Celestial bodies listed in italics are too faint to be seen with the naked eye and require a telescope for proper viewing.
Celestial bodies listed in white on a dark green background are present all year long.
Celestial bodies listed in green or on a light green background are present in the Spring.
(Note: For the sake of readability, celestial bodies which appear in both Spring and Summer are written like this in the table.)
Celestial bodies listed in yellow or on a yellow background are present in the Summer.
Celestial bodies listed in red or on an red background are present in the Fall.
Celestial bodies listed in blue or on a blue background are present in the Winter.
Celestial bodies listed on a colored background (other than dark green) are present for two seasons.

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All credit for the table above goes to Celiviel.