NavList:

Norm, you wrote:
"To my delight, not only could I see both but I watched ISS disappear as it went into the Earth's shadow, JUST as it approached the altitude of the Moon. All of a sudden, I saw, in my mind, the Earth, Full Moon, Sun and ISS like I had spun a little mental orrery."

Yeah, awesome, isn't it? Sounds like you got the benefit of a little coincidental timing. But coincidences do make those mental images more inspiring. Have you noticed that our ISS June "marathon" has just about come to an end? You get no more passes for nearly three weeks. Nothing!

In the spirit of NavList and traditional positional astronomy and calculation, here's a little project: if you know that the ISS passes DIRECTLY OVER Oxnard, California this evening, June 25, at 8:45:30 local time, heading southeast (it does), then where will it be 45 minutes later...? And 90 minutes later...? How about 15 hours later?? All you need is a globe, a piece of string, and a protractor to work it out. It's all MacGyver from there (http://en.wikipedia.org/wiki/MacGyver_in_popular_culture). The ground track of the ISS (without Earth rotation) is nearly a great circle. The inclination at the equator is 51.6°. the orbital period is 90 minutes. And the Earth turns at its usual rate. Certain digital tools may save you some time without going straight to the exact orbital predictions. :)

And notice that you can determine your position with great accuracy by observing these passes of bright satellites. Visual observation of satellites is a suprisingly accurate method of visual, non-electronic celestial navigation.

-FER
PS: The ISS actually passes directly over Channel Islands Harbor this evening, June 25, at 8:45:30. Greg?? Camera ready?

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