Why Must We Never Look at the Sun?

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The surface of the Sun is about four times hot as a furnace. The lenses or corner of our eyes act like a burning glass when we look straight at the Sun. The lens could be destroyed for life making us blind. Smoked glasses have been believed to be safe to look at the Sun. But even they are not safe. The Sun may look dimmer through it, but it cannot stop the harmful heat rays passing through it. Watching a solar eclipse with naked eye is very dangerous. To observe the Sun, we can project its image through binoculars or a telescope on to a sheet of white card. This can be viewed together by many people.

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