A lunar eclipse can only happen during a(1) new moon.(2) solstice.(3) first quarter moon.(4) full moon.(5) perihelion passage of the Sun.

(4) full moon.

Explanation:

Lunar eclipse can only occur on a full moon night when the sun the earth and the moon are very much in a straight line.

During this period the the light of the sun that incidents on the moon is blocked by the earth and so we have the phases of the moon due to the relative motion of the three bodies which partially enables the light of the sun to reach the moon.

The moon appears orange-red during this time because the light that reaches the moon is after the refraction through the earth's atmosphere from which the other wavelengths have been absorbed by the earth's atmosphere.

Lunar eclipse can only occur at night and hence it can only be observed from about half of the earth.

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