Kevin,

If I've done the math correctly, the angle of the horizon (assume the

Earth is 4000 miles in radius) is:

arcsin(4000/(4000+h))

where h is your height above sea level in miles. So, if you were 3

miles up (about 15,000 ft) your horizon would be out there at 87.78

degrees or about 2 degrees lower than it would be at sea level (which

would be 90 degrees).

- Bill

Re: Archeological study

Posted by: "KevinDCornwell"

kevindcornwell@... kevindcornwell

Sun Nov 1, 2009 8:47 pm (PST)

Chris - I observe at 9200ft, sometimes at 14,000ft. My horizon is the

pacific ocean. Is there a way for SMP to show me the visual horizon

related to my altitude? Or, is the difference so small that I couldn't

tell the difference anyway. I'm hoping to get maybe 2 more degrees when

I get to 14,000...

Thanks,

Kevin

Kevin Cornwell

observing from Mauna Kea, Hawaii.