7 Theories of Origin of Earth – Part – 2 YouTube Lecture Handouts
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Origin of Earth
- 4.6 billion years ago
- Sun and planets coalesced out of a vast cloud of gas and dust.
- Earth was hot glowing ball of white hot gases.
- Particles of gases were compressed together, giving off heat.
- Gases cooled down.
- Heavy material went to center of earth.
- Liquid material went to center.
Otto Schmidt՚s Inter-Stellar Dust Cloud Hypothesis
- Otto Schmidt: A Russian scientist.
- He proposed his ‘Inter- stellar – dust’ hypothesis in 1943.
- To explain the complex problem of the origin of the earth and the solar system.
Nova Hypothesis - Hoyle & Lyttleton
- Nova Hypothesis: The sun had another companion star which was much bigger than the sun, and the two together constituted a binary system.
- Hoyle and Lyttleton: The planets of the solar system have an originated from the expanding gases obtained from the explosion of a supernova.
Binary Star Hypothesis – Russell
- Propounded in 1937.
- To remove the shortcomings of tidal hypothesis of sir James Jeans.
Big Bang Theory
STEADY STATE THEORY
- It is an alternative to the Big Bang model of the evolution of the universe.
Electromagnetic Theory - Hannas Alfven
- Hannas Alfven was a Swedish scientist.
- Considered one of the founding father of the field of space plasma physics.
- He Known for:
- Magnetohydrodynamics
- Plasma cosmology
- Alfvén wave
Dust Gas Cloud Theory – Weizsacker
- This hypothesis explains well some of the observed phenomena relating to solar system.
✍ Manishika