Every time there’s a meteor shower, people always ask which direction they should watch. The answer is that any direction will do! It’s true that this weekend’s Perseid meteors appear to radiate from a single point in the sky. But you don’t need to look toward this radiant point to see the meteors. Instead, the meteors will appear all over a dark night sky during the next several nights. Still, it’s fun to find the radiant. More about that below.
Before tonight’s meteor shower even begins, look for the waxing crescent moon plus the planets Venus and Saturn at dusk and early evening. The meteors won’t really fly in significant numbers until Saturn has already set by mid to late evening.
By astronomers’ best estimates, the night of August 11-12 will probably feature the peak night of the Perseid shower in North America. In Asia, the peak night might come later, on the night of August 12-13. But any clear night from here on out should be fine for watching this reliable summer meteor shower. Last year, observers under dark skies reported over 60 meteors an hour, according to the International Meteor Organization. Will you see that many tonight? Only way to find out is to look.
As evening deepens into late night, the number of meteors will start to increase. The intensity will pick up after midnight, and the greatest numbers of meteors typically bombard the sky in the dark hours just before dawn. A typical count is 60 an hour. You might see more. Plus the planets Jupiter and Mars will rise into the eastern sky before dawn.
Appreciably south of the equator, the count will be less – perhaps 10 to 15 meteors per hour. Also, at southerly latitudes, the first Perseids probably won’t appear until midnight or the wee hours of the morning. That’s because the constellation Perseus – the radiant point for the Perseid meteors – is a far northern constellation. Perseus rises earlier in the evening and climbs higher in the sky at northerly latitudes.
That’s the constellation Perseus the Hero at the top of this post. It’s the reason this meteor shower is best between the hours of midnight and dawn. One way to think about it is this. The shower’s radiant point – the point in the sky from which the meteors appear to radiate – needs to be above your horizon before you can see the most meteors. At this time of year, the constellation Perseus ascends appreciably high in the northeast by about midnight and highest in the sky before dawn. The Perseid meteor shower is named for this constellation.
Do you have to be able to identify the radiant point, or the constellation Perseus, to see the meteors? No. The meteors will appear in all parts of the sky – especially between midnight and dawn on the mornings of August 11, 12 and 13. If – just for fun – you do want to spot Perseus, look first for the W-shaped constellation Cassiopeia. The constellation Perseus is faint, but Cassiopeia is noticeable and can help you find it. If you do see a Perseid meteor, and trace its path backward, you will find that it radiated from a point in the sky within the boundaries of the constellation Perseus.
Many people look forward each summer to the Perseids. It’s a great time to go camping. This shower always peaks around this time of year, and in years when the moon is out of the sky, it reliably produces 50 or more meteors per hour at its peak at northerly latitudes, or an average of about one a minute. Fortunately, the rather thin waning crescent moon in the predawn hours won’t really intrude too greatly on the 2012 Perseid shower. Instead, the moon will enhance the show, guiding your eye to the sky’s two brightest planets, Venus and Jupiter, and to the constellation Orion in your eastern sky. If you live in Indonesia, you may even see the moon occult – cover over – Jupiter before sunrise on Sunday, August 12.
Find a dark, open spot away from pesky artificial lights, sprawl out comfortably on a reclining lawn chair and enjoy the best nights of the Perseid shower. The meteors will probably fall most abundantly – from anyplace worldwide – from about 2 a.m. until dawn on Monday, August 12. But the nights before and after should feature good meteor displays, too.