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Science Specialist Ed Yeates reporting:
The fireball thousands of people in four states saw last night
probably disintegrated before anything reached the earth.
Professional star gazers today called the sighting unusual
because it happened so early in the evening. Science Specialist
Ed Yeates is live with more on the story:
It's daylight now, but last night about 7:30, these skies
were dark and on a Sunday night with moderate temperatures
- a lot of people were outside.
"The first thing I thought was maybe a plane was crashing
or something, I mean, because of the flame. You could see
the flames," said Clinton, Utah resident Bruce Jarvis.
A ball of fire, a tail, bright -- it mimics any textbook description
of previous meteor or fireball sightings. But this one was
unusual because as Hansen Planetarium director Seth Jarvis
says, it occurred at a time early in the evening when the
earth is not moving in a forward direction through the solar
system - as it is after midnight
"The object that entered the atmosphere - this meteor
we saw - bright as it was, would have actually been going
a little bit slower because it was not encountering the earth
head on," Jarvis said.
Most meteors hit the earth's atmosphere at 150,000 miles per
hour or more. The sighting last night was probably traveling
about 100,000 miles per hour.
"Got deeper into the atmosphere. Had more time and more
atmosphere to interact with therefore you got all the ablation
-- the frictional heating -- rubbing something together at
100,000 miles per hour just vaporizes it."
"Keep in mind that what most of you saw last night was
probably not much bigger than this in my hand (baseball).
And at 50 to 60 miles up and the speed it was traveling, it
was very doubtful any part of this fell to the earth,"
Jarvis said.
Four billion meteors hit the earth's atmosphere every day.
We don't see most of them because we're sleeping or clouds
block our view. Jarvis says the debris we really need to worry
about are those the size of a football field.
One that size passed within 75,000 miles of the earth two
months ago. He made this computer rendition of just how close
that was. Right here - that's less than the distance between
the earth and the moon.
"This thing came so close to the earth that you almost
felt like your hair was going to flutter in the breeze as
it went by," Jarvis said.
Had that hit, it would have caused incredible devastation.
So, we're lucky - lucky we see mostly the little ones like
last night.
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