The Solar Flare is the giant explosion erupted on the surface of the Sun. In other words, Solar Flare can be defined as sudden, rapid, and intense variation in brightness on the surface of the Sun. It was first recorded on the 1 September, 1859 by two scientists- Richard Hodgson and Richard Carrington.
Classification of Solar Flare
Solar Flare is a sudden and intense explosion of magnetic energy. Hence, it is categorised into five categories to specify wavelengths of electromagnetic radiation which are given below:
1. A: <10-7 [(in watts per square metre, W/m2) of 1 to 8 Angstroms X-rays near Earth] It is lowest intensity solar flare.
2. B: ≥10-7 <10-6 [(in watts per square metre, W/m2) of 1 to 8 Angstroms X-rays near Earth] It is lowest intensity solar flare.
3. C: ≥10-6 <10-5 [(in watts per square metre, W/m2) of 1 to 8 Angstroms X-rays near Earth] It is minor solar flare and have no effect on the Earth because coronal mass ejections are slow, weak and rare.
4. M: ≥10-5 <10-4 [(in watts per square metre, W/m2) of 1 to 8 Angstroms X-rays near Earth] It is medium large solar flare which causes solar radiation storms that can be experience aurora on the middle latitudes.
5. X: ≥10-4 [(in watts per square metre, W/m2) of 1 to 8 Angstroms X-rays near Earth] It is biggest and strongest solar flare that can cause severe (G4) to extreme (G5) geomagnetic storming at Earth.
What causes Solar Flare?
As we know that the Sun is more or less hot plasma with internal convective motion that generates a magnetic field via a dynamo process. During the dynamo process, the fast moving charged particles of the plasma medium in the solar atmosphere interact each other which causes a sudden burst of energy which increase the speed of particles that creates coronal mass discharge. The interactions are so intense that results the transformation of energy from magnetic to kinetic.
The Solar Flare occurs in the active zones around sunspots (cooler, darker spot appearing periodically on the sun's photosphere; associated with a strong magnetic field). The energy generated during the eruption of solar flare can be equated on the energy generated by the millions of 100-megaton hydrogen bombs burst at same time.
Occurrence and Effects of Solar Flare
The intensity and occurrence of the solar flare varies time to time. For Example- Solar flare occur several times when Sun is active in a day time. In fact, the occurrence of solar flare is very frequent but sizes of the flare may vary. Smaller flares are more frequent than bigger solar flares. It can be seen when X- Rays and other radiations affect the planet’s ionosphere leading to a disruption in long-range communication services.
Can Solar Flares Be Seen From Earth?
The Solar Flare affects all the layers of the solar atmosphere (photosphere, chromosphere, and corona) which means it crosses all the wavelengths of the electromagnetic spectrum (an n ordered array of the components of an emission or wave). This eruption accompanied by the full of energy in the form of radio waves, gamma rays, and several others that are cannot be seen by the naked eye. So it is not possible to see the electromagnetic radiation without specialised tools and equipment.