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Leonids Meteor Shower to Light Sky
By JOSEPH B. VERRENGIA, AP Science Writer
Brew some coffee. Unpack the lawn chairs. Astronomers predict this
year's Leonids meteor display, expected to appear before dawn
Sunday, will be a dazzler worth missing a little sleep.
``It's now or never,'' said Robert Naeye of the Astronomy Society of
the Pacific. ``Astronomers don't think we'll see another storm like this
one until the year 2099. We will probably never see a better meteor
shower in our lifetimes.''
Every year scientists fly to places like the Gobi Desert or Canary Islands
to watch the heavens rain fire for a few minutes in November. This year,
Earth's alignment suggests that North America will be squarely beneath
some of the most vigorous shooting stars. Pacific Islands and the Far
East may see natural fireworks, too.
The most optimistic celestial forecasts call for a steady storm of 4,000
meteors per hour, or about 70 per minute around 5 a.m. EST Sunday.
With clear skies, luck and the bonus of a nearly moonless night, people
in some locations could see twice that.
The Leonids are dust particles shed by Comet Tempel-Tuttle. Like a
truck barreling down a dirt road, the comet trails a cloud of dust as it
orbits the sun once every 33 years.
The meteors are called Leonids because they appear to radiate from the
constellation Leo, the Lion. A really big meteor is equal to a grain of
rice.
Earth usually crosses a thin section of the Leonids trail; perhaps 10
meteors per hour streak across the night sky.
When the comet sweeps close to the sun, the sun's heat causes it to
shed more debris like a truck hitting a mud puddle. Earth gets splattered
when it plows though the thick wake. It occurs every November for a
few years until the particles dissipate.
In 1966, observers couldn't count the shooting stars fast enough.
Estimates ranged as high as 150,000 per hour.
Comet Tempel-Tuttle most recently passed close to the sun in February
1998, and since then, in the words of forecaster Joe Rao, the Leonids
have ``gone berserk.''
While meteor displays thrill amateur stargazers, they also hold scientific
promise. Comets are hurtling balls of ice and debris left over from the
birth of the solar system more than 4 billion years ago.
The particles contain basic elements like iron, as well as carbon-based
molecules. Some scientists believe this is how Earth was seeded with
organic compounds.
``The chemical precursors to life - found in comet dust - may well have
survived a plunge into early Earth's atmosphere,'' said NASA (news -
web sites) scientist Peter Jenniskens, who directs airborne surveys of
the Leonids.
Earthbound viewers are safe during a meteor shower because the tiny
particles tend to burn miles from Earth. In fact, the visible meteor
actually is the streak of light caused by the particle, or meteoroid, that is
generating friction against the atmosphere.
But in space, the tiniest debris behaves like a speeding bullet. Satellite
operators are turning their orbiting equipment edge-on into the storm so
delicate sensors and solar energy arrays will not be crippled by the
barrage.
Predicting the Leonids' vigor has become an annual competition.
Previously educated guesswork meteor predictions are now the
products of sophisticated computer models, enabling scientists to nail
the storm peaks within a few minutes. This year, the Earth will pass
through multiple debris trails shed by the comet as long ago as 1699.
``The comet is almost 4 years behind us now,'' said Rao, who handicaps the Leonids for Sky &
Telescope magazine and the American Museum of Natural History in New York. ``The predictions are
all over the place.''
Tom Van Flandern of Meta Research in Chevy Chase, Md., a non-profit astronomy group, predicts
``no fewer than five streams will pass close to the Earth, so that weak (meteor) storms may persist for
several hours before the predicted strong one arrives.''
How strong? Jenniskens is the most optimistic forecaster. He predicts the Leonids will peak at 4,200
per hour at 5:09 a.m. Sunday over the East Coast, 2:09 a.m. over the West Coast. Others predict a
peak of 1,300 to 2,000 per hour.
Predictions elsewhere vary as widely. One group expects a bigger storm eight hours later over the Far
East; William Cooke of NASA's Marshall Space Flight Center predicts no more than 800 meteors per
hour over the Far East.
With so much uncertainty, most U.S. meteor chasers have decided to stay home this year.
Circumstances following the Sept. 11 terrorist attacks have affected some plans; airspace restrictions
probably will ground Jenniskens' airborne mission.
Naeye is joining an astronomers gathering at the Kitt Peak observatory in southern Arizona, where the
skies should be dark and the weather dry.
``The U.S. will get a pretty good show,'' Naeye said. ``Everything is lining up just right.''
By JOSEPH B. VERRENGIA, AP Science Writer
Brew some coffee. Unpack the lawn chairs. Astronomers predict this
year's Leonids meteor display, expected to appear before dawn
Sunday, will be a dazzler worth missing a little sleep.
``It's now or never,'' said Robert Naeye of the Astronomy Society of
the Pacific. ``Astronomers don't think we'll see another storm like this
one until the year 2099. We will probably never see a better meteor
shower in our lifetimes.''
Every year scientists fly to places like the Gobi Desert or Canary Islands
to watch the heavens rain fire for a few minutes in November. This year,
Earth's alignment suggests that North America will be squarely beneath
some of the most vigorous shooting stars. Pacific Islands and the Far
East may see natural fireworks, too.
The most optimistic celestial forecasts call for a steady storm of 4,000
meteors per hour, or about 70 per minute around 5 a.m. EST Sunday.
With clear skies, luck and the bonus of a nearly moonless night, people
in some locations could see twice that.
The Leonids are dust particles shed by Comet Tempel-Tuttle. Like a
truck barreling down a dirt road, the comet trails a cloud of dust as it
orbits the sun once every 33 years.
The meteors are called Leonids because they appear to radiate from the
constellation Leo, the Lion. A really big meteor is equal to a grain of
rice.
Earth usually crosses a thin section of the Leonids trail; perhaps 10
meteors per hour streak across the night sky.
When the comet sweeps close to the sun, the sun's heat causes it to
shed more debris like a truck hitting a mud puddle. Earth gets splattered
when it plows though the thick wake. It occurs every November for a
few years until the particles dissipate.
In 1966, observers couldn't count the shooting stars fast enough.
Estimates ranged as high as 150,000 per hour.
Comet Tempel-Tuttle most recently passed close to the sun in February
1998, and since then, in the words of forecaster Joe Rao, the Leonids
have ``gone berserk.''
While meteor displays thrill amateur stargazers, they also hold scientific
promise. Comets are hurtling balls of ice and debris left over from the
birth of the solar system more than 4 billion years ago.
The particles contain basic elements like iron, as well as carbon-based
molecules. Some scientists believe this is how Earth was seeded with
organic compounds.
``The chemical precursors to life - found in comet dust - may well have
survived a plunge into early Earth's atmosphere,'' said NASA (news -
web sites) scientist Peter Jenniskens, who directs airborne surveys of
the Leonids.
Earthbound viewers are safe during a meteor shower because the tiny
particles tend to burn miles from Earth. In fact, the visible meteor
actually is the streak of light caused by the particle, or meteoroid, that is
generating friction against the atmosphere.
But in space, the tiniest debris behaves like a speeding bullet. Satellite
operators are turning their orbiting equipment edge-on into the storm so
delicate sensors and solar energy arrays will not be crippled by the
barrage.
Predicting the Leonids' vigor has become an annual competition.
Previously educated guesswork meteor predictions are now the
products of sophisticated computer models, enabling scientists to nail
the storm peaks within a few minutes. This year, the Earth will pass
through multiple debris trails shed by the comet as long ago as 1699.
``The comet is almost 4 years behind us now,'' said Rao, who handicaps the Leonids for Sky &
Telescope magazine and the American Museum of Natural History in New York. ``The predictions are
all over the place.''
Tom Van Flandern of Meta Research in Chevy Chase, Md., a non-profit astronomy group, predicts
``no fewer than five streams will pass close to the Earth, so that weak (meteor) storms may persist for
several hours before the predicted strong one arrives.''
How strong? Jenniskens is the most optimistic forecaster. He predicts the Leonids will peak at 4,200
per hour at 5:09 a.m. Sunday over the East Coast, 2:09 a.m. over the West Coast. Others predict a
peak of 1,300 to 2,000 per hour.
Predictions elsewhere vary as widely. One group expects a bigger storm eight hours later over the Far
East; William Cooke of NASA's Marshall Space Flight Center predicts no more than 800 meteors per
hour over the Far East.
With so much uncertainty, most U.S. meteor chasers have decided to stay home this year.
Circumstances following the Sept. 11 terrorist attacks have affected some plans; airspace restrictions
probably will ground Jenniskens' airborne mission.
Naeye is joining an astronomers gathering at the Kitt Peak observatory in southern Arizona, where the
skies should be dark and the weather dry.
``The U.S. will get a pretty good show,'' Naeye said. ``Everything is lining up just right.''
