Light in the Sky map

What is that Light in the Sky? How to identify it? The answer may result from a few quick observations…

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If you live near a city and is moving, then typically is an airplane.

Few stars and satellites are bright enough to be seen over the din of artificial city lights. If you live far from a city, that bright light is likely a planet such as Venus or Mars — the former of which is constrained to appear near the horizon just before dawn or after dusk. Sometimes the low apparent motion of a distant airplane near the horizon makes it hard to tell from a bright planet, but even this can usually be discerned by the plane’s motion over a few minutes. Still unsure? The above chart gives a sometimes-humorous but mostly-accurate assessment. Dedicated sky enthusiasts will likely note — and are encouraged to provide — polite corrections.

source APOD