A tale based on an Arab legend. The stars in the sky ...
A tale based on an Arab legend. The stars in the sky vary in brightness. There can be many reasons for this based on processes going on inside the star or around it. The star in this story is an eclipsing binary star.
Build a realistic model of the Earth using sunlight as a reference ...
Build a realistic model of the Earth using sunlight as a reference to understand phenomena related to the position of the Earth with respect to the Sun.
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