Earth Day Meteor Shower
 
April 21, 2015:  On April 22nd, millions of people around the world will
gather together at festivals and other events to celebrate our beautiful blue
planet. It's Earth Day, an occasion to pause, reflect, and talk about how to
sustain a clean, healthy environment on Earth.
 
This year, Earth Day will end with a meteor shower.
 
On April 22-23, Earth will pass through a stream of debris from Comet
Thatcher, source of the annual Lyrid meteor shower.
 
https://www.youtube.com/watch?v=_rNmmHXEdTc&feature=youtu.be
 
A new ScienceCast video explores the mystery of the sun's tiniest flares. Play
it
 
As Earth crosses the debris zone, flakes of comet dust, most no bigger than
grains of sand, strike Earth's atmosphere traveling 49 km/s (110,000 mph) and
disintegrate as streaks of light. Typical Lyrids are about as bright as the
stars of the Big Dipper.
 
As meteor showers go, the Lyrids are relatively mild. Most years in April
there are no more than 10 to 20 Lyrid meteors per hour. But sometimes, when
Earth glides through an unusually dense clump of debris from Comet Thatcher,
the rate increases, resulting in what is known as a meteor outburst. Sky
watchers in 1982, for instance, counted 90 Lyrids per hour. An even more
impressive outburst was documented in 1803 by a journalist in Richmond,
Virginia, who wrote:
 
"Shooting stars [were] observed on Wednesday morning last at Richmond and its
vicinity, in a manner that alarmed many, and astonished every person that
beheld it. From one until three in the morning, those starry meteors seemed to
fall from every point in the heavens, in such numbers as to resemble a shower
of sky rockets..."
 
Another published report from the 19th century lists an observer as having
"counted 167 meteors in about 15 minutes, and could not then number them all."
 
http://tinyurl.com/oyekfy3
 
This skymap shows the Lyrid radiant before local dawn on April 23rd. [expand]
No such outburst is predicted for 2015-but then again, no outbursts were
predicted on those previous occasions either.  If you're up late, take a look.
 
The best time to catch the shower is between about 11 pm on April 22nd and
sunrise on April 23rd, in any timezone  in the northern hemisphere.
 
Observing tips: Dress warmly. Bring a reclining chair, or spread a thick
blanket over a flat spot of ground. Lie down and look up. Meteors can appear
in any part of the sky, although their trails will tend to point back toward
the constellation Lyra, from which the meteors get their name.  The hours
before dawn are best, because that is when Lyra is highest in the sky.
 
Sometimes, bright moonlight can spoil a meteor shower.  That will not be the
case on April 22nd. The Moon is just a slender crescent, and it sets shortly
after sunset, so lunar glare will not interfere with the Lyrids.  If you can,
get away from city lights for the darkest possible sky and the best possible
show.
 
Enjoy Earth Day. And then enjoy Earth Night even more.
 
Credits:
Author: Dr. Tony Phillips | Production editor: Dr. Tony Phillips | Credit:
Science@NASA
 
 
Regards,
 
Roger

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