Why are Stars Invisible in the Daytime?

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We cannot see the stars during the day time, although they are always therein the sky. The bright blue sky hides them from our visibility and when the Sunsets, the blue fades away making the stars visible. This blue is caused by the atmosphere. In space or on the airless moon, the sky is always black and stars can always be seen. Some powerful stars can be seen through telescope during daytime.

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