Space calculators

Interactive tools for exploring space and astronomy. More calculators are on the way.

Weight on Other Planets

See what you'd weigh on Mercury, Venus, Mars, Jupiter, Saturn, Uranus, and Neptune.

Light-Time & Distance Calculator

Real light-travel time between planets and stars, plus a custom km/AU/light-year/parsec converter.

Moon Phase Calculator

Real synodic lunar phase for any date, with astrophotography advice and upcoming phase-change projections.

Cosmic AI Explorer

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