Re: Pinpoint flashes

Jim Varney (
Tue, 16 Jul 1996 23:32:14 -0700

Jim Cook wrote:

>I plead guilty to being the newcomer Walter Nissen quoted recently asking him
>to suggest a  "TOP 10" list and, being new, I have been very reluctant to
>jump "into the fray" - so this is my first post to SeeSat.


>Since discovering MOS 1, I found it passes over my house in the suburbs of
>Washington DC every night sometime after 10 pm EDT (it rises a little later
>each night), traveling slightly retrograde from south to north.

MOS 1 has a mean motion of 14.0039.  The orbit is nearly "resonant,"
which means it has an integral number of revolutions in 24 hours.  The
result of this is that the satellite has the same groundtrack (and sky
track) every day.
>Inexperience aside, however, I have seen MOS 1 enough times  by now to
>suspect that, while it won't explain all of the pinpoint flashes Larry and
>his wife observed during the 10 minutes he mentions, it may well be
>responsible for one or two of them.

I just observed it, and only being 100 miles or so from the original
observer in Sunnyvale, I can say that the pinpoint flashes were definitely
caused by MOS 1.

I watched it rise out of Scorpio at 0545 UT (2245 PDT) with a reasonably
regular flash pattern (8 periods in 113.76 sec = 14.2 sec period).  Once it
got high in the west the glints started.  They got so bright that
I put my binoculars down and just watched with my eyes.  With each flash
period there was a glint, until it reached the handle area of Ursa Major,
where a bright double glint was seen.

The glints were of very short duration so magnitude estimates are difficult.
Mag 1 or 0 would be my guess.

Like I said earlier, I also saw Cosmos 1900 glint in the west and northwest.
A few days ago I watched USA 81 show what must have been 10 small glints in
a half-second (it looked like an arcing electrical connection), also in the
west.  Notice that all three of these objects are payloads.

Maybe we can start a subset of Walter's top ten list: top ten glinters?

Jim, if you see any other satellites with "weird" behavior, be sure and share
it with us...

 -- Jim

Jim Varney      |  121^ 23' 54" W,  38^ 27' 28" N   |           Sacramento, CA
Member, SeeSat-L|            Elev. 31 ft.           |