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Astronomy Calculators

Explore celestial measurements, planetary motion, and astronomical phenomena. Calculate orbital mechanics, stellar brightness, and cosmic distances.

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Guided collections that pair astronomy calculators with related formulas, converters, and practical use cases.

All Astronomy calculators

9 tools, sorted alphabetically

Astronomical Unit (AU) Converter

Convert AU to kilometers, miles, meters, light-minutes, light-years, and parsecs with exact 1 AU values and solar-system examples.

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Distance Modulus Calculator

Calculate astronomical distance modulus, distance in parsecs and light-years, apparent magnitude, or absolute magnitude from stellar brightness measurements.

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Light Year Distance Calculator

Convert between light-years, parsecs, astronomical units, and conventional measures. Calculate vast cosmic distances for astronomy research, space exploration planning, and understanding the scale of the universe.

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Updated

Moon Phase Today: Calculator & Calendar

See today's moon phase, illumination, and lunar age, plus the next full and new moon. Build a moon phase calendar for any month or date.

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Orbital Period Calculator

Calculate orbital period from orbital size and central mass using the standard gravitational formula for astronomy and physics problems.

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Planetary Weight Calculator

Compare your Earth weight with your weight on planets, moons, and other bodies using surface gravity and simple conversion formulas.

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Star Magnitude Calculator

Calculate star magnitude, distance modulus, and brightness ratios. Convert apparent and absolute magnitude for astronomy planning.

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Stellar Temperature Calculator

Estimate stellar temperature from color or spectral class. Compare star temperature, color, and classification for astronomy calculations.

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Telescope Magnification Calculator

Calculate the magnification of telescopes with different eyepieces. Determine optimal magnification for various astronomical targets, exit pupil size, field of view, and maximum usable magnification based on aperture.

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