Space mass converter
Convert between solar masses, Earth masses and Jupiter masses, the units astronomers weigh worlds and stars in.
That's about the same as the Sun. That is about 1.988×10³⁰ kg.
What it means
How heavy is that?
The solar mass is 1.98847×10³⁰ kg. Masses of distant objects are inferred from orbits, so they carry real uncertainty.
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Learn
Three things worth knowing
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The Sun is 333,000 Earths
And Jupiter is 318 Earths, which is still only a thousandth of the Sun. The Sun holds 99.86% of everything in the solar system.
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Weighing by orbit
Nobody puts a star on a scale. Mass comes from watching how fast something orbits it, through Kepler’s third law.
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Mass is not size
Betelgeuse is 700 times the Sun’s radius but only 16 solar masses. A red giant is mostly very thin gas.
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Background
About astronomical masses
Kilograms are hopeless at this scale, so astronomers use the solar mass for stars, the Jupiter mass for giant planets and the Earth mass for rocky ones.