Re: Possible new bright GEO flasher

Mike McCants (mikem@fc.net)
Sat, 7 Mar 1998 00:00:38 -0600 (CST)

Ron Lee wrote:

>This came off of sci. astro. amateur (another reason to have 
>the visual newsgroup).  I made a possible ID as 96039B (#23944),
>CZ-3 Rkt.  Bill Gray (Guide fame)  believes it may be 94056A.

I have one obs of 96 39B in my database (14 months ago) and
my record says tumbling with a period of 32 seconds.  Since
it is a rocket, it would only get to about mag 10 at a range
of 21000 miles.

31.51 110.26 Arizona  Epoch 1998

  ***  98 Mar  4   Wed morning  *** Times are UT ***

23944 CZ-3 Rk        96 39B    14 M 2.5 ELDY  1 M2   55
  MAG    HGT ALT AZI  HRS MIN     R  A    DEC  RANGE
 10.8  20266  36 161   10  40   15 11.5 -20.6  21696
 10.8  19962  36 162   10  45   15 14.2 -20.4  21371
 10.8  19648  37 162   10  50   15 17.0 -20.1  21035
 10.7  19323  37 163   10  55   15 19.9 -19.9  20689

Jeff Medkeff's observation:

>Time: 3:52am March 4 MST (10:52 March 4 UT)
>Position of the satellite J1998:
>15h 12m -19d 47m

The time of passage near Iota Librae for 96 39B would have been
about 10:40:30 and it would have been over 1/2 degree south
of that star.  The motion is 1 degree west in 10 minutes
and that also does not match.

Here is some of Bill Gray's post:

>lot of them,  you wind up with a thick "traffic jam" at about -4
>declination, with only a few inclined enough to get as far south as
>-19.)  But using the geosynch database didn't turn up anything.

Yes, a geosynch that once had an inclination of 0 degrees would have
to be very old to be perturbed to a large enough inclination to
be seen at -19.  But this is not impossible and if it really was
at the southernmost point of its cycle, it would stay at that
declination for a while.

Bill Gray:

>So I switched to a larger "all-satellite" database, and found object
>94056A just a hair to the north of the coordinates you gave.

The elset in tonight's alldat.tle gives:

  ***  98 Mar  4   Wed morning  *** Times are UT ***

23230   ETS-6   94056A         70 M 3.5 ELDY  4 M2   -1
  MAG    HGT ALT AZI  HRS MIN     R  A    DEC  RANGE
 12.0  22511  40 163   10  50   15  9.8 -17.1  23753
 12.0  22375  40 164   10  55   15 13.3 -17.3  23622
 12.0  22234  40 164   11   0   15 16.8 -17.5  23485

Jeff Medkeff's observation:

>Time: 3:52am March 4 MST (10:52 March 4 UT)
>Position of the satellite J1998:
>15h 12m -19d 47m

So the passage of ETS-6 near Iota Librae would have been
about 10:54UT, but it would have been over 2 degrees north
of that star.  ETS-6 has an RCS of 70, so I suppose that
it cannot be ruled out.  But I would assume that Jeff's position
would have been much closer.  Also it is moving about
0.8 degree west in 10 minutes and that does not match Jeff's
observation that it was almost stationary for 10 minutes.

Here is Jay Respler's obs in PPAS7:
94- 56 A 97-09-07 08:11      JHR  65   0.5   5 13.0   mag 8-12.  az132 el 34

Here are Russell Eberst's obs in PPAS7:
94- 56 A 97-12-27 05:16:41.2 RE                50  mag 4.5 to 9.7 flashing
94- 56 A 98-01-02 04:53:31.5 RE                25  mag 6.4 to 9.9 flashing

Jeff Medkeff's observation:

>What I am pretty sure I was seeing is a geosynchronous
>satellite. It stayed *almost* stationary over 10 minutes of
>observing it; the stars drifted right past it, and the
>residual movement in altitude and azimuth was not more than
>a quarter degree over the period I watched. 

The motion of both of the above objects was greater than
1/4 degree in 10 minutes.

>This whole [flash] morphology seems quite unusual to me.

I believe that it matches some of the other geosynch flashers
quite well.

>I would be very grateful if a satellite expert could comment
>on this and give me an idea of what I was watching. I am
>extremely interested to know about this unusual observation,
>which really has me quite baffled and intrigued!

I would assume it really is a geosynch flasher.  And since it's
not in the database, it's a classified object.  And since the
inclination is very large, it's very old.

Depending on its orbital period, it should show up in the
same place at about the same time for several weeks.

Here is an elset that matches Jeff's observation:

Unknown       
1 98063U          98 63.45182900  .00000000  00000-0  00000+0 0    02
2 98063  13.0700 316.0000 0010000    .0000 270.0000  1.00271979    00

But of course the mean motion, eccentricity, and inclination are
all quite uncertain.  If it really is a geosynch, it might be within
a few degrees of this elset for the next few days.

Dan Laszlo's post:

Subject: UnID flashing object seen for 20 min over Pacific

The pilot named Jim wrote:

>I am a corporate pilot. The other night I was returning from a trip through
>the Far East and observed a very interesting object. In the sky to the
>southeast, I saw a blinking light with a period of about 20 seconds. Keep in

This obs was about 1 1/2 hours after Jeff's.  A prediction from
the above elset gives:

     18.478 165.547   41000.      Pacific Ocean 

  ***  98 Mar  4   Wed morning  *** Times are UT ***

98063 Unknown                     M 3.5 ELDY  0 M2    0
  MAG    HGT ALT AZI  HRS MIN     R  A    DEC  RANGE
 14.4  22215   9 108   13  20   18  8.9 -13.6  25278
 14.4  22215   9 107   13  25   18 13.9 -13.4  25274
 14.4  22214   9 107   13  30   18 19.0 -13.3  25269

A prediction for ETS-6 gives:

23230 94056A  ETS-6               M 3.5 ELDY  4 M2   -1
  MAG    HGT ALT AZI  HRS MIN     R  A    DEC  RANGE
 14.2  15765   7 113   13  20   18  8.1 -18.8  18845
 14.4  15441   7 112   13  25   18 15.7 -18.9  18555
 14.7  15110   6 112   13  30   18 23.7 -19.0  18262

So an altitude of 10 degrees could fit either prediction.

>my best guess of the celestial position would put the object above
>Sagittarius and to the right of Scutum, in the vicinity of M24. 

The Unknown position would be a few degrees above Scutum (which would
have been too low to see easily) and about 5 degrees to the left of M24.

The ETS-6 position is very nearly on M24.

So it seems very likely that they saw the same object and there is
a chance that it was ETS-6.  But it could be a 20-year-old
classified geosynch.

Randy Johns posted:

Subject: Unidentified geosynch flasher (ancient)

>About three years ago I was able to see a 2nd
>magnitude goesynch flasher every evening for about two
>weeks near the summer solstice in the evening hours until
>about 10 PM (local).  The period was exactly 120 seconds.
>One evening I pegged it at about longitude 103.5 West.
>I've looked for it the last two summers without success.

The object Jeff Medkeff saw is near longitude 100 west.
A drift of a few degrees in 3 years would be quite reasonable.

Mike McCants