IN southern Nigeria, cloud cover often affects sky watchers, in much the same way women in jeans trousers now affect men. It deprives them of highly valued visual stimulation.This, in fact, is what happened to me, during the celebrated Quadrantids shower.The Quadrantids start each year around December 28 and end between January 7 and 13 (astronomers differ on closing dates). But the peak nights are the 3rd and the 4th, when an observer, who happens to be in the right place, reportedly can see up to 120 streaks in 60 minutes.Yet I came no closer to seeing a meteor, on either of these nights, than a Nigerian male would to encountering a female in feminine attire.Only on the evening of the 5th, did I observed what may have been a faint flash in the obscuring veil of haze and vapour that hung over Port Harcourt, Rivers State.As if to rub salt into an open wound, I could sit in front of my laptop and watch Quadrantids meteors streaking across clear skies over the eastern U.S. ' thanks to the space agency, NASA, whose website provide live coverage. It even captured the rare occurrence, of two parallel meteors.In any event, I'm pleased that sky-watchers elsewhere were not disappointed. Indeed, according to some Internet headlines, the Quadrantids put on quite a show ' living up to their reputation as one of the most spectacular meteor showers of the year.But there is no need for Nigerian enthusiasts to despair. Quadrantids was simply a fanfare, the opening flourish of the 2012 meteor season. This year, meteor astronomers predict a rich visual harvest, including some displays that can even rival the Quadrantids.Happily, in 2012 the Moon will, at critical viewing times, keep a low profile ' producing darker night skies when viewers need them most.I will provide more details in subsequent installments and also preview a few major, as well as some minor, showers. The idea, is to help Sky-watchers plan their itineraries for the coming months.During a meteor shower, the sky is alight with shooting stars. On any other night, an observer might see six to 10 streaking lights in an hour. But showers produce vastly increased sighting rates.The Meteor Data Centre of the International Astronomical Union (IAU) has 427 listings. But this includes both major and minor showers, as well as non-visual events. Non-visual showers are mainly of interest to radio astronomers. Minor displays have a low yield and can thus turn neophytes off.Accordingly, the International Meteor Organisation (IMO), a world body for amateurs, posts a Working List of 33 Visual Meteor Showers. Its ephemeris is intended primarily for naked-eye observers.The three superstars in this lineup are the Quadrantids, Perseids and Geminids displays. Ranked just below them, is a second tier of major showers that are also very entertaining. Roughly, a 'major' shower has an average zenithal hourly rating, or ZHR, of 10 or more meteors.Outside the IMO though, there is little agreement, either on the number of majors or which meteor displays fall in the group. The Collins Dictionary of Astronomy, for example, lists 19 while, in Astronomy: Journey To The Cosmic Frontier, John D. Fix includes only eight.To be continued.
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