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Message: <blockquote data-quote="Binastro" data-source="post: 3610793" data-attributes="member: 111403">Hi Alexis.Post 32.Nice photo.I cannot identify the aircraft because of the longish exposure.With the  position of the 2 contrails I suppose it could be an Airbus A320 type or Boeing 737.So average wingspan 117ft.The aircraft wingspan is then about 1/433 times slant distance, taking moon as 30.5 arcminutes diameter.This gives 50,600 ft slant distance.In south Carolina the Sun's elevation was about 62 degrees I think during totality, but I don't know where the photo was taken.This gives an altitude for aircraft of 44,600ft, which is a bit high.So something needs to be modified here.The aircraft might not be exactly square on, which would decrease the altitude somewhat. But the aircraft seems to be at cruising altitude.If the photo exposure is known one can get an estimate of speed from the aircraft movement in the photo. They normally cruise at about 540 mph at height.From Flight Radar 24 one might be able to identify the actual aircraft.I frequently see aircraft crossing the Sun in my H Alpha scope. Also birds, sometimes perhaps geese with several crossing the Sun at the same time. Also gulls.P.S.Was the exposure 1/30th second?P.P.S.I made a mistake earlier.I remembered the wrong date for the eclipse.The Sun was 31min 41 sec diameter. 1901 arcseconds.The eclipse was 1.03 magnitude  (1.0306 at greatest eclipse).So Moon about 1958 arcseconds diameter or 32.6 arcminutes.This gives about 47,500 ft slant distance.41,900 ft altitude.I suspect the aircraft might be a Boeing 737, but the photo's location would give a better estimate for aircraft size.</blockquote>

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