[meteorite-list] Boom 28 secs after Russian meteor passes overhead - oops^8 88 secs!

From: Rob Matson <mojave_meteorites_at_meteoritecentral.com>
Date: Sat, 16 Feb 2013 22:32:45 -0800
Message-ID: <000001ce0cd8$98d30ac0$ca792040$_at_cox.net>

Hi Robin,

Okay -- a minute and 28 seconds is quite a bit more "normal".
Now we're talking about an altitude between 25 and 30 km.
With this higher altitude, the average temperature drops so
the average speed of sound will also. Call it around 305 m/sec.
That puts the range at just under 27 km, so altitude might
have been as low as 26 km at closest approach to Korkino.
At that altitude, a large mass might continue more than
100 km further downrange if the entry angle was as shallow
as 10 degrees.

--Rob

-----Original Message-----
From: meteorite-list-bounces at meteoritecentral.com on behalf of Robin Whittle
Sent: Sat 2/16/2013 8:54 PM
To: 'METEORITE LIST'
Cc: Rob Matson
Subject: Re: [meteorite-list] Boom 28 secs after Russian meteor passes overhead
- oops 98 secs!
 
A list member kindly pointed out that there was more than a few seconds
deleted from this video. I didn't look at the minutes figure.

The meteor is overhead at 43:06 and the shockwave arrives at 44.34.

So this puts the altitude about three times the 8.7km estimated by Bob
Matson. From:


http://en.wikipedia.org/wiki/Speed_of_sound#Altitude_variation_and_implications_
for_atmospheric_acoustics

  http://en.wikipedia.org
/wiki/File:Comparison_US_standard_atmosphere_1962.svg

the speed of sound varies somewhat. Since this is a large positive
pressure wave, maybe it would travel somewhat faster than a small
pressure wave at these higher altitudes. Sticking with the 310
metre/sec guesstimate of Bob Matson, 98 seconds gives us 30.4 km.

  - Robin
Received on Sun 17 Feb 2013 01:32:45 AM PST