Prelim Bits 17-11-2023 | UPSC Daily Current Affairs

Disappearance of Saturn’s Rings

Recently, scientists revealed that in 2025, Saturn will align edge-on with Earth, rendering its splendid rings virtually invisible.

Saturn is the 6th planet from the Sun, 2nd largest in the solar system after Jupiter and a gas giant composed primarily of hydrogen and helium. It has radius about 9 times that of Earth, although it has a low density and is only about 95 times more massive than Earth.

• Saturn’s Rings – It is primarily ice particles with a smaller fraction of rocky debris and dust ranging from micrometres to meters in size that spreads out over 280,000km from the planet.
• 7 distinct rings are named as A, B, C, D, E, F, and G rings with varying transparency and brightness.

In 1610, Galileo Galilei, renowned as the pioneer of modern astronomy, 1st laid eyes upon the magnificent rings of Saturn.

• Origin – May be from remnants of comets, asteroids, and moons which were ripped apart by the planet’s immense gravitational pull.
• It is younger than a tenth of Saturn’s own age.
• Rings orbit – Directly above Saturn’s equator and so they are tilted to the plane of Saturn’s orbit.

While Earth’s equator is tilted by 23.5 degrees, Saturn’s equator has a 26.7 degree tilt and so just like Earth, Saturn experiences seasons, but more than 29 times longer than ours.

• Disappearance – As Saturn tilts, its rings will seem to vanish due to the planet’s tilt and Earth’s perspective.
• As the seasons on Saturn progress, the southern side of the rings tilted Earth’s way to the northern side and then, the planet tips back to reveal the southern side once more.
• When it is edge-on, the rings appear to vanish seen from a distance as they are so thin.
• Twice per Saturnian year (29.4 Earth Year), we see the rings edge on and they all but vanish from Earth’s view point.

The last time Saturn’s rings seem to be invisible was in 2009 and it gradually became visible again. Now, the rings will be edge on once again in March 2025 and they’ll gradually come back into view, before sliding out of view again in November 2025.

Reference

1. The Hindu| Saturn’s Rings Disappear
2. Earth| Saturn’s Rings

Working of Electric Battery

Electric battery, as a portable sources of electric power are at the foundation of convenience and sustainability.

• Electric cell – A device that converts chemical energy into electrical energy.

• Principle – It uses redox reactions to produce an electric current which is combination of both oxidation (release of electrons) and reduction (consumption of electrons) reaction.
• Working – A voltaic, or galvanic cell consists of 2 half-cells where each half-cell is made of a metal electrode immersed in an electrolyte of that metal.
  • For example, a zinc electrode in zinc sulphate and a copper electrode in copper sulphate.
• The zinc oxidises at the anode, releases 2 electrons into the electrode and Zn2+ ions goes into the electrolyte.
• Copper ions (Cu2+) from the copper sulphate deposit onto the cathode, which now requires 2 electrons thus copper reduces at the cathode.
• So, the wire connecting the electrodes transports 2 electrons from anode to cathode.
• An external circuit connected to the wire can draw the electron flow for various applications.

An electric battery is a combination of electric cells.

Reference

The Hindu| Working of Electric Battery

Smog Tower

Recent research by IIT-Bombay found that smog tower at Connaught Place, New Delhi cleans air with 50% efficiency that drops to 30% at a distance of 50 meters from the filters, and just above 10% when 500 meters away.

• Working – Polluted air is sucked in and made to pass through 1000’s of filters to remove dust particles and then clean air is released back to the atmosphere.
• Updraft air cleaning system – It sucks in polluted air from bottom sends it upwards to the filters and clean air is distributed.
• Downdraft air cleaning system – It sucks in polluted air from above, sends it down to the filters, and clean air is then distributed.

• Inward fans – When operated, they create a negative pressure that helps to suck the polluted air from outside into the tower.
• Filters – It have both macro and micro layers to trap particles of 10 microns and larger, and particles of around 0.3 microns, respectively.
• Outward fans – They are kept in different directions in the outward vent and when operated, the filtered air is released (at a rate of 1,000 cubic metres per second in Connaught Place tower).
• Challenges – Higher installation cost and requirement of lot of maintenances.
• As they operate outdoors, it cannot clean enough air or fast enough.
• As soon as filtered air is released, it mixes again with the surrounding pollution, which offsets any improvements.

Reference

The Economic Times| Working of Smog Tower

Worldwide Governance Indicators (WGI)

Recently, Chief Economic Adviser of India stressed on the need for the World Governance Index to be more transparent and less subjective as it has been used for ratings assessment by credit ratings agencies.

The WGI is developed in 1999 by 2 World Bank researchers and the data will be updated annually every September.

• It is released by the World Bank (WB).
• Objective - To help researchers and analysts assess broad patterns in perceptions of governance across countries and over time.
• It provide a ranking of 215 countries territories.
• Criteria – It is based on 6 dimensions of governance

• Data Source – It aggregate data from more than 30 think tanks, international organizations, NGOs, and private firms across the world selected on the basis of 3 key criteria
  • They are produced by credible organizations.
  • They provide comparable cross-country data.
  • They are regularly updated.
• Issues – Data’s are based on subjective opinions of some institutions which might be erroneous or manipulated.

Credit rating – It is an assessment of the creditworthiness of a borrower (individual, corporation, state or provincial authority, or sovereign government) in general terms or with respect to a particular debt or financial obligation.

Credit rating agency (CRA) - It is a company that assigns credit ratings and there are 6 credit rating agencies registered under SEBI namely, CRISIL, ICRA, CARE, SMERA, Fitch India and Brickwork Ratings.

References

1. Indian Express| Issues with Worldwide Governance Index
2. World Bank| Worldwide Governance Indicators (WGI)

International Monetary Fund (IMF) Quota

International Monetary Fund (IMF) executive board approves 50% quota increase to strengthen resources following the guidance from the International Monetary and Financial Committee (IMFC) at the 2023 annual meetings.

• Quotas are the building blocks of the IMF’s financial and governance structure which are denominated in Special Drawing Rights (SDRs), the IMF’s unit of account.
• Reflection – An individual member country’s quota broadly reflects its relative position in the world economy.
• Usage of IMF Quotas

Currently, India has a quota of special drawing rights (SDR) 13,114.4 million which denotes a share of 2.75%, making it the 8^th largest quota-holding country in the IMF. Based on the quota, India has 132,063 votes, which denotes a share of 2.63%.

• Quota revival – The IMF’s board of governors conducts general reviews at least every 5 years.

Any changes in IMF quotas require approval by 85% of the total voting power, and a member’s own quota cannot be changed without its consent.

• Significance of quota increase – It would enhance the IMF’s permanent resources and strengthen the quota-based nature of the fund by reducing the reliance on borrowing.
• It would safeguard global financial stability and respond to members’ potential needs in an uncertain and shock-prone world.

Reference

1. Business Standard| IMF Quota increase
2. IMF| IMF Quotas