The Sun has unleashed four massive solar flares in two days, each emitting energy equivalent to a billion hydrogen bombs. The latest flare on Wednesday might cause geomagnetic storms on Earth affecting satellites and communications systems.
Four significant X-class solar flares left the Sun in just 48 hours, sending powerful bursts of radiation into space, according to Space Weather website.
The first burst of solar energy was detected on Monday at 2:00 GMT. Fourteen hours later the Sun emitted a stronger X2.8-class flare, peaking at 16:05 GMT, according to NASA.
The third flare occurred in under 24 hours, peaking at 2:11 GMT and was classified as an X3.2 flare, the strongest X-class flare of 2013 so far. The latest X1.2-flare occurred on Wednesday at 01:52 GMT.
All of the flares were tens of times the size of Earth, originating from an AR1748 sunspot, an active region just out of sight over the left side of the Sun.
The flares were associated with a solar phenomenon, called a coronal mass ejection (CME). Although the sunspot is not directly facing Earth, the last flare produced a CME with an Earth-directed component, the Space Weather website reports.
If the flares associated with CME are directed at Earth they can cause long lasting radiation storms, according to NASA.
When CME occurs it propels bursts of billions of tons of solar particles and electromagnetic fluctuations that can reach Earth’s atmosphere and harm satellites, communications systems, and even ground-based technologies and power grids.
The March 1989 CME produced by a X15-class solar flare resulting in a geomagnetic storm that caused the collapse of Hydro-Québec’s electricity transmission system in Canada.
The latest 2013 flares were of X-class that denotes the most intense flares. The smallest ones are A-class, followed by B, C, M and X. The number that follows the class provides information about its strength. An X2 is twice as intense as an X1, an X3 is three times as intense, and so on.
According to NASA the most powerful flare measured by modern methods occurred on November 4, 2003 during the previous solar maximum. It was so strong that the sensors were cut off when estimating the burst of radiation at X28.
Solar activity is currently ramping up toward what is known as solar maximum, which is expected in 2013. The solar maximum occurs approximately every 11 years.
“However, this same solar cycle has occurred over millennia so anyone over the age of 11 has already lived through such a solar maximum with no harm” said NASA in a statement.
The coming solar maximum explains the increased numbers of flares. The largest X-class flare in this cycle so far was an X6.9 on August 9, 2011.
The solar cycle was discovered in 1843 and scientists have been tracking it ever since.