Space & Earth Science
Why Do We Have Seasons?
Seasons are not caused by Earth getting closer to or further from the sun. They are caused by Earth's axial tilt, which changes the angle and duration of sunlight at different times of year.
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Earth & Space
Why Do Tides Happen?
Tides happen because the moon's gravity pulls on Earth's oceans unevenly, creating two tidal bulges that coastlines rotate through each day.
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Space
Why Is Earth Round?
Earth is round because gravity pulls matter equally from all directions toward the center, shaping large objects into a sphere over millions of years.
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