Perseid Meteors vs. the Supermoon
 
July 28, 2014:  Every year, sky watchers and summertime campers circle on
their calendars a few key August nights-the 11th, 12th and 13th.  These are
the dates of the annual Perseid meteor shower, which rarely fails to please
those who see it.
 
This year they're adding a note: "supermoon."
 
During the second week of August, the biggest and brightest full Moon of the
year will face off against everyone's favorite meteor shower-and the outcome
could be beautiful.
 
http://youtu.be/JkKzMAzT5fs
 
A new ScienceCast video previews the competition between the supermoon of
August and the 2014 Perseid meteor shower.  Play it
 
The source of the Perseid meteor shower is Comet Swift Tuttle. Every 133 years
the huge comet swings through the inner solar system and leaves behind a trail
of dust and grit. When Earth passes through the debris zone, specks of
comet-stuff hit the atmosphere at 140,000 mph and disintegrate in flashes of
light. These meteors are called Perseids because they fly out of the
constellation Perseus.
 
In a normal year, dark-sky observers typically count more than 100 Perseids
per hour.  But this is no normal year.
 
On August 10, 2014, just as the Perseids are set to peak, the Moon will become
full. Moreover, it will become full just as it reaches the place in its orbit
(perigee) that is closest to Earth.  The perigee full Moon of August 10th
-also known as a supermoon- will be as much as 14% closer and 30% brighter
than other full Moons of the year.
 
"This is bad news for the Perseids," says Bill Cooke of NASA's Meteoroid
Environment Office.  "Lunar glare wipes out the black-velvety backdrop
required to see faint meteors, and sharply reduces counts."
 
But there's good news, too.
 
http://tinyurl.com/o8m67ng
 
Since 2008, the Perseids have produced more fireballs than any other annual
meteor shower. The Geminids are a close second. See the dataThe debris stream
of Comet Swift-Tuttle is broad, and it is possible to see Perseids as early as
late July, well before the Moon becomes full.
 
Also, notes Cooke, "the Perseids are rich in fireballs as bright as Jupiter or
Venus. These will be visible in spite of the glare."
 
Using a network of meteor cameras distributed across the USA, Cooke's team has
been tracking fireball activity since 2008, and they have built up a database
of hundreds of events to analyze. Their data show the Perseids are the
undisputed 'fireball champion' of annual meteor showers.  "We see more
fireballs from Swift-Tuttle than any other parent comet," he says.
 
A warm summer night, a moonlit landscape, and an occasional fireball cutting
past a supermoon: that's an ensemble with a special beauty all its own. Enjoy
the show.
 
Credits:
Author: Dr. Tony Phillips | Production editor: Dr. Tony Phillips | Credit:
Science@NASA
 
Related video:
 
Summer Supermoons -- from Science@NASA
 
 
Regards,
 
Roger

--- D'Bridge 3.99
 * Origin: NCS BBS - Houma, LoUiSiAna (1:3828/7)