William B Magnusson (
Mon, 14 Jun 1999 09:49:09 +1000

Hello all,

Perhaps someone can clear up a little mystery that has developed. I have a
small group of friends who regularly look for visible satellites. We all
live in good 'dark-sky' locations and all appreciate the neccessity for
up-to-date orbital elements and an accurate clock. I can see stars down to
magnitude 5 naked eye and down to magnitude 8-9 with my binoculars. I have
an astro-telescope but rarely use that for satellite viewing as the guide
mechanism is far too slow to react.

The mystery concerns the satellite TRMM ... 25063 97074A. None of us can see
it. No matter how hard we look or how careful we are in assembling the data.

The standard magnitude is listed as 3.5 and SatSpy regularly computes this
to give a visual magnitude as bright as magnitude 2 and sometimes even
brighter when the lighting is favourable. Certainly bright enough to see
even in less than ideal situations. We should be seeing it.

I have checked the latest Molczan element sets and TRMM is still listed as a
magnitude 3.5 (visual observation) object. The size is  given as 5 metres
long and 4 metres diameter cylindrical.

Since the elements are being updated regularly I assume it is still there!

Why can't we see it?

Perhaps it's painted matt black! :) Although the 'visual' tag would indicate
that someone has seen it.

This has turned into a real mystery for us and it would be great if someone
could shed some light on it. (Sorry for the pun!).

My best regards to all.

Bill Magnusson, 
Milawa, Australia.