The Perseid meteor shower is the most widely observed and dependable annual meteor display of the year, and its peak this week has all the earmarks of being an excellent example of celestial fireworks, weather permitting.
This year, the of Wednesday and Thursday (Aug. 12 and 13) just one day before the new moon. Unlike last year, when a brilliant and nearly full moon washed out all but the brightest meteors, 2015 should be a very opportune year for observing "shooting stars" with your own eyes or cameras. Today, NASA released a .
Another reason that the Perseids could put on a better-than-average show this year is an assist from the planet Jupiter. We'll explain why that is in moment. First, here is a primer about where famous meteors like the Perseidscome from. []
Pieces of a cometPerseid meteor shower is no different. It is made of pieces of Comet Swift-Tuttle, a comet first discovered in 1862 that takes 133 years to make one trip around the sun. Comet Swift-Tuttle was last visible in the night sky in 1992 and won't return until 2126.
Comet Swift-Tuttle must have passed the sun well over 1,000 times to produce the present stream of Perseid meteors. The comet debris has become distributed all around the Swift-Tuttle's elongated elliptical orbit, which reaches out beyond the realms of Pluto and ultimately brings them back to intersect Earth's orbit at almost a right angle, producing a that lasts for several days in mid-August
But on those occasions when the planet is passing closest to Swift-Tuttle's river of dust, can still slightly perturb the comet particles, just enough to nudge them closer to the Earth. The result is usually an enhanced Perseid display, producing more than the usual complement of meteors.
What do the Perseid pundits say?You can see a map charting that interaction here.
Another noted meteor expert, Mikhail Maslov of Russia, speaks directly of the Jupiter effect and forecasts higher-than-normal Perseid rates — perhaps up to 120 per hour — during the early hours of Aug. 13. He writes, "From 2015 to 2017, the Earth will encounter the perturbed part of Perseid stream, which was shifted closer to the Earth's orbit by Jupiter's gravitation. This means that in these years we have to expect heightened Perseid activity. For 2015, the shift amounts to about 418,000 miles [673,000 km], so in 2015 the Perseids are expected to give higher than usual activity compared to recent years."
You can see more details concerning Maslov's findings here:
You can get lots of valuable details on observing the Perseids from the IMO here:
How to observe the 2015 PerseidsDouble Perseid Fireballs Caught on Camera (Video)]
It is not necessary to continuously stare at the constellation Perseus itself to see the Perseid meteors. A Perseid may appear in any part of the sky, but its trail, if mentally traced backward, invariably leads back to Perseus.
Typically the meteors appear as bright, swift streaks. A few outstandingly bright meteors (fireballs) occasionally may be seen. Fainter meteors appear white or yellow; brighter ones appear green, orange or red. About one-third leave luminous trains, which may be spectacular, and can persist for many seconds; the brightest meteors often end in flares or bursts (called "bolides") and are even capable of casting shadows!
Editor's note: If you snap a great photo of the Perseid meteor shower and want to share it for a possible story or gallery, send images and comments in to managing editor Tariq Malik at .
SPACE.com
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