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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Refraction and the Moon (near horizon)
From: Frank Reed CT
Date: 2005 Aug 27, 00:07 EDT
From: Frank Reed CT
Date: 2005 Aug 27, 00:07 EDT
Frank (another Frank!) wrote: "Each morning I check the amazing photos offered up as APOD and think today's image might interest some of you. Check out http://antwrp.gsfc.nasa.gov/apod/ap050826.html. I recall another similar image was posted recently of the moon which may be located in the APOD archives." Nice photo, and yes, very topical... The caption attributes the irregularities in the Moon's appearance to the "turbulent atmosphere". Well, sort of. The notches and bumps in the Moon's limb are basically symmetric (notice the notches in the limb at 4 and 8 o'clock and the bumps at 10 and 2) and they are caused by relatively stable, non-turbulent patterns in the density profile of the lower atmosphere. Except for the fact that the entire lower atmosphere owes its properties to turbulence (hence the name troposphere), this is not evidence of turbulence --it's evidence of layering. -FER 42.0N 87.7W, or 41.4N 72.1W. www.HistoricalAtlas.com/lunars
