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Friday, February 18, 2011

The largest solar flare of cycle 24


Our Sun has a number of spots on it called sunspots which are due to the strong magnetic field and plasma in the Sun. The rotation of Sun is not uniform, it has different rate at poles than at equator; this makes the rotation 'differential'. The differential rotation of Sun creates the twisted and complex magnetic field and as a result of that sunspots are produced (this is not as simple as it has been mentioned here, but it may make sense to a layman). The temperature of a sunspot is less than the solar average temperature that is why they appear as a 'spot' with 'cooler' degree.

The number of these sunspots varies and it is a well documented feature that the Sun follows an eleven year cycle with the number of spots ranging from 0 to 170. This cycle is called the Solar Cycle. Since the time these cycles have been recorded the Sun is in Cycle 24 these days; it started back in Dec 2008. The list of all Solar Cycles can be seen here.

One of the phenomena associated with this Solar Cycle is the eruption of the mass from the corona of Sun, i.e., the 'plasma atmosphere' of Sun. Due to the complex magnetic field patters and these sunspots the Sun erupts mass which is termed as Coronal Mass Eruption (CME). This mass eruption may or may not be alone and most of these eruptions are followed by energy eruption also in the X-ray range. Technically speaking this X-ray burst is called a solar flare or X-ray flare.

These flares are one of the routine phenomena of Sun but their frequency varies with the sunspots. These days one of the sunspots in the Southern hemisphere of the Sun has gone made and it generated a strong flare and the CME entitled as 'Valentine's Day Solar Flare' by NASA. The image of this recent flare is given below. (Image source NASA). The brightest region is erupting this flare. This is the largest flare of the current Solar Cycle, till today.
These flares or radiation storms have adverse effect on satellites, electrical grid stations on higher latitudes of Earth and the HF Communication because a radio blackout may occur as one of the consequences at all latitudes of Earth.

The Sci-Fi 2012 shows the end of world due to heating of the inner layers of the Earth, but scientifically speaking these solar flares have nothing to do with the climate and/or weather pattern on Earth, these flares disturb the weather is space and the documented adverse effects have been mentioned above.

The Universe would naturally come to an end and so as the Earth also being its part, but such solar flares may not be the reason for the same. Our Earth is being shielded by a magnetic field and it is capable enough to weaken such flares and the other outer space hittings.

Further readings: British Geological Survey Analysis of the recent flare, A 12-hour long geomagnetic storm, And the Sun wakes up