A celestial traffic jam may be on tap this week as two meteor showers combine forces to put on a brilliant sky show.
One of the best shooting star events of the year is the annual August Perseid meteor shower. (See Perseids pictures.) However this year's peak, on August 12, happens to coincide with a bright full moon—drastically cutting down the number of meteors visible to the naked eye.
Yet while the main event might be blocked out by the blinding moonlight, the opening act promises to be much better.
This year the lesser known Delta Aquarid meteor shower is expected to peak on Friday night, when the Delta Aquarids' more productive Perseid cousin is just starting to ramp up.
Together the showers will produce anywhere between 15 and 30 shooting stars per hour under clear, dark skies.
"While the moon is set to be an unpleasant guest for the Perseid peak, skywatchers are not out of luck as the Delta Aquarids could be one of the best meteor showers of the year," said Raminder Singh Samra, astronomer at theH.R. MacMillan Space Centre in Vancouver, Canada.
"The new moon during the peak of the Delta Aquarids may actually allow for a much more spectacular display."
Meteors Visible With Naked Eye
Like most meteor showers, the Delta Aquarids and Perseids are both caused by Earth's atmosphere slamming into clouds of sand grain-size particles shed by orbiting comets. Each particle enters the atmosphere at speeds in excess of 93,200 miles (150,000 kilometers) an hour, only to burn up in a fleeting streak of light.
On average, the Perseids begin falling at a rate of around five meteors per hour. They're visible for a couple of weeks before mid-August, when they peak at hourly rates of 60 to 120 meteors.
While the Delta Aquarids are considerably more modest, the simultaneous activity during the last days in July and early August will produce the best chance for meteor observers to see a lot of shooting stars during either shower.
Most people around the world can see the showers, best seen with the naked eye in a dark, rural area away from city lights. Since meteors will be streaking across the overhead skies, lie down on a blanket or recline in a lawn chair and allow your eyes to become adapted to the darkness, Samra suggested.
"Meteor shower activity always increases as the night progresses towards dawn. If you are a night owl, then staying up to catch a more spectacular show might be worth it."
Perseids Peak May Still Offer Eye Candy
But all may not be lost with the Perseids—observing the sky show a few days before the August 12 peak may work too, noted astronomer Geza Gyuk of the Adler Plaentarium in Chicago.
"For example, on the night of the ninth, morning of the tenth, there will be a couple hours after the moon has set [about 2 a.m. local time] and before the morning twilight begins when it's close enough to the peak that one might expect 15 per hour."
Likewise, the 2011 Perseids peak may still be good for some astronomical eye candy.
"They are also known for the occasional nice fireball with a long-lasting 'smoke trail,'" Gyuk said. "If we get more of these than usual, then even moonlight won't spoil the fun."