Why is it difficult to observe the planet Mercury?

Mercury is closest to the Sun. It is one of the inferior planets, that is, its orbit (around the Sun) is smaller than Earth's orbit and hence takes much less time to go around the Sun. Mercury takes 88 days to go around the Sun, as compared to the 365 days the Earth takes. Because of these reasons, Mercury is difficult to see. For one, it is very close to the Sun (due to a small orbit) and is always covered by Sun's glare (when viewed from Earth). The only times when we can actually see this planet, are either early morning or late evening, when Sun's light will not interfere and we can find it near the horizon.  Thus, we need to precisely know, when and where to look for this planet.

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