[Prev][Next][Index][Thread]

Re: (meteorobs) Re: Rocket Junk Entry ???




I agree with Tony Beresford and Ed Cannon in thinking it very probable 
that the event was the re-entry of the Proton rocket used to launch a 
trio of Uragan global positioning satellites, members of the GLONASS 
system, a few hours earlier from Baikonur.

Only two element sets have (so far) appeared for this object:
Uragan Proton r                                  160 x 135 km
1 26990U 01053D   01335.99111456  .00678177  77909-5  10000-4 0    15
2 26990  64.8508  16.1658 0018997 343.0783  16.9770 16.47070965    14
Uragan Proton r                                  176 x 106 km
1 26990U 01053D   01336.11317538  .01791896  78820-5  10000-4 0    28
2 26990  64.8961  15.7767 0053422   2.4025   3.3366 16.49346660    33

To the extent that these show the apogee height increasing from 160 to
176 km, these are inconsistent unless the rocket manoeuvred between the
epochs of the elements (at Dec 1 23:47 UTC and Dec 2 02:43 UTC
respectively). In fact, I suspect that there was no manoeuvre and that
the discrepancies are due to SpaceCom's difficulty in linking its fixes
while the object was decaying rapidly due to a very low perigee near
its northbound crossing of the equator.

If we assume that it did decay a little more than one revolution later,
I estimate that the following elset may be near the mark for the 
beginning of that final rev, at a northbound equator crossing over the 
eastern Pacific at 04:09 UTC:
Uragan Proton r                                  139 x 103 km
1 26990U 01053D   01336.17272658 1.05297290  82222+1  36526-3 0 90026
2 26990  64.8948  15.5425 0027486   2.3749 357.6381 16.57002316    49

If so, the following table gives the ground track as it reached and
swept over the American mainland:

  Time (UTC)    Lat     Long
   h  m  s    deg N    deg W

   4 14  0     19.9    109.3
   4 14 30     21.8    108.5
   4 15  0     23.6    107.5
   4 15 30     25.5    106.6
   4 16  0     27.3    105.6
   4 16 30     29.1    104.6
   4 17  0     31.0    103.6
   4 17 30     32.8    102.5
   4 18  0     34.6    101.4
   4 18 30     36.3    100.2
   4 19  0     38.1     98.9
   4 19 30     39.9     97.6
   4 20  0     41.6     96.2

This would have taken it over Lubbock, Texas, shortly before 04:18 UTC
and on NNE-wards over western Oklahoma and Kansas towards Lincoln and
Omaha Nebraska which would have been reached at 04:20 were it still in
orbit.

SpaceCom posted two decay notices for this:
Source   Prediction made    Predicted decay at      Latitude Longitude
                UTC                UTC                  deg      deg

SpaceCom   Dec  2 02:34     Dec  2 04:41 +-3h        50.6 N    20.0 E
SpaceCom   Dec  2 04:46     Dec  2 04:16 +-7m        27.0 N   106.0 W

The latter one is consistent with the decay along the arc predicted
above.


Alan
-- 
Alan Pickup / COSPAR 2707:  55.8968N   3.1989W   +208m   (WGS84 datum)
Edinburgh  / SatEvo & elsets:    http://www.wingardot demon.codot uk/satevo/
Scotland  / Decay Watch: http://www.wingardot demon.codot uk/satevo/dkwatch/
          *

The archive and Web site for our list is at http://www.meteorobs.org
If you are interested in complete links on the 2001 LEONIDS, see:
http://www.meteorobs.org/storms.html
To stop getting email from the 'meteorobs' list, use the Web form at:
http://www.meteorobs.org/subscribe.html

Follow-Ups: References: