Astronomical Events

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Terms

apogee - the point in the moon's orbit that is furthest from the earth

conjunction - the close gathering of 2 or more objects in the sky.  Often this refers to an object (planet, asteroid or comet) that is close to the sun in the sky. 

inferior conjunction - is when the planet Mercury or Venus is close to the sun in the sky when the planet is in between the earth and sun.

superior conjunction - is when the planet Mercury or Venus is close to the sun in the sky and when the planet is on the opposite side of the solar system from the earth.

elong. - elongation - is the angular distance from the sun

equinox - is when the sun rises directly east and sets directly west and there are 12 hours of daylight and 12 hours of darkness.  It is either the first day of fall or first day of spring.

Occn. - occultation - is when an object  "blocks" or "occults" our view of another object.   This term is often used when the moon blocks the light of a star or planet.

opposition - is when an object is opposite the sun in the sky

perigee - the point in the moon's orbit that is closest to the earth

solstice - is when the shortest day or shortest night occurs.  It is either the first day of winter or first day of summer.

ZHR - Zenith Hourly Rate - is the number of meteors per hour that a single observer would be able to see under ideal conditions (perfectly clear-transparent skies, radiant point over head, with no moon in sky, and no light pollution)

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