[meteorite-list] What was the true azimuth of the Russian meteor?

From: Matson, Robert D. <ROBERT.D.MATSON_at_meteoritecentral.com>
Date: Fri, 22 Feb 2013 11:55:09 -0800
Message-ID: <7C640E28081AEE4B952F008D1E913F17070D8CAD_at_0461-its-exmb04.us.saic.com>

Hi Bjorn,

I've been gone on vacation for 5 days so I don't know if your
question below was adequately answered yet, but there is no
discrepancy between the two pictures. As I pointed out last
week in one of my posts, while the trajectory "appears" to be
parallel to the Kazakhstan/Russian border in the Meteosat-9
image, the meteor was NOT travelling parallel to the ground,
so its ground track was definitely oriented more clockwise
than the ~80-degree azimuth of the country border. From
Meteosat 9's perspective, the bolide was very nearly on
the limb, so you are seeing it severely foreshortened. More
importantly, the east end of the contrail (right side) is
at a higher altitude than the west end. As a result, when
you project the 3D track down to the ground, it will actually
start on the Kazakhstan side of the border. --Rob

-----Original Message-----
From: meteorite-list-bounces at meteoritecentral.com [mailto:meteorite-list-bounces at meteoritecentral.com] On Behalf Of Bjorn Sorheim
Sent: Sunday, February 17, 2013 10:52 AM
To: meteorite-list at meteoritecentral.com
Subject: [meteorite-list] What was the true azimuth of the Russian meteor?


List,
There seem to be posted two quite different images to the list about
the compass direction from where the meteor came on Friday 15,
morning (local).
Obviously one of them must be wrong. Surprising if the weather image
is wrong, how did that come about?
Which one is closest to the direction used by Esko to compute the
orbital elements? And which is the true direction?
Would be important to clarify this.
North is up in both images. Chelyabinsk is in the mid top at the lower one,
and near the middle in the top image.
The top image suggest azimuth 80 degree, while the lower about 120 degree.
Here is a link to the two differing directions stitched together:

home.online.no/~bsoerhei/astro/meteor/metlist/twoaz.jpg

Bj?rn S?rheim
Received on Fri 22 Feb 2013 02:55:09 PM PST