The sight of a bright, colour­ful ring around the sun caused a stir through­out the coun­try yes­ter­day. The un­usu­al sight, which was vis­i­ble for sev­er­al hours, had cit­i­zens paus­ing dur­ing their Sat­ur­day morn­ing chores and shop­ping to gaze up at the sky. Sev­er­al per­sons were seen tak­ing pho­tos. It even caused an on­line fren­zy, with rapid fire ex­changes of text mes­sages and pho­tos via mo­biles, as well as post­ings of pic­tures and com­ments on pop­u­lar net­work­ing sites. How­ev­er, while the ap­pear­ance of a ring around the sun is not a fre­quent oc­cur­rence, it is not un­com­mon. What was vis­i­ble over Trinidad and To­ba­go yes­ter­day was a ha­lo, al­so known as a nim­bus, ice­bow or glo­ri­ole. It is as­so­ci­at­ed with clouds called cir­ro­stra­tus which are com­posed of ice crys­tals and usu­al­ly form at al­ti­tudes above 20,000 feet.

Dr Shirin Haque, se­nior lec­tur­er and as­tronomer in the De­part­ment of Physics at the Uni­ver­si­ty of the West In­dies (UWI), said the ha­lo around the sun is per­fect­ly nor­mal and is due to the ice crys­tals sus­pend­ed in the clouds. "The ice crys­tals act like tiny prisms, re­fract­ing the light from the sun and split­ting it up in­to the rain­bow colours due to dis­per­sion. The con­di­tions just hap­pened to be right for there to be such a beau­ti­ful ha­lo around the sun," she ex­plained. "Ha­los around the sun do not hap­pen too of­ten but cer­tain­ly are not an un­com­mon phe­nom­e­na at all." She, how­ev­er, warned: "Look­ing at the sun di­rect­ly for any length of time, can cause per­ma­nent eye dam­age. Nev­er at­tempt to look at a ha­lo di­rect­ly, or for a long pe­ri­od of time." A ha­lo was last seen in this coun­try in South Trinidad in Ju­ly 2011. Sight­ings have been re­port­ed in re­cent days in places as far flung as Malaysia and Cal­i­for­nia in the Unit­ed States. In folk­lore, a ha­lo around the sun or the moon means rain is com­ing. They have been record­ed as far back as the be­gin­ning of the fourth cen­tu­ry.