Sunny friends, For various reasons, I'm wanting to build a rather different dial. The plan is for a south-facing vertical dial, but I want to design it with a horizontal gnomon.
Waugh states that a vertical south-facing dial has the same hour lines as a horizontal dial at the colatitude. Therefore, to calculate the positions of the hour lines, I used the following formula in Excel: =90-(180/PI())*ATAN((TAN(L8*PI()/180)*SIN(Colatitude*PI()/180))) With L8 being the angle of the sun from noon, calculated by [number of minutes from noon] * (15/60). What needs to be changed to make this work properly with a horizontal gnomon? Keith -- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Col Keith E. Brandt, MD, MPH USAF-NASA Aerospace Medicine Liaison Officer Johnson Space Center, Houston, Texas /[EMAIL PROTECTED]// Goodbye cruel world that was my home- there's cleaner space out here to roam Put my feet up on the moons of Mars- sit back, relax, and count the stars /*This message transmitted with 100% recycled electrons --------------------------------------------------- https://lists.uni-koeln.de/mailman/listinfo/sundial
