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Where’s the radiant point for the Perseid meteor shower?

The Perseid meteors are named for the constellation Perseus the Hero. If you trace the paths of the meteors backwards, they seem to radiate from this constellation.

Tonight for August 13, 2015

From late night until dawn, watch for the 2015 Perseid meteor shower – August’s famous shower of shooting stars. People always ask which direction they should watch to see a meteor shower. The answer is that any direction will do. It’s true that the 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, especially between midnight and dawn. Still, it’s fun to find the radiant. More about that below.

Before tonight’s meteor shower even begins, look for the golden planet Saturn (and the star Antares) in the south to southwest sky as darkness falls. (From the Southern hemisphere, look for Saturn and Antares high overhead at nightfall. From either the Northern or Southern hemisphere,, don’t expect a significant number of Perseid meteors to fall until after Saturn sets in your southwest sky (late evening from mid-northern latitudes or after midnight at southerly latitudes).
Typically, the most meteors streak the starry heavens during the predawn hours, offering perhaps up to 50 or more meteors per hour at mid-northern latitudes.

By astronomers’ best estimates, the night of August 12-13 (mornings of August 12 and 13) will probably feature the most abundant display of Perseid meteors. But the night before (August 11-12) and after (August 13-14) should be fine for watching the usually reliable summer meteor shower. Will you see that many tonight? Only way to find out is to look. Find a dark sky away from pesky artificial lights, and lie down comfortably on a reclining lawn chair.

As evening deepens into late night, the meteor numbers will start to increase. The intensity will pick up after midnight, and the greatest numbers of meteors usually bombarding the sky in the dark hours just before dawn. A typical count is 50 an hour. You might see more.

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.

Mira the Wonderful, the famous variable star, may – or may not – be visible

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 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 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 the path of a Perseid meteor backward, you will find that it radiated from a point in the sky within the boundaries of the constellation Perseus.

Double Cluster in Perseus: Two star clusters

View larger. | Here’s another cool Perseid photo – actually a series of images stacked. These were Perseid meteors seen in 2010 by EarthSky Facebook friend Photography by Daniel McVey. See more of his work here.

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 – like it is this year – this shower reliably produces 50 or more meteors per hour at its peak at northerly latitudes, or an average of about one a minute.

Fortunately, in 2015, the thin waning crescent moon coming up shortly won’t intrude on this year’s Perseid smeteor hower.

Bottom line: The bright starlike object near tonight’s moon is really a planet, Venus. You can also find Saturn this evening. Late night or between midnight and dawn, 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 August 12 and 13. The morning of August 14 might feature a good display of Perseid meteors, as well.

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