A faint, triangular glow visible along the ecliptic before dawn or after sunset, caused by sunlight scattered by interplanetary dust particles in the inner solar system. Best seen from dark locations during certain times of year.
From Greek 'zodiaikos' (relating to the zodiac) and 'light' from Old English 'leoht'. Named because it appears along the zodiacal constellations, the phenomenon was first scientifically described by Giovanni Cassini in the 17th century.
You're seeing the solar system's dust disk edge-on! The zodiacal light reveals the flattened distribution of debris left over from planetary formation, making it one of the few ways to directly observe the structure of our solar system's dust environment with the naked eye.
Complete word intelligence in one call. Free tier — 50 lookups/day.