Electrically charged particles from space travelling at speeds of several hundred km/sec can severely harm living beings if they reach the surface of the Earth. What prevents them from reaching the surface of the Earth ?

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Q: 45 (IAS/2012)
Electrically charged particles from space travelling at speeds of several hundred km/sec can severely harm living beings if they reach the surface of the Earth. What prevents them from reaching the surface of the Earth ?

question_subject: 

Geography

question_exam: 

IAS

stats: 

0,145,93,145,48,17,28

keywords: 

{'outer space': [1, 0, 0, 1], 'particles': [1, 0, 5, 16], 'earth': [0, 1, 1, 1], 'ozone layer': [6, 0, 0, 6], 'magnetic field': [0, 0, 0, 6], 'atmosphere': [1, 1, 4, 7], 'space': [4, 1, 7, 12], 'beings': [1, 0, 0, 1], 'surface': [1, 0, 0, 0]}

The correct answer is: The Earth’s magnetic field diverts them towards its poles.

Explanation:

Electrically charged particles from space are also called cosmic rays. They are mainly composed of high-energy protons and atomic nuclei that travel through space at very high speeds.

When cosmic rays approach the Earth, they interact with the Earth`s magnetic field. The magnetic field deflects the charged particles, causing them to follow a curved path towards the poles. This is because the Earth`s magnetic field lines converge at the poles, and charged particles are guided towards these regions.

As the charged particles approach the Earth`s atmosphere near the poles, they collide with the atmospheric gases and produce a glowing display called the aurora borealis (northern lights) in the northern hemisphere and aurora australis (southern lights) in the southern hemisphere.

Therefore, the Earth`s magnetic field plays a crucial role in protecting the Earth from cosmic rays by diverting them towards the poles, where their energy is dissipated harmlessly in the upper atmosphere.