OK, this all makes sense. -John
----- Original Message ---- > From: luzius.thuerlemann <[email protected]> > To: [email protected] > Sent: Thu, July 22, 2010 10:58:00 AM > Subject: [skychart-discussion] Re: local horizon creation > > Thank you Robert for this post. The last lines describe my project well. I >tried to measure the time when the moon is just completely above or below the >horizon and then look in the Alt/Az-coordinates for the information I need in >the horizon creation file. Then I'd subtract the radius of the moon - about >15' >- from the moons altitude (probably it's center) to get the horizon altitude >where he just rose above. And it's the other way round to find out the >altitude >of the horizon where he just set - meaning adding the moons radius to the >moons >center altitude to get the horizon 15' above the moon. Of course it's not >that >precise - especially when it's waxing moon and I can't see when he just rises >above or sets below the horizon. But with wanning moon or better full moon it >works. And also it's not that precise because of the changing distances of >the >moon, and because one can only simulate whole altitude degrees instead of >minutes and even seconds. But within the range of whole altitude degrees this >measuring method should really do - I mean, a degree is twice the moons >diameter or four times the moons radius! It really should work.
