With the Southern Delta Aquarid meteor shower peaking tomorrow morning, the summer meteor season’s officially underway. While not a spectacular shower from mid-northern latitudes, why not chance a look anyway. With a rate of 10-15 per meteors an hour from a dark sky you’re bound to catch at least a few.
The farther south you live, the better it gets. Observers in the southern hemisphere can expect double that number because the shower’s radiant will be much higher in the sky. Any meteors flashing south of the radiant won’t get cut off by the southern horizon like they do further north.
The annual shower gets its name from Delta Aquarii, a dim star in the dim zodiac constellation Aquarius. You don’t need to know the constellations to enjoy a meteor shower but it doesn’t hurt to know the general location of the radiant, the point in the sky from which the meteors appear to radiate. If you can trace the path of a meteor backward toward Aquarius, chances are it’s an Aquarid.
There are actually two meteor showers in Aquarius active this time of year – the northern and southern Delta Aquarids. The northern version sports fewer meteors and peaks in mid-August.
The Southern Deltas peak over the next two mornings – July 29 and 30. Both serve as warm-ups for the upcoming Perseid meteor shower that climaxes on August 12.
Tonight’s shower will suffer no interference from moonlight, making this an ideal time for meteor watching. Unfortunately, Perseid rates will be reduced by a bright waning gibbous moon. Don’t be surprised though if you see a few Perseids while you’re out. The shower’s just become active. If you can draw a meteor’s trail back to the northeastern sky, it just might be one. Perseids are also known for leaving bright streaks in their wake called trains.
Nearly all meteor showers originate from clouds of sand to seed-sized bits of debris spewed by vaporizing comet ice as they swing near the sun. The Delta Aquarids may trace its origin to dust boiled off Comet 96P/Machholz.
The best time to watch the shower is in the early morning hours before dawn when the radiant rises in the south-southeastern sky above the bright star Fomalhaut. Try to get away from city lights. Point your lawn chair south and spend some time in heavenly contemplation as you wait for Aquarius to toss a few javelins of light your way.