Scientists including
Dick Pugh and Alex Ruzicka at the Cascadia Meteorite Laboratory (CML) at
Portland State University are sorting through dozens of phone calls and
emails sent in to the laboratory to determine whether the bright meteor
(fireball) seen over a large region of the Pacific Northwest yesterday
(February 19) at around 5:30 AM Pacific Time produced any meteorites and
if so, where they might be found. Based on eyewitness and seismic
data, it appears that the meteor probably did produce meteorites (rocks
on the ground) northeast of Pendleton in Oregon. Eyewitnesses from
Oregon,Washington, British Columbia, Idaho, Montana, and California saw
a fireball moving generally northwest to southeast. This trajectory
is generally consistent with video of the fireball taken from Portland,
Oregon and elsewhere. Sonic booms sufficiently loud to rattle windows
and startle people awake were reported in Hermiston and Pendleton in Oregon;
at these locations the fireball was bright enough to turn night into day
for a few seconds. Less intense sonic booms were reported in Union,
Oregon. At least one and possibly two major break-ups of the meteor
occurred shortly before it hit the ground, producing dozens of tracks with
three major ones apparently corresponding to large pieces of material.
Some eyewitnesses said the natural display reminded them of a “Roman Candle”
firework. Based on the observations, it appears that the meteor experienced
a “terminal airburst”, fragmenting into various pieces that likely would
have dropped meteorites northeast of the Pendleton area. The explosive
airburst was evidently recorded by seismometers of the Pacific Northwest
Seismic Network (PNSW). Preliminary models of the seismic data indicate
an airburst northeast of Pendleton and southeast of Walla Walla, Washington.
Meteorites would likely be found just downrange (to the southeast) of the
airburst location suggested by the seismic network. Reports of the
fireball and of possible meteorites it produced should be sent to the Cascadia
Meteorite Laboratory (503-287-6733 for Dick Pugh; or by email to Alex Ruzicka
at ruzickaa@pdx.edu ). Dick Pugh
will be visiting Hermiston and Pendleton in the first week of March to
give meteorite lectures, and members of the public are welcome to bring
suspected meteorites to those events.
Information provided by Alex Ruzicka, Assistant Professor of Geology, Portland State University