Re: Jake's unidentified flaring sat

Jake Rees (
Tue, 3 Aug 1999 13:26:45 -0700

Also: Re: Unidentified Bright Flaring Satellite

Yes, Rob, your answer of OAO 1 (#2142) is a very good match.  You passed my
test...... <g>.  Actually, I failed to determine what it was because of
inexperience and/or haste and/or making invalid assumptions.  Lessons were

The one thing I was most sure of was that the satellite had made a near
equilateral triangle with Jupiter and Saturn, the satellite being the most
southeasterly point of that triangle.  I knew that it had faded after that
point and after some seconds had elapsed, it was 5:22-23 AM PDT (12:22-23
UTC).  And it distinctly seemed to have a pace close to that of an Iridium.
Indeed, OAO 1 was at 421 nautical miles altitude and using Iridium 9 as an
example, its altitude shows 421-435 nm. (using STS Plus).  I had determined
with a star software called SkyGlobe that approx. Az. 137, El. 57 would have
formed the triangle with Jupiter and Saturn.  Using STS Plus to play the
pass, OAO 1 was very close to Az. 137, El. 55 (Az.137.07,El.54.55) at
5:21:36 (12:21:36 UTC), close enough for me.

My first mistake in the search was to have the "dimmest satellite magnitude"
in SkyMap set too low.  It was at +4.  At the time of my first search, I did
think of raising the magnitude for the search.  I went to the lighting
constraints menu and saw "F6 - Default satellite standard magnitude".  It
was set for +6 which I thought was high enough.  I may have changed it to 8
anyway; I can't remember.  But in my haste, I didn't see "F5 - Dimmest
satellite magnitude" which is what should have been adjusted.  It was at +4,
I believe.  After Stephen's post, I realized what had happened, so had
SkyMap generate several lists each with a higher magnitude number for
dimmest satellite.  OAO 1 did appear on one of those lists but I simply did
not peruse through it carefully enough.  Indeed, OV2-1/LCS2 D (#01642) was
not only too early, but passed too low in elevation to have made the
triangle.  I think that I also had a notion or assumption that it would not
be necessary to raise the the magnitude too much to catch my mystery
satellite in a search since I had observed it so easily with the naked eye.
I was forgetting that dim satellites with high intrinsic magnitude ratings
can flare to very bright magnitudes.  So the old adages "haste makes waste"
and "dim satellites do brighten on occasion" <g> prove true again!

--  Jake Rees