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either of the two times of the year when the sun is at its greatest distance from the celestial equator
either of two times of the year when the sun crosses the plane of the earth's equator and day and night are of equal length
the phase of the moon in which only a curved edge of the moon's side that faced earth is illuminated
when the size of the illuminated portion of the moon is greater than half but not a full moon
occurs when the Moon passes directly between the Sun and Earth and casts a shadow over part of Earth
the blocking of sunlight to the moon that occurs when Earth is directly between the sun and the moon
a nuclear reaction in which nuclei combine to form more massive nuclei with the simultaneous release of energy
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