VOYAGER MISSION

• In 1972, NASA cancelled its plans of exploring the five outer planets (Mars, Jupiter, Saturn, Uranus and Neptune) with four highly complex spacecraft  the proposal, estimated to cost $ 1 billion, was scrapped due to budgetary constraints
• Instead, it proposed to send the Voyager probes, initially slated to explore only Jupiter and Saturn
• In 1974, however, it was decided that if one spacecraft completes the mission, the other one would be redirected towards Uranus and then Neptune
• Interestingly, the spacecraft were scheduled for a take-off towards the end of the 1970s for a reason
• According to a report by Scientific American, NASA chose the particular launch window to take advantage of a rare alignment of Jupiter, Saturn, Uranus and Neptune that occurs once every 175 years

• The alignment allowed the spacecraft to harness the gravity of each planet and swing from one to the next using relatively minimal amounts of fuel.
• NASA first demonstrated the technique with its Mariner 10 mission to Venus and Mercury from 1973 to 1975
• Voyager 2 was launched on August 20, 1977, two weeks before the September 5 Voyager 1 takeoff.
• This reversal of order took place as the two spacecraft were put on different trajectories  Voyager 1 was set on a path to reach Jupiter and Saturn, ahead of Voyager 2

• Voyager 1 and Voyager 2 are identical spacecraft. Each of them is equipped with instruments to carry out 10 different experiments
• The instruments include television cameras  to take images of planets and other celestial bodies infrared and ultraviolet sensors, magnetometers, plasma detectors, and cosmic-ray and charged-particle sensors.

• Both spacecraft feature a large antenna, 3.7 metres in diameter, which is used to receive commands from Earth and radio their findings back to the planet
• As their mission involved going far away from the Sun, they aren’t powered by solar power, like other spacecraft are
• Instead, Voyager relies on a small nuclear power plant, drawing hundreds of watts from the radioactive decay of a pellet of plutonium
• Notably, each Voyager spacecraft is adorned with a golden phonograph record  a 12-inch disc, intended to be a sort of time capsule from Earth to any extraterrestrial life that might intercept the probes in the distant future

• Fifteen months after its launch, Voyager 1 reached its first target planet, Jupiter, on March 5, 1979, and was soon followed by Voyager 2, which arrived there on July 9
• The most interesting discoveries made by Voyager 1 included the finding that Io, one of Jupiter’s moons, was geologically active
• The spacecraft noted the presence of at least eight active volcanoes “spewing material into space, making it one of the most (if not the most) geologically active planetary bodies in the solar system,”
• Moreover, Voyager 1 and Voyager 2 discovered three new moons of Jupiter: Thebe, Metis and Adrastea
• Following the Jupiter encounter, the spacecraft, one by one, moved towards Saturn. While passing by the planet’s moon Titan, Voyager 1 discovered that it wasn’t the biggest moon of our solar system, contrary to what scientists of the time believed — “the diameter of the solid centre was found (through radio signals) to be smaller than Jupiter’s Ganymede”

• After the Saturn expedition, as Voyager 1 headed on a trajectory to escape the solar system, Voyager 2 was redirected towards Uranus — both probes had fulfilled their primary mission goals but scientists kept them operational for further exploration

• Voyager 2 arrived at Uranus in 1986, becoming the first human-made object to fly past the aquamarine planet.
• The spacecraft took stunning photographs and confirmed that the main constituents of Uranus are hydrogen and helium.
• It also discovered 10 new moons and two new rings in addition to the previously-known nine rings, among other significant findings

• Then, the probe went to Neptune. Becoming the first human-made object to fly by the planet in 1989, Voyager 2 made some more notable discoveries there
• Apart from finding new moons and rings, it discovered that Neptune is more active than previously thought  winds on the planet blow at the speed of 1,100 kph. 
• after the Neptune encounter, Voyager 2, like Voyager 1, was put on the path to head out of the solar system.
• While Voyager 1 officially entered interstellar space in August 2012, Voyager 2 made its entry in November 2018

STUDY ON CLIMATE CHANGE

 

1. Context

The colour of the Earth’s oceans has significantly altered over the past two decades, most likely due to human-induced climate change, according to a new study. Over 56 per cent of the oceans, more than the total land area on the planet, have experienced a shift in colour.

2. Introduction

• A recent study titled 'Global climate-change trends detected in indicators of ocean ecology' published in Nature has shed light on the changing colours of the oceans and its potential impact on marine ecosystems.
• Conducted by a team of researchers from the United Kingdom-based National Oceanography Centre and various universities in the USA, the study examines the reasons behind the colour changes and their possible implications for ocean life and human societies.

3. Understanding Ocean Colour

• The colour of most oceans appears blue or navy blue due to the absorption and scattering of light. Longer-wavelength colours like red, yellow, and green are absorbed by the water molecules, while blue and violet, with shorter wavelengths, are reflected back, resulting in the characteristic blue appearance.
• However, the colour of an ocean may vary depending on factors such as water depth, cleanliness, and the presence of phytoplankton.

Image Source: The Indian Express

4. Role of Phytoplankton

• In regions with high concentrations of phytoplankton, the ocean appears greenish.
• Phytoplankton, microscopic marine algae, contain chlorophyll, a green-coloured pigment that helps them absorb sunlight.
• Through photosynthesis, phytoplankton convert carbon dioxide into sugars and release oxygen.
• The presence and density of phytoplankton influence the shades of blue-green or green observed in specific ocean regions.

Image Source: The Indian Express

5. The Study Methodology

• To conduct the study, the researchers analyzed data from NASA's Aqua satellite, monitoring ocean colour since 2002.
• The examination of two decades of data revealed that over 50% of the world's oceans experienced a change in colour.
• To ascertain the link between these changes and climate change, a climate model was used to simulate the planet's oceans under different scenarios, including greenhouse gas additions.
• The results showed a significant trend within 20 years, corroborating the real-world satellite data analysis.

6. Reasons Behind Ocean Colour Changes

• The study indicates that tropical ocean regions near the equator are most affected, with the water shifting from blue to green. However, the changes are complex and varied in different locations.
• The research points towards increased ocean stratification due to climate change.
• Ocean stratification results from the separation of water layers by density, impacting ecosystems, carbon absorption, and nutrient distribution.
• The reduced nutrient supply favours smaller plankton, causing changes in plankton communities, which manifest as changes in ocean colour.

7. Implications for Marine Ecology

• Changes in plankton population composition have far-reaching effects on marine ecosystems.
• Plankton, including phytoplankton and zooplankton, play a vital role in supporting marine food webs.
• Any alteration in their populations could disrupt the delicate balance of the marine ecosystems, affecting marine life forms crabs and fish to sea stars.
• Additionally, the ability of the ocean to absorb carbon dioxide is impacted by the types od plankton present.

8. Conclusion

• The study highlights the significance of ocean colour changes as a potential indicator of shifting marine ecosystems.
• As climate change leads to increased ocean stratification and altered plankton communities, the implications for marine life and carbon absorption become critical concerns.
• Understanding these changes can help to inform necessary actions to protect marine biodiversity and ensure a sustainable future for both ocean life and human societies.

For Prelims: Climate Change, National Oceanography Centre, Global Climate Change, Marine ecology, Phytoplankton, Zooplankton, Chlorophyll, and NASA. For Mains: 1. Examine the factors responsible for the different colours observed in oceans across the world. How does the presence of phytoplankton influence the appearance of the Ocean? (250 words).

 

Previous year Questions 1. Consider the following factors: (UPSC 2012) 1. Rotation of the Earth 2. Air pressure and wind 3. Density of ocean water 4. Revolution of the Earth Which of the above factors influences the ocean currents? A. 1 and 2 only B. 1, 2 and 3 C. 1 and 4 D. 2, 3 and 4 Answer: B   2. With reference to Ocean Mean Temperature (OMT), which of the following statements is/are correct? (UPSC 2020) 1. OMT is measured up to a depth of 26°C isotherm which is 129 meters in the south-western Indian Ocean during January-March. 2. OMT collected during January-March can be used in assessing whether the amount of rainfall in monsoon will be less or more than a certain long-term mean. 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 Answer: B   3. Tides occur in the oceans and seas due to which among the following? (UPSC 2015) 1. Gravitational force of the Sun. 2. Gravitational force of the Moon 3. Centrifugal force of the Earth Select the correct answer using the code given below. A. 1 only B. 2 and 3 only C. 1 and 3 only D. 1, 2 and 3 Answer: D   4. The acidification of oceans is increasing. Why is this phenomenon a cause of concern? (UPSC 2012) 1. The growth and survival of calcareous phytoplankton will be adversely affected. 2. The growth and survival of coral reefs will be adversely affected. 3. The survival of some animals that have phytoplanktonic larvae will be adversely affected. 4. The cloud seeding and formation of clouds will be adversely affected. Which of the statements given above is/are correct? A. 1, 2 and 3 only B. 2 only C. 1 and 3 only D. 1, 2, 3 and 4 Answer: A   5. Consider the following statements: (UPSC 2018) 1. Most of the world's coral reefs are in tropical waters. 2. More than one-third of the world's coral reefs are located in territories of Australia, Indonesia and the Philippines. 3. Coral reefs host far more number of animal phyla than those hosted by tropical rainforests. Which of the statements given above is/are correct? A. 1 and 2 only B. 3 only C. 1 and 3 only D. 1, 2 and 3 Answer: D   6. With reference to the 'Indian Ocean Dipole (IOD)' sometimes mentioned in the news while forecasting the Indian monsoon which of the following statements is/are correct? (UPSC 2017) 1. IOD phenomenon is characterised by a difference in sea surface temperature between the tropical Western Indian Ocean and the tropical Eastern Pacific Ocean. 2. An IOD phenomenon can influence an EI Nino's impact on the monsoon. 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 Answer: B

Source: The Indian Express

PRIVILEGE MOTION

 

 

1. Context

Rajya Sabha Chairman Jagdeep Dhankhar referred complaints related to the privilege of the House against TMC’s Derek O’Brien and AAP’s Raghav Chadha to the privileges committee on Thursday (August 3 2023)

 

2. What is Privilege motion?

• A privilege motion is a motion that can be moved in the Indian Parliament by a member if they believe that their privileges or the privileges of the House have been violated. Privileges are certain rights and immunities that are granted to members of Parliament so that they can effectively discharge their functions
• The rules governing privilege motions are set out in the Rules of Procedure of the Lok Sabha and the Rajya Sabha. A privilege motion must be moved in writing and must be signed by the member who is moving it. The motion must be specific and must set out the details of the alleged breach of privilege
• Once a privilege motion has been moved, it is referred to the Privileges Committee of the House.
• The Privileges Committee is a standing committee of the House that is responsible for investigating allegations of breach of privilege.
• The Committee has the power to summon witnesses, take evidence, and make recommendations to the House
• If there is a belief that such a privilege has been breached, a motion can be raised by any member.
• It can be admitted by the Chairman. They can then refer it to the Privileges Committee. The Chairman can, from time to time, nominate such a Committee, consisting of ten members.
• It will also have a Chairman appointed by the Rajya Sabha Chairman

The right to raise a question of privilege is based on satisfying two conditions, namely:

(i) the question shall be restricted to a specific matter of recent occurrence, and

(ii) the matter requires the intervention of the Council

 

• Similar provisions exist in Lok Sabha with the Speaker having the power to make such decisions.
• The Speaker/RS chairperson is the first level of scrutiny of a privilege motion. Therefore, the Speaker/Chair can decide on the privilege motion himself or herself or refer it to the privileges committee of Parliament

3.Actions by Previleges can take

• The mandate of the committee is to examine such cases and “make such recommendations as it may deem fit”
•  It can call the relevant people as part of its examination and look at related documents.
•  It has to then make a report and if the Council has not fixed any time for its presentation, the report shall be presented within one month of the date on which reference to the Committee was made
• A motion has to be passed for the consideration of the report and amendments can be suggested
• The Chairman or any member of the Committee or any other member can move that the Council agrees, disagrees, or agrees with amendments, with the recommendations contained in the report

4. Previous Instances

• A large number of notices are rejected, with penal action recommended in only a few cases
• The most significant case was in 1978 when Indira Gandhi, who had just won the Lok Sabha elections from Chikmaglur, was expelled from the House
• Home minister Charan Singh moved a resolution of breach of privilege against her following observations made by the Justice Shah Commission, which probed excesses during the Emergency
• Another case was the expulsion of Subramanian Swamy from the Rajya Sabha in 1976
• Swamy was charged with bringing disrepute to Parliament through his activities through interviews in foreign publications that were construed as “anti-India propaganda”

 

For Prelims: No Confidence Motion, Privilege motion For Mains: 1.Standing committees play a crucial role in scrutinizing the government's financial proposals. Explain the role of these committees in the budgetary process and their role in ensuring fiscal prudence and accountability 2.Critically assess the challenges faced by standing committees in discharging their duties effectively. Suggest measures to strengthen the role of these committees in parliamentary proceedings

 

 

Source: indianexpress

NUCLEAR BOMB

1. Context

Recently, President Vladimir Putin's alarming statements to the G7's call for a nuclear-free world, the gravity of these weapons cannot be underestimated. In light of the recent movie "Oppenheimer", which delves into the ethical dilemmas surrounding their creation, it is essential to understand the science behind nuclear bombs and the profound consequences they carry.

2. About Atoms and Nuclear Fission

• To comprehend nuclear weapons, we must first understand the fundamental building blocks of matter: atoms.
• Atoms consist of protons, neutrons, and electrons, with the nucleus containing protons and neutrons at its core.
• Unstable atoms, known as radioactive isotopes, can undergo nuclear fission, breaking into two lighter elements and releasing atomic energy.
• Uranium-235, a rare isotope of uranium is the most common fuel for nuclear fission due to its ability to quickly undergo induced fission.

3. Enriching Uranium

• Practical implementation of nuclear weapons requires overcoming several challenges.
• Natural uranium, comprising mostly non-fissionable U-238, must be enriched to increase the concentration of U-235. 
• This enrichment process is carried out in specialized facilities, demands complex equipment and poses a significant non-proliferation challenge.

Image Source: Wikipedia

4. Triggering the Chain Reaction

• Engineers face the task of ensuring that a nuclear bomb is not triggered prematurely, preventing accidental explosions.
• Fission bombs utilize two primary trigger mechanisms: gun-type and implosion devices.
• The former involves shooting one subcritical mass into another to form a supercritical mass and initiate the chain reaction.
• The latter, used for plutonium bombs, compresses subcritical masses together to achieve critical mass and initiate the explosion.

5. Fusion Bombs

• While fission bombs are highly destructive, fusion bombs, also known as hydrogen bombs or H-bombs, are far more powerful.
• Fusion involves combining the nuclei of hydrogen isotopes, deuterium and tritium, releasing immense energy.
• Fusion bombs are complex, requiring a fission bomb to generate the necessary heat and pressure for fusion to occur.

6. The impact of Nuclear Explosions

Nuclear explosions release four types of energy

1. A blast wave capable of devastating physical structures,
2. Intense heat causes instant destruction,
3. Bright light leads to permanent blindness at considerable distances and
4. Deadly radiation is emitted immediately and over time.

7. The Way Forward

• The science behind nuclear weapons is based on harnessing the energy released through nuclear fission and fusion reactions.
• As discussions on their potential use and disarmament continue, it is vital to comprehend the destructive power they possess and the ethical challenges they raise.
• A world free from nuclear weapons remains an aspirational goal, emphasizing the need for diplomatic efforts and international cooperation to address this critical global issue.

 

For Prelims: Nuclear Bomb, G7, Hydrogen bombs, Uranium,  For Mains:  1. Discuss the ethical considerations associated with nuclear weaponry and the role of international cooperation in achieving a nuclear-free world. (250 Words)

 

 

Previous Year Questions 1. What is/are the consequence/consequences of a country becoming a member of the 'Nuclear Suppliers Group'? (UPSC 2018) 1. It will have access to the latest and most efficient nuclear technologies. 2. It automatically becomes a member of "The Treaty on the Non-proliferation of Nuclear Weapons (NPT)". Which of the statements given above is/are correct? A. 1 only              B. 2 only                C. Both 1 and 2              D. Neither 1 nor 2   Answer: A   2. In which one of the following groups are all the four countries members of G20? (UPSC 2020)  A. Argentina, Mexico, South Africa and Turkey B. Australia, Canada, Malaysia and New Zealand C. Brazil, Iran, Saudi Arabia and Vietnam D. Indonesia, Japan, Singapore and South Korea   Answer: A   3. Hydrogen bomb is based on the principle of (67th BPSC Prelims 2022) (Chhattisgarh Police SI Prelims 2012) A. controlled fusion reaction B. uncontrolled fusion reaction C. controlled fission reaction D. uncontrolled fission reaction D. None of the above/More than one of the above   Answer: B   4. To meet its rapidly growing energy demand, some opine that India should pursue research and development on thorium as the future fuel of nuclear energy. In this context, what advantage does thorium hold over uranium? (UPSC 2012) 1. Thorium is far more abundant in nature than uranium. 2. On the basis of per unit mass of mined mineral, thorium can generate more energy compared to natural uranium. 3. Thorium produces less harmful waste compared to uranium. Which of the statements given above is/are correct? A. 1 only         B. 2 and 3 only        C. 1 and 3 only          D.  1, 2 and 3   Answer: D   5. In India, why are some nuclear reactors kept under "IAEA Safeguards" while others are not? (UPSC 2020)  A. Some use uranium and others use thorium B. Some use imported uranium and others use domestic supplies C. Some are operated by foreign enterprises and others are operated by domestic enterprises D. Some are State-owned and others are privately-owned   Answer: B

 

Source: The Indian Express

INDIAN EAGLE OWL

 

1. Context

The Indian eagle-owl, identified as a separate species from its Eurasian counterpart, stands as an awe-inspiring bird with its imposing presence and unique characteristics.

2. Indian Eagle Owl

• The Indian eagle owl, scientifically known as Bubo bengalensis, is a magnificent and imposing bird of prey native to the Indian subcontinent.
• It belongs to the owl family (Strigidae) and is a distinct species from its Eurasian counterpart.
• With its striking appearance and fascinating behaviors, the Indian eagle owl has captivated the attention of bird enthusiasts and researchers alike.

Image Source: The Hindu

3. Physical Attributes

• The Indian eagle owl, particularly the slightly larger female, boasts an impressive size, reaching up to two and a half feet in length with a six-foot wingspan.
• Its most striking feature is the prominent ear tufts resembling horns, which may serve as a defensive mechanism against predators, exuding an aura of menace.

4. Nocturnal Habits and Elusiveness

• Due to its nocturnal habits, the Indian eagle-owl remains largely veiled in mystery, as very little is known about its behavior and population.
• Its adaptive nature allows it to thrive in open scrublands and agricultural areas, making it a widespread bird across the entire Indian peninsula.
• However, the secretive nature of its nighttime activities adds to its elusive reputation.

5. Habitat and Nesting

• The Indian eagle owl exhibits a preference for mango trees near human settlements.
• Its nesting sites often consist of scratched-out hollows, sometimes making it vulnerable to intrusions by predators or humans.
• When threatened, this owl displays ferocious defensive behavior, swooping down on intruders and striking with its talons.

6. Myths and Superstitions

• Near human habitations, the Indian eagle owl has become entangled in superstitions and folklore.
• In many rural regions of India, it is considered a bearer of ill omens, with its loud double-hoot calls believed to foretell the future.
• These myths resonate with similar beliefs found in various cultures around the world, attributing owls with both ominous and wise connotations.

7. Beneficial for Farmers

• Despite superstitions, the Indian eagle owl plays a valuable role in agriculture.
• Research has shown that owl nesting near agricultural lands leads to more and healthier owlets, thanks to the abundance of rodents in the vicinity.
• As natural predators, these owls contribute to pest control and support farmers' efforts.

8. A Call for Attention

• While India witnesses a surge in birding and conservation efforts, nocturnal birds like the Indian eagle owl are often overlooked during daytime activities.
• Birdwatchers and enthusiasts focus mainly on diurnal species, leaving the owl's nighttime behaviors and habits understudied.
• Raising awareness about this enigmatic bird will encourage further research and appreciation for its significance in India's avian ecosystem.

9. Conclusion

• The Indian eagle-owl stands as a remarkable and distinct species, capturing the imagination with its imposing presence and mysterious nocturnal habits.
• As we unravel the secrets of this elusive creature, fostering understanding and conservation efforts will ensure that this magnificent bird continues to thrive across the Indian landscape.

For Prelims: Indian Eagle Owl, Bubo bengalensis, Indian Subcontinent.

Source: The Hindu