昨晚拍攝月球拍到一些不知名的東東,是太空垃圾? 小行星還是甚麼,大家看看
0:13開始
https://www.dropbox.com/s/o7boeiyrw2z8d ... 8.avi?dl=0
這是甚麼東東
look like a bird
assume a bird/bat fly 50km/h = 13.89m/s
assume dot(bird) across the moon ~1s (for easy calculation, without checking frame by frame )
moon angular diameter ~ 0.5 deg
distance of bird ~ (13.89/2)/tan(0.25deg) = 27.2m
assume bird's size ~ 0.15m , when 0.15/13.89, only 1% of moon diameter
seems reasonable
of coz, you may try to sub other number in assumption to model the observation.
assume a bird/bat fly 50km/h = 13.89m/s
assume dot(bird) across the moon ~1s (for easy calculation, without checking frame by frame )
moon angular diameter ~ 0.5 deg
distance of bird ~ (13.89/2)/tan(0.25deg) = 27.2m
assume bird's size ~ 0.15m , when 0.15/13.89, only 1% of moon diameter
seems reasonable
of coz, you may try to sub other number in assumption to model the observation.
誰在線上
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