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【正文】 t part of the retina, causing damage. ? Eclipse glassesViewing the Sun during partial and annular eclipses (and during total eclipses outside the brief period of totality) requires special eye protection, or indirect viewing methods, if eye damage is to be avoided. The Sun39。s disk is by indirect projection. This can be done by projecting an image of the disk onto a white piece of paper or card using a pair of binoculars (with one of the lenses covered), a telescope, or another piece of cardboard with a small hole in it (about 1 mm diameter), often called a pinhole camera. The projected image of the Sun can then be safely viewed。s disk is obscured, some darkening may be noticeable. If twothirds or more of the sun is obscured, then an effect can be observed by which the daylight appears to be dim, as if the sky were overcast, yet objects still cast sharp shadows. 人 物 素 材 添加您自己的文字 添加您自己的文字 添加您自己的文字 餅 圖 50% 24% 10% 16% 50% 24% 16% 10% AAA DDD BBB CCC 關(guān) 系 圖 A結(jié)點(diǎn) D結(jié)點(diǎn) C結(jié)點(diǎn) B結(jié)點(diǎn) A B C D 關(guān)系
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