Solar tantrum after 11 years makes scientists nervous

Solar tantrum after 11 years makes scientists nervous
SAIKAT DATTA

PUNE, SEPT 3: Two solar eruptions monitored earlier this week by NASA and solar monitoring agencies has had anxious scientists fixing their gaze on the sun, studying the possible adverse effects these bursts could have on earth communication satellites and networks.

A solar flare erupted on early Tuesday followed by a Coronal Mass Ejection (CME), something that is akin to a volcano erupting on earth. And a CME packs far more punch than all the volcanoes on earth erupting at the same time.

Similarly, scientists say that a solar flare is the solar system's largest explosive event and is equivalent to nearly 40 billion Hiroshima-sized atom bombs.

Observations over a long period of time have shown that satellites are the worst affected during the release of energy particles by this phenomenon. High-frequency communications and power-grids are also affected in a significant manner, a major cause for concern especially in countries in the northern hemisphere.

In fact, when the resultant energy particles move towards the earth the orbiting satellites would be in for a severe bashing. ``Earth stations keep their satellites in the sleep mode to protect them against any contamination,'' says S Ananthakrishnan of the National Centre of Radio Astrophysics and Observatory director at the Giant Metrewave Radio Telescope near Pune. Indian satellites, if they are in the line of fire (on the sunlit side), could also be affected.

According to the web site www.solcumhouse.com (which recorded the event), this is the period of the ``solar maximum,'' a phenomenon that happens every 11 years. According to the site, ``NASA warns that solar disruptions like those of 1989 (when the event last occurred) may soon return.''

But the damage could be a lot more this time round as technology has taken several quantum leaps and more hi-tech the equipment, the more vulnerable it gets. ``Society is much more vulnerable because so much technology orbits the earth today. Hundreds of satellites, most of them for telecommunications, have been launched since 1989,'' the site reports.

A worst-case scenario shows that it could knock out all high-frequency radio on the sunlit side or expose aircraft passengers in northern latitudes to the equivalent of 100 x-rays.

And since both eruptions have taken place recently, the effects of the phenomenon could be felt on earth in the next few days. ``Both together would mean a major solar storm activity and depending on the speed of the particles, they could affect earth's radiation belt soon,'' says Prof H M Antia at the Tata Institute of Fundamental Research (TIFR), Mumbai.

``But please do not think that it is doomsday,'' says Ananthakrishnan. According to him, past observations have shown that high-frequency communication was disrupted and satellites were severely affected.

In fact, in the last solar storm observed between July 14 and 19 this year, the Japanese ASCA research satellite shut down due to increased atmospheric drag. Another Japanese satellite, the Akebono, suffered high energy particle hits on its electronic components disrupting the spacecraft's computer operations.

Other strange events were also reported during this period. Power transmission in many parts of the US reported widespread capacitor bank tripping and one company even had 15 amps of electricity flowing on a neutral current-free leg of a transformer.

``Although we have been observing this phenomenon for many centuries, we have not even begun to understand it,'' says Ananthakrishnan.

In India, the Udaipur-based solar observatory will be keeping a close watch on the Sun's activity period alongwith the Ooty Radio Telescope, both trying to fathom where we stand when the solar system's biggest energy pool throws around a few tantrums every 11 years.