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Once-in-a-lifetime meteor shower Sunday
![NASA, Schindler Leung in Hong Kong] A Leonid fireball on 16 November 1998](2001-11-14-meteors.jpg) Q: I heard that there is supposed to be a large meteor shower November 18th. Am I going to be able
to see it in South West Manitoba? If so, at what time? MS, Brandon, Manitoba, CA
A: Yes. Everyone in North America can simultaneously see the first peak shower and those in Australia and
east and central Asia can see the second peak, weather permitting, of course. "It's important to watch at the
right time, as the storms are expected to last less than an hour," says Anthony Cook, astronomer at the Griffith
Observatory in Los Angeles.
[NASA, Schindler Leung in Hong Kong] A Leonid fireball on 16 November 1998
Early Sunday morning on the 18th of November, the first burst peaks about 5 a.m EST, 4 a.m. your time
(Central Standard Time, CST), 3 a.m. MST, and 2 a.m. PST. The second one peaks eight hours later
(between 1700 and 1900 UT) in the predawn hours of the 19th of November on the other side of the world,
across the international dateline. See "Second meteor-shower peak" in Further surfing below for Australian
and Asian times.
According to predictions, the meteors could fall at the rate of 70 per minute for a brief time centered around 4
a.m. CST-"making this one of the most intense meteor showers ever and truly a once-in-a-lifetime event," says the Griffith Observatory.
Go to a wilderness location (where you can see the Milky Way clearly) to view great numbers.
A comet that comes by every 33 years causes this spectacle. Nine years before the United States declared its independence, in 1767, the
comet Tempel-Tuttle streaked across our night skies and left a trail of small grain-sized pebbles and dust, eroded off by the solar wind
and radiation. Early Sunday morning on the 18th, Earth will pass through this dusty trail again and the dust will hit our atmosphere going
at about 160,000 miles per hour-almost ten times faster than the International Space Station orbits Earth.
The dust particles collide with air molecules 60 miles high in the sky-where auroras form--and slow down. The grains lose kinetic
energy, which is transformed into heat. Each white, hot grain evaporates and glows. The surrounding air molecules ionize and radiate
light. We see a shooting star whose trail is the glowing-hot gas as it gradually cools down and fades into the night.
The shooting star or meteor may be brighter than all the stars around and even appear to emit sparks. These are called fireballs and
"...can leave ghostly trails in the sky that can shine for up to half an hour," says Cook. See figure.
(Answered by April Holladay, science correspondent, November 14, 2001)
Further Surfing:
Griffith Observatory: Leonid meteors
Jet Propulsion Lab/NASA: Leonids
Asia Pacific Space Centre: Second meteor-shower peak
The Royal Observatory Greenwich: Leonids
NASA: Leonids
Asian Pacific Space Centre: Leonids
Sky & Telescope: Meteors
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