Why in News?
Scientists from ARIES (DST) and partner institutions have discovered that the Sun’s meridional plasma flow extends into the upper chromosphere, providing the first observational evidence supporting the “Magnetic Tree” hypothesis. The study was published in The Astrophysical Journal.
Key Highlights
- Meridional Flow: Slow movement of hot plasma from the Sun’s equator toward the poles, acting as a conveyor belt for magnetic fields and regulating the 11 year solar cycle.
- Major Discovery: The poleward plasma flow continues up to 3,000 km above the Sun’s visible surface (upper chromosphere), linking the Sun’s surface with its upper atmosphere.
- Magnetic Tree Hypothesis: Magnetic structures in the upper atmosphere remain connected to deeper layers, similar to branches connected to a tree’s trunk and roots.
- Technique Used: Researchers analysed 27 years of radio observations from Japan’s Nobeyama Radioheliograph using a novel image correlation technique.
- Flow Speed: Plasma moves toward the poles at 5 to 15 m/s, comparable to speeds in the Sun’s lower layers.
- Solar Cycle Link: Flow patterns vary with the Sun’s 11 year solar cycle and differ between hemispheres depending on magnetic activity.
- Space Weather Significance: Improves understanding of the solar dynamo, solar storms, and space weather affecting satellites, GPS, communication systems, and power grids.
Key Terms
- Chromosphere: Layer of the Sun’s atmosphere located above the photosphere and below the corona.
- Solar Dynamo: Process by which plasma motion generates the Sun’s magnetic field.
- Space Weather: Conditions caused by solar activity that influence Earth’s technological systems.
[2022] If a major solar storm (solar flare) reaches the Earth, which of the following are the possible effects on the Earth?:
1. GPS and navigation systems could fail.
2. Tsunamis could occur at equatorial regions.
3. Power grids could be damaged.
4. Intense auroras could occur over much of the Earth.
5. Forest fires could take place over much of the planet.
6. Orbits of the satellites could be disturbed
7. Shortwave radio communication of the aircraft flying over polar regions could be interrupted.
Select the correct answer using the code given below;
[A] 1, 2, 4 and 5 only
[B] 2, 3, 5, 6 and 7 only
[C] 1, 3, 4, 6 and 7 only
[D] 1, 2, 3, 4, 5, 6 and