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A knowledge platform for everything above Earth — astronomy, space, the night sky, celestial events, mythology, and astrology as a clearly separate cultural tradition.

Astronomy is presented as scientific, evidence-based, and sourced. Astrology is presented as cultural, symbolic, and interpretive — never as proven science.

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Asteroids
Triple Systems

Asteroids · 1

Triple Systems

Asteroids with two moons — led by 87 Sylvia, the first triple asteroid system found.

87 Sylvia
A large outer-main-belt asteroid and the first asteroid found to have two moons — Romulus and Remus — making it the first known triple asteroid system.
CategoryMain beltTypeCarbonaceous (C)Diameter253 kmDiscovered1866