Re: [guide-user] Geoname files/trail starting times

Bernd Brinkmann Sep 13, 2002

Hello Bill,

> About starting planet/satellite/asteroid trails at "standard" times,
> such as midnight UT or local midnight: I did want to keep the
> flexibility in this, so that people who regularly observe around 20:00
> in the evening could get ephemerides and trails for that time.

Thanks for this, because I use it very often for comet and asteroid
work.

> In reference to this: At some point, I want to add the concept of
> a
> "solar altitude day": instead of advancing exactly one day, Guide
> would advance to the time on the next day where the sun is at the same
> altitude. Thus, if you were showing an evening sky with the sun at
> altitude -9 degrees, you could advance by one "solar altitude day"
> (SAD?) to the time on the next evening when the sun was at the same
> altitude. This would apply for animation, trails, and ephemerides.

This would be a real great thing. I've dreamed of such a function but
never asked for it. Especially for planning of comet observations it
would be nice to see how the object moves nearer to the sun or farther
away.

Clear skies
Bernd

Bernd Brinkmann
Herne, Germany

http://homepage.ruhr-uni-bochum.de/Bernd.A.Brinkmann/index.html