Question

why does the moon appear to be almost of the same size as the sun?

Answer 1

because moon is more closer then compare to sun

Answer 2

The size of the sun is 695,508 km while, the size of the moon is 1,737 km. We know that there is a vast difference by looking at these numbers. However, we feel that from our point of view both look almost same as Sun is located far, far, far away... as well as it is hot ! It's temperatures are such high that you'll never get anywhere near it...on a whole, it's a hot celestial body located far away from earth. On the other hand, Moon is earth's natural satellite that keeps revolving around earth. When it's day in one place then, it's night in another place. You can never experience Day and Night together in any place ! It's Optical illusion that we imagine that Moon and Sun look the same ! But, they're absolutely not ! That is the reason why humans could go near the Moon but, not anywhere near the sun... but, if you've heard somewhere that anyone had gone near the sun, believe me! It's wrong ;) 
No one has ever said that Sun and Moon are of same size, mass and diameter 'cause they're absolutely not !! They're just common optical illusion which gets you to think so. Don't believe you eyes, believe the science (applies only in this case )...

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