Friday,  May 3, 2013 • Vol. 14--No. 287 • 16 of 29 •  Other Editions

See Eta Aquarid meteor shower before dawn May 4 and 5

• The Eta Aquarid meteor shower is now peaking in the wee hours before dawn. Its maximum is expected to come in the predawn sky on Sunday morning - May 5, 2013 - in the dark hour before astronomical twilight. Don't know when astronomical twilight begins in your sky? Find out with this handy custom sunrise-sunset calendar.

• Under ideal conditions, the Eta Aquarid meteor shower produces up to 20 to 40 meteors per hour - or possbly even higher meteor numbers in the Southern Hemisphere. Luckily, the thin waning crescent moon will not seriously intrude on this year's Eta Aquarid shower. Although the more southerly latitudes have the better view of this shower, tropical and subtropical latitudes in the Northern Hemisphere still enjoy a decent view of the Eta Aquarids. North of 40o latitudes the meteors numbers tend to be few and far between. But no matter where you live worldwide, the greatest number of meteors usually fall in the dark hours just before dawn.
• The point in the sky from which meteors in annual showers appear to radiate is called the meteor shower radiant. You don't have to locate the radiant to watch the Eta Aquarid meteors, but people always ask about them. Although the Eta Aquarid meteors streak all over the sky, they appear to radiate from the Y-shaped group of stars called the Water Jar. The Water Jar is part of the constellation Aquarius.
• To star-hop to the Water Jar, first of all find the four stars of the Great Square of Pegasus. (See sky chart at bottom right.) Looking eastward at about 4 a.m. (Daylight Saving Time), the Great Square of Pegasus glitters like a celestial baseball diamond. Imagine the bottom star as home base. Draw a line from the third base star through the first base star, then go twice that distance to locate the star Sadal Melik.
• To the lower left of Sadal Melik is the small Y-shaped Water Jar, marking the approximate radiant of the Eta Aquarid meteor shower. Again, you don't need to know the shower's radiant point to watch the meteors! During the wee morning hours before dawn, the meteors in this annual shower will appear in all parts of the sky.

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