonstrate the scientific and technological feasibility of fusion energy for peaceful use.

    Minutes of the project

    • The project is funded and run by seven member entities—the European Union, India, Japan, China, Russia, South Korea and the United States.
    • The EU, as host party for the ITER complex, is contributing about 45 per cent of the cost, with the other six parties contributing approximately 9 per cent each.
    • Construction of the ITER Tokamak complex started in 2013 and the building costs were over US$14 billion by June 2015.

    How does it work?

    • ITER is the most complex science project in human history. The ITER aims to use a strong electric current to trap plasma inside a doughnut-shaped enclosure long enough for fusion to take place.
    • Hydrogen plasma will be heated to 150 million degrees Celsius, ten times hotter than the core of the Sun, to enable the fusion reaction.
    • The process happens in a doughnut-shaped reactor, called a tokamak 1, which is surrounded by giant magnets that confine and circulate the superheated, ionized plasma, away from the metal walls.
    • The superconducting magnets must be cooled to -269°C (-398°F), as cold as interstellar space.
    • Scientists have long sought to mimic the process of nuclear fusion that occurs inside the sun, arguing that it could provide an almost limitless source of cheap, safe and clean electricity.
    • Unlike in existing fission reactors, which split plutonium or uranium atoms, there’s no risk of an uncontrolled chain reaction with fusion and it doesn’t produce long-lived radioactive waste.

    Back2Basics: Nuclear Fusion

    • Nuclear fusion is the process of making a single heavy nucleus (part of an atom) from two lighter nuclei. This process is called a nuclear reaction.
    • The nucleus made by fusion is heavier than either of the starting nuclei. It releases a large amount of energy.
    • Fusion is what powers the sun. Atoms of Tritium and Deuterium (isotopes of hydrogen, Hydrogen-3 and Hydrogen-2, respectively) unite under extreme pressure and temperature to produce a neutron and a helium isotope.
    • Along with this, an enormous amount of energy is released, which is several times the amount produced by fission.
    • Scientists continue to work on controlling nuclear fusion in an effort to make a fusion reactor to produce electricity.

    How it is different from nuclear fission?

    • Simply put, fission is the division of one atom into two (by neutron bombardment), and fusion is the combination of two lighter atoms into a larger one (at a very high temperature).
    • Nuclear fission takes place when a large, somewhat unstable isotope (atoms with the same number of protons but a different number of neutrons) is bombarded by high-speed particles, usually neutrons.