‘Solar halo’ creates flutter – Siliguri sees rare phenomenon
Posted by barunroy on September 11, 2008
Solar Halo – Photo by Prakash Mundra
FROM THE TELEGRAPH
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| The solar halo in the Siliguri sky on Wednesday. Picture by Kundan Yolmo |
Siliguri, Sept. 10: A halo around the sun seen from Siliguri this morning triggered curiosity as well as rumours as it coincided with the start of the Big Bang experiment in Geneva.
When the aura around the sun became visible around 11.30am, the people of the town started making calls to their near and dear ones, trying to gauge what exactly the phenomenon was.
“I was amazed to see a light around the sun when I went to the terrace to lay some clothes. I hadn’t seen such a scene before. Soon, I received a call from my friend who wanted to share the excitement of having witnessed the rare phenomenon,” said Proloy Choudhury, a college student.
The experts said it was an optical astronomical phenomenon generally not seen in city skies.
“We have seen the picture of the sun in the Siliguri sky today and feel that it was probably a solar halo. Such auras are created mostly when sunlight is refracted through ice crystals formed in cirrus or cirrostratus clouds moving at an altitude of 5-10km in the upper troposphere,” Sanjib Sen, the director of the Positional Astronomy Centre in Calcutta, said over the phone from Calcutta.
“A particular shape and orientation of the crystals are responsible for the formation of the halo. There will be different colours when the light refracted by the crystals is split,” Sen added.
Debasis Sarkar, the secretary of the Sky Watchers’ Association of North Bengal, said such halos were not commonly seen in cities because of high accumulation of dust and smog in the sky.
“The ice crystals are usually hexagonal in shape which refract the light. The halos are seen in full circular shape and of lesser diameter than a rainbow,” said Sarkar.
He added that the halo might have been formed in the Siliguri sky because of heavy rain early in the morning and bright sunshine afterwards with very little air movement.
Ruma Bhattacharya, a housewife, said: “I was already tense after I heard that the Geneva experiment would be the end of the world. The aura around the sun only added my fears.”
The test in Geneva, which started today, will see two beams of protons zipping in opposite directions at more than nine-tenths the speed of light collide inside a tunnel. The test kicks off a fresh search for an elusive piece of a decades-old physics puzzle by mimicking conditions a whisker of time after the birth of the universe.
