[meteorite-list] Meteor Seen In Alaskan Sky
From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Thu Apr 22 10:31:29 2004
Meteor seen in Mat-Su sky
BLUISH FIREBALL: Witnesses say burn lasted six or seven seconds.
By DOUG O'HARRA
Anchorage Daily News
February 27, 2004
A meteor streaked across the skies over the Susitna River Valley
on Tuesday night, producing a bluish fireball seen by people in
Homer and Anchorage, according to the National Weather Service.
Two witnesses reported seeing the burn last for six or seven
seconds about 10:20 p.m., said meteorologist Dave Vonderheide.
"It was unusually bright," he said.
Based on their reports, Vonderheide estimated that the object
entered Earth's atmosphere somewhere over Montana Creek and
moved southwest toward Skwentna before fading from sight.
Most meteors are small rocks or grains from space that hurtle
into the upper atmosphere 50 to 60 miles above the surface at
extraordinary speeds, sometimes more than 100,000 mph.
"Globally on any 24-hour night, there's probably several of
these (large) fireballs because there's a lot of stuff out
there in space," Vonder-heide said. "There's just a lot of
rock out there. ... I see two to three of these a year."
Thousands of meteors burn up over Earth each day, most above
oceans or uninhabited areas or during daylight when they
can't be seen, according to a Web site maintained by the
American Meteor Society.
The color comes from the meteor's composition and velocity
as it heats up and disintegrates. Magnesium generates blue-white
light, and so do meteors that are streaking especially fast.
The superheating of atmospheric gases around the object can
also influence the color.
Tracking down meteors for excited observers is all part of
answering the phone at the local weather service office,
Vonderheide said. "Do you know that the word 'meteorology'
has the word 'meteor' in it? And the Latin 'meteor' means
'something in the air.' "
Received on Fri 27 Feb 2004 11:27:49 AM PST