PANSPERMIA

TAG: GS 3: SCIENCE AND TECHNOLOGY

THE CONTEXT: The question of how life began has invited numerous hypotheses. One that has prevailed since ancient Greece is panspermia.

EXPLANATION:

Panspermia theory:

• Panspermia is a fringe theory that proposes the existence of life throughout the universe, distributed by space dust, meteoroids, asteroids, comets, and planetoids, as well as by spacecraft carrying unintended contamination by microorganisms.
• The theory suggests that life did not originate on Earth but was brought here by cosmic processes.
• Panspermia has been a topic of philosophical debate for millennia, but it remained speculative until recent decades.

Some key aspects of panspermia include:

• The panspermia theory suggests that life exists throughout the universe and can be distributed by space dust, meteoroids, asteroids, comets, and planetoids.
• However, the implications of panspermia for the origin of life are significant:
  • Alternative origin of life:
    • Panspermia proposes that life on Earth may have originated elsewhere in the universe, and its evolution on Earth is due to the delivery of life by cosmic processes
    • This challenges the widely accepted notion that life originated on Earth through natural processes.
  • Interplanetary and interstellar life transfer:
    • The theory implies that life could be transferred between planets, moons, and satellites, as well as between stars and galaxies.
    • This suggests that life might be more common in the universe than previously thought, as it would not be limited to Earth or a specific solar system.
  • Potential for life on other planets:
    • Panspermia raises the possibility that life could exist on other planets, such as Mars, Venus, or even extrasolar planets.
    • This encourages the search for life beyond Earth and provides a rationale for exploring other celestial bodies in the universe.
  • Common origin of life:
    • If panspermia is true, all life found throughout the solar system would have a common origin, as life would be distributed by cosmic processes rather than evolving independently on each planet.

Arguments against panspermia:

• Critics argue that panspermia does not answer the question of the origin of life and cannot be tested experimentally.
• Mainstream scientists generally do not support this theory due to its lack of validation and the enormous distance between stars, making interstellar panspermia an unlikely occurrence.
• However, the concept of panspermia continues to be explored, with some researchers working on mathematical treatments of how life might migrate naturally.

SOURCE: https://epaper.thehindu.com/reader