2017-07-13 / Front Page

Perseids meteor shower will give stargazers a show July 17-Aug. 24

Start saving up a few good wish­es, because the Perseids meteor shower – named one of the “most popular meteor showers of the year” by NASA meteor expert Bill Cooke – will take place from July 17-August 24, giving skywatchers an entire summer to catch a glimpse of a shooting star or two.

While the peak of the meteor shower won’t take place until mid- August, wandering shards will be visible before and after that point, making for an exciting summer filled with star-spotting possibili­ties.

At peak times, rates of about 80 meteors an hour are predicted. If it’s an “outburst” year, like last year was considered, anywhere from 150-200 meteors an hour could potentially shoot across the sky. This shower is all due to the earth passing through the path of Comet Swift-Tuttle.

The Comet Swift-Tuttle was dis­covered by Lewis Swift and Horace Parnell Tuttle, curiously enough, independently, as both astronomers spotted the comet three days apart in 1862.

Considered a “periodic comet,” Swift-Tuttle supposedly has an orbital period of 133 years, and is deemed a “Halley-type” comet due to its frequent circulation.

“Comet Swift-Tuttle is the largest object known to repeatedly pass by Earth; its nucleus is about 16 miles (26 kilometers) wide,” space.com writer Sarah Lewin recently penned. “It last passed nearby Earth during its orbit around the sun in 1992, and the next time will be in 2126. But it won’t be forgotten in the meantime, because earth passes through the dust and debris it leaves behind every year, creating the an­nual Perseid meteor shower.”

Considering the peak time in August when the most stars can be seen, this period can be attrib­uted to the densest, dustiest area of Comet Swift-Tuttle’s residual tail, and earth’s travel through this thick zone.

Lewin further explained that, “when you sit back to watch a me­teor shower, you’re actually seeing the pieces of comet debris heat up as they enter the atmosphere and burn up in a bright burst of light, streaking a vivid path across the sky as they travel at 37 miles (59 km) per second. When they’re in space, the pieces of debris are called ‘meteoroids,’ but when they reach earth’s atmosphere, they’re designated as ‘meteors.’ If a piece makes it all the way down to earth without burning up, it graduates to ‘meteorite.’ Most of the meteors in the Perseids are much too small for that; they’re about the size of a grain of sand.”

Accompanying the majesty of the Perseids meteor show is the peak of the Delta Aquarid meteor shower, which is set to scatter at the end of the month, between July 27-28.

As EarthSky’s Bruce McClure and Deborah Byrd explain, the shower will actually begin with steady rambles on July 12, wrap­ping up near the end of August, however given it’s timeline, it will have to compete with both the Perseids meteor shower, as well with several amazingly wide and waxing crescent moons set to occur, unfortunately right around Delta Aquarid’s peaking point.

“Typically, this shower produces the most meteors in the predawn hours and overlaps with the more famous Perseid meteor shower. So you might see a few Perseids in the mix,” McClure and Byrd said. “About five to ten percent of the Delta Aquarid meteors leave per­sistent trains – glowing ionized gas trails that last a second or two after the meteor has passed. The meteors burn up in the upper atmosphere about 60 miles (100 km) above the earth’s surface. Watch for their lingering trains!”

With this many astronomical wonders taking place throughout the summer, it seems that a spec­tacular means of free, yet peace­ful, entertainment is awaiting avid stargazers or casual onlookers alike, so keep your eyes peeled for a well- anticipated season of shooting stars as they cascade through the July and August skies.

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