eta-aquarid

Eta Aquarid meteors over New Zealand this week, photographed by Stephen Voss over the course of 90 minutes.

Every spring, Earth crosses the orbital trail of Halley’s Comet. While we’ll have to wait until 2061 to see the actual comet again (I am old enough to remember seeing it back in 1986, though, so nah!), each year we get a fresh sprinkling of comet tail dust into our atmosphere at 150,000 mph. As Earth whips through, the debris appears to radiate out from the constellation Aquarius, which is evident in the photo above.

It’s a coincidence, but a beautiful one. Read more about the Eta Aquarids at EarthSky and Bad Astronomy.

We’re pleased to inform southern (and northern) skywatchers that one [upcoming] meteor shower in particular – the Eta Aquarid shower – is a fine one to view from both northerly and southerly latitudes. No matter where you live, you can watch the Eta Aquarids in early May. Plus the moon is not a problem for this shower this year!

The 2013 Eta Aquarid meteor shower is expected to produce the greatest number of meteors in the dark hours before dawn on Sunday, May 5. However, the broad peak of the Eta Aquarid shower may present similarly strong showings during the predawn hours on Saturday, May 4, and Monday, May 6. In a dark sky, especially at more southerly latitudes, the Eta Aquarids can produce up to 20 to 40 meteors per hour. From mid-northern latitudes, you might only see about 10 meteors per hour.

•Radiant point of the Eta Aquarid shower.

"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.” via EarthSky

•What’s the source of Eta Aquarid meteor shower?

"Every year, our planet Earth crosses the orbital path of Halley’s Comet in late April and May, so bits and pieces from this comet light up the nighttime as Eta Aquarid meteors at this time. This shower is said to be active from April 19 to May 20, although Earth plows most deeply into this stream of comet debris around May 5 or 6.

The comet dust smashes into Earth’s upper atmosphere at nearly 240,000 kilometers (150,000 miles) per hour. Roughly half of these swift-moving meteors leave persistent trains – ionized gas trails that glow for a few seconds after the meteor has passed.

Our planet also crosses the orbital path of Halley’s Comet at the other end of the year, giving rise to the Orionid meteor shower, which is forecasted to peak on October 21, 2013.

Give yourself at least an hour of viewing time for watching any meteor shower. Meteors tend to come in spurts that are interspersed by lulls. Also, it can take as long as 20 minutes for your eyes to adapt to the dark.

•Find out more about the Eta Aquarid meteor shower here, here, and here. To find out where to look based on your location take a look at the  Northern Hemisphere & Southern Hemisphere sky maps.