Re: Iridium 11 flashes/ISIS-1

Eric Vondra (
Thu, 14 May 1998 20:06:18 -0400

Chris Dorreman wrote:

<<On May 12, 21h42 UT, we (Bram + Chris) observed a
magnificent zenith pass of Iridium 11>>

I noticed while observing Iridium 11 last night (0310 UT 14
May 98) that the first flash (the brightest) in the pattern
was red, and the second was blue. This was followed by two
dimmer flashes, and the pattern more or less repeated in
that configuration in a 4.5 second period (Chris may have
timed his more accurately at 5.5).

Additionally, found ISIS-1 (69 009A) to be a nice binocular
flasher with about a 6.5 second period and flashes up to 3rd
magnitude, with a couple of secondary flashes.

Eric Vondra
Wampum, PA USA
40.8538N 80.3292W