Bright Passes Obs for Rosat and Topex

J. Donald Gardner (fn470@cleveland.Freenet.Edu)
Thu, 16 Oct 1997 12:24:21 -0400 (EDT)

Rosat and Topex seemed unusually bright last evening.  After passing
the Delphinus constellation at 23:53:50 UT Rosat was about a 1.5 Mag.  
Topex, while passing below Vega at 00:27:00 was about a .5 Mag - 
slightly dimmer than Vega.  In both cases the unusual brightness lasted
about 20 seconds.

Recently there has been some discussion that has discounted the solar
panels as a cause for a temporary increase in brightness.  I believe 
solar panels that are used for spacecraft are tailored to capture
light in the UV and higher frequency range for improved efficiency.
Some reflected light in the visible range probably wouldn't 
affect efficency too much.

I don't believe that Rosat or Topex have mirror ar the Iridiums and DMSP
sats have.  Any thoughts as the the cause? 


Don Gardner
Homepage -
76.8419 W, 39.1796 N, 37m ASL