Solar Tsunami

Last year solar astronomers observed quietest Sun in almost a century. In 2008, there were no sunspots observed on 266 of the year's 366 days (73%). To find a year with more blank suns, you have to go all the way back to 1913, which had 311 spotless days, some observers suggested that the solar cycle had hit bottom in 2008. Sunspot counts for 2009 were almost same as previous year 260 spotless days (71%). Many astronomers said that our sun is now passing through the deepest solar minimum. But, a few days ago suddenly the Sun emitted a massive belch in to space, astronomers christen it Solar Tsunami.

On August 1st at 8:55 Universal Time, orbiting satellites witnessed a sizable flare erupting from the large sunspot region designated 1092. The strength of this outburst was pegged at C3, modest as flare go, but it still triggered an impressive coronal mass ejection, or CME, that shot out from the solar disk at more than 1000 km per second. The CME hit Earth's magnetic field on August 3rd at 1740 Universal Time. The impact sparked a G-2 class geomagnetic storm that lasted nearly 12 hours--time enough for auroras to spread all the way from Europe to North America.

CMEs are the result of strong solar activity or solar storms. It is a large cloud of charged particles that are ejected from the Sun over the course of several hours and carry up to ten billion tons of plasma. They expand away from the Sun at speed as high as a thousand kilometres in second. A CME can make the 150 million kilometres journey to Earth in just two to four days. This CME will have noticeable consequences beyond producing an aurora. Stronger solar storms could cause adverse impacts to space based satellites, space station and technological infrastructure on Earth.

The Sun goes through a regular activity cycle about 11 years long. The last solar maximum occurred in 2001 and its recent extreme solar minimum was particularly weak and long lasting. Experts don't expect solar activity to peak until mid-2013, but these kinds of eruptions are one of the first sign that after oversleeping for more than a year, our star is finally stirring from hibernation and heading toward anther solar maximum expected in the 2013 time frame.

AMOL KATE