Coronal Mass Ejections

• IAS NEXT, Lucknow
• 16, Mar 2022

Reference News:-

Indian researchers have developed a simple technique of separating the constant background of the Solar Corona and revealing the dynamic corona.

• The technique has been developed jointly by the Aryabhatta Research Institute and the Indian Institute of Astrophysics.

What is the technique? (NOT MUCH RELEVANT FROM THE EXAMINATION POINT OF VIEW).

The simple approach of subtracting the constant background can improve efficiency of identification of Coronal Mass Ejections (CME).

What are Coronal Mass Ejections (CMEs)?

Coronal Mass Ejections (CMEs) are large expulsions of plasma and magnetic field from the Sun’s corona.

• They can eject billions of tonnes of coronal material and carry an embedded magnetic field (frozen in flux) that is stronger than the background solar wind interplanetary magnetic field (IMF) strength.

Speed:

• CMEs travel outward from the Sun at speeds ranging from slower than 250 km per second (km/s) to as fast as near 3,000 km/s.
• The fastest Earth-directed CMEs can reach our planet in as little as 15-18 hours. Slower CMEs can take several days to arrive.
• They expand in size as they propagate away from the Sun, and larger CMEs can reach a size comprising nearly a quarter of the space between Earth and the Sun by the time it reaches our planet.

Impacts:

• They cause radio and magnetic disturbances on the Earth.
• They can drive the Space Weather in near-Earth space.