Prelims Exam

Short Notes


Science and Tech.

1. ISRO’s Achievement in Minimizing Orbital Debris

Space Debris Explained

  • Inoperative man-made objects in Earth orbit.
  • Kessler Syndrome: Cascading collisions creating more debris, hindering space use.

International Agreements

  • Space Liability Convention (1972): Defines liability for damage from space objects.
  • No law against debris re-entering Earth’s atmosphere.

ISRO’s Mission

  • PSLV-C58/XPoSat mission (Jan 2024) left minimal debris.
  • Achieved by transforming the used stage into a stabilized platform (POEM-3).
  • POEM-3 deorbited for early re-entry into Earth’s atmosphere.


  • Minimizes orbital debris and potential collisions.
  • POEM-3 offers a cost-effective platform for space experiments.

Project NETRA

  • ISRO’s early warning system for detecting space hazards.
  • Aims to provide India with its own Space Situational Awareness (SSA) capability.
  • SSA helps predict threats to Indian satellites from space debris.



2. Angara Rocket (GS3/Science and Technology)

  • Russia successfully test-launched its Angara-A5 space rocket.
  • Features:
    • 3-stage rocket, 42.7 meters tall, weighing 773 tonnes.
    • Carrying capacity: 24.5 tonnes to space.
  • Purpose: Successor to Proton M as Russia’s heavy-lift rocket.
  • Background:
    • Developed after the Soviet Union’s collapse to ensure space access independent of Kazakhstan’s Baikonur Cosmodrome.
    • First test flight in 2014, followed by another in 2020 (both from Plesetsk, northern Russia).
    • Partial test failure in 2021.


3. Sustainable Hydrogel for Microplastics Removal

  • IISc researchers design a sustainable hydrogel to remove microplastics from water.
  • Features:
    • Unique intertwined polymer network for binding and degrading contaminants using UV light irradiation.
    • Three polymer layers (chitosan, polyvinyl alcohol, polyaniline) forming an interpenetrating polymer network (IPN).
    • Nanoclusters of copper substitute polyoxometalate (Cu-POM) for UV-light-induced degradation.
  • Efficiency: Removes about 95% and 93% of two different microplastics in near-neutral pH water.

Microplastics (Background)

  • Tiny plastic pieces less than 5 millimeters long, harmful to oceans and aquatic life.
  • Threat to human health – enter bodies through water, increasing illness risk.
  • Environmental hazard – found in remote areas like polar ice caps and deep ocean trenches, endangering ecosystems.


4. Water Rationing in Bogota

  • Bogota, Colombia’s capital city, implements water rationing due to scarcity.
  • Water Rationing: Limiting everyday water use during resource shortage.
  • Bogota:
    • Sprawling, high-altitude capital of Colombia.
    • Located on the Andean plateau known as Altiplano Cundiboyacense.



5. Whooping Cough 

  • Highly contagious respiratory illness (pertussis) caused by Bordetella pertussis bacteria.
  • Named for the “whooping” sound during coughing fits.
  • Particularly severe in infants, with complications like pneumonia and even death.
  • Spread: Through droplets from coughs or sneezes of infected people.
  • Symptoms: Begin with cold-like symptoms and low-grade fever. Progress to severe coughing with a “whooping” sound, leading to vomiting.
  • Vaccination: DTaP and Tdap vaccines protect children against whooping cough.



6. Volcanic Vortex Rings

Mount Etna erupting near-perfect rings of smoke called “volcanic vortex rings.”

  • Formation: Rapid gas (mainly water vapor) release through a circular vent in the crater.
  • Similar to smoke rings blown by humans.
  • First observed at Mount Etna and Vesuvius (Italy) in 1724.
  • Significance: Provides insights into volcanic activity and gas emissions (helps predict eruptions).

About Mount Etna

  • Active volcano on Sicily’s east coast (Mediterranean’s largest island).
  • Europe’s tallest volcano south of the Alps and one of the most active.
  • Five summit craters responsible for most eruptions.
  • Additional “flank” eruptions from vents on the mountain’s slopes.
  • Almost constant activity with over 60 flank eruptions and many more summit eruptions since 1600.
  • UNESCO World Heritage Site since 2013.



7. Corrupt Practices under Representation of the People Act, 1951 (RPA)

  • Section 123: Includes bribery, undue influence, false information, promotion of enmity/hatred for electoral gain.
  • Section 123(2): Undue influence – interferences with free exercise of electoral rights (threats, social ostracism, caste/community expulsion).
  • Section 100(1)(b): Election can be declared void if a returned candidate or their agent commits corrupt practices.
  • Sections 100(1)(d)(i) & (iv): Election results can be declared materially affected if there’s improper acceptance of nomination or non-compliance with relevant provisions.


8. Declaration of Movable Assets

  • Supreme Court judgement clarifies declaration of movable assets by election candidates.
  • Key takeaway: Not mandatory to declare every item (clothes, furniture, etc.) unless it’s a sizable asset or reflects lifestyle relevant to the candidacy.
  • Voters don’t have an absolute right to all details of a candidate’s private life.


Leave a Reply

Your email address will not be published. Required fields are marked *