Why does the moon's size seem to fluctuate?
Moon orbits Earth in an elliptical orbit.
The moon appears larger than usual during its rise and set, but this is only an optical illusion; if we measure the moon's angular diameter, the size will remain the same. Hence, the distance varies from 362600 km to 405400 km.
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The moon's size seems to fluctuate due to its elliptical orbit around the Earth, causing its distance from Earth to vary throughout its orbit. When the moon is closer to Earth (perigee), it appears larger, and when it's farther away (apogee), it appears smaller. This phenomenon is known as the "moon illusion."
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The apparent fluctuation in the Moon's size, known as the Moon illusion, is primarily due to psychological factors rather than actual changes in the Moon's physical size. When the Moon is near the horizon, it appears larger compared to when it is higher in the sky. This optical illusion occurs because of the way our brains perceive the Moon in relation to familiar objects such as trees, buildings, or mountains on the horizon. As a result, the Moon appears larger when viewed alongside these objects. However, when the Moon is higher in the sky, there are fewer reference points, causing it to appear smaller by comparison. Despite these perceptual changes, the Moon's actual size remains relatively constant throughout its orbit around Earth.
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When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.
When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.
When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.
When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.

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