Early Warning Signs Before Solar Flare Eruptions (Geography)
Early Warning Signs Before Solar Flare Eruptions (Geography)
Why In News:
A recent scientific study of the Aditya-L1 mission has identified measurable precursor signals in the Sun's atmosphere that appear shortly before some solar flares, creating a potential early-warning window for space-weather forecasting.
Key Findings of the Study
Precursor Brightenings: Researchers noticed tiny, transient bursts of energy in the solar chromosphere hours before larger eruptions.
Spatial Clustering: These precursor signals clustered directly around the specific active regions where major flares later developed.
Magnetic Destabilization: Scientists believe these small-scale energy releases progressively weaken the local magnetic field, triggering the bigger flare.
Solar Flares
A solar flare is a sudden and intense release of electromagnetic radiation caused by the rapid release of magnetic energy in active regions of the Sun.
Solar flares commonly originate near sunspots, where strong and complex magnetic fields are present.
Flares are classified as A, B, C, M and X, in increasing order of intensity, with X-class being the strongest.
Coronal Mass Ejections
A Coronal Mass Ejection (CME) is a large-scale expulsion of magnetised plasma from the Sun's corona.
A solar flare and CME are related but distinct phenomena; they may occur together but one does not necessarily imply the other.
When directed towards Earth, a CME can interact with Earth's magnetic field and trigger a geomagnetic storm.
Solar Cycle
Solar activity varies through an approximately 11-year solar cycle, during which the number of sunspots and solar eruptions changes.
Solar maximum represents the period of relatively high solar activity and increased occurrence of solar flares and CMEs.
The present cycle is Solar Cycle 25.
India's Solar Observation and Space-Weather Efforts
a) Aditya-L1
Aditya-L1 is India's first dedicated space-based solar mission, launched by ISRO in 2023.
It is positioned around the Sun–Earth L1 Lagrange point, enabling continuous observation of the Sun with minimal interruption by Earth.
Its payloads include the Visible Emission Line Coronagraph (VELC) for studying the solar corona and Solar Ultraviolet Imaging Telescope (SUIT) for observing the Sun in ultraviolet wavelengths.
b) Indian Institutions
The Indian Institute of Astrophysics (IIA) is involved in research on the Sun, solar atmosphere and related astrophysical phenomena.
The Physical Research Laboratory (PRL) undertakes research in areas including space and atmospheric sciences and solar-system studies.
The Kodaikanal Solar Observatory is one of India's historic solar-observation facilities and has a long record of sunspot and solar activity observations.
Key facts for Prelims
Magnetosphere: Region around Earth where the planet's magnetic field dominates and provides protection from much of the charged-particle radiation associated with solar activity.
L1 Lagrange Point: The Sun–Earth L1 point is located between the Sun and Earth, where the gravitational forces and orbital motion allow a spacecraft to remain in a relatively stable position with respect to the two bodies.
It provides an uninterrupted view of the Sun, making it highly useful for monitoring solar flares, CMEs and solar wind before they reach Earth.