Earth Masses to Kilograms (M⊕ to kg)
1 Earth mass equals 5.9722×10²⁴ kilograms exactly.
How to convert Earth masses to kilograms
To convert Earth masses to kilograms, multiply the number of Earth masses by 5.9722×10²⁴. This factor is exact. To go the other way, multiply kilograms by 1.674424835×10⁻²⁵ (rounded).
kilograms = Earth masses × 5.9722×10²⁴
Example: 10 Earth masses = 5.9722×10²⁵ kilograms.
Approximate value. Standards for the Earth mass varied by place and period, so this converter uses the most commonly cited value. Treat results as estimates, not exact figures.
About these units
Earth Mass (M⊕)
About 5.9722×10²⁴ kg, the mass of the Earth. Used to compare planets.
Earth mass is the mass of our planet taken as a yardstick for others, and the best current estimate is about 5.9722 x 10^24 kg, with an uncertainty near one part in ten thousand. NASA's Earth fact sheet and the International Astronomical Union's recommended value agree with this figure.
No scale can weigh a planet, so the mass is found by dividing the planet's gravitational parameter by Newton's constant G. The parameter itself is known to about two parts in a billion from satellite tracking, but G is known only to roughly two parts in a hundred thousand, so the mass inherits that limit. For this reason astronomers often quote GM or mass ratios instead.
The history begins with Nevil Maskelyne's Schiehallion experiment in Scotland in the 1770s, whose result implied a density about one fifth too low. Henry Cavendish's laboratory torsion balance of 1798 produced a density within about 1 percent of the modern one. Uncertainty fell to about 0.2 percent by the 1890s. About 333,000 Earth masses make one solar mass.
1 Earth mass = 5.9722×10²⁴ kilograms (approximately).
Sources: Wikipedia: Earth mass; NASA Earth Fact Sheet
Kilogram (kg)
The SI base unit of mass. Since 2019 it is defined by fixing the value of the Planck constant, replacing the old platinum-iridium cylinder in Paris.
Oddly for a base unit, the kilogram began life as a derived one. In 1793 revolutionary France defined the grave as the mass of one litre of water, and a decree of 1795 then replaced it with the kilogramme, a name built from the Greek khilioi (a thousand) and gramma, a Late Latin word for a small weight. In 1799 a platinum cylinder, the Kilogramme des Archives, became the physical standard, matching a cubic decimetre of water at its densest, around 4 degrees Celsius. In 1889 the metric community adopted a platinum-iridium cylinder made in 1879, the International Prototype of the Kilogram, nicknamed Le Grand K.
The kilogram is still the only SI base unit with a prefix in its name. Because SI forbids stacked prefixes, a millionth of a kilogram is a milligram rather than a microkilogram, so every mass prefix is attached to the gram. Calibrating every national standard against one object in a vault near Paris meant that all of them drifted relative to it, so in November 2018 member states voted to tie the kilogram to a fixed value of the Planck constant. The change took effect on 20 May 2019. Day to day nothing shifted, but the definition no longer depends on a single piece of metal.
The kilogram is the reference unit for weight & mass on this site.
Sources: NIST: Kilogram introduction (SI redefinition); Wikipedia: Kilogram
Related conversions
- Kilograms to Earth masses (reverse)
- Earth masses to grams
- Earth masses to metric tons
- Earth masses to pounds
- Earth masses to ounces
- Grams to kilograms
- Metric tons to kilograms
- Pounds to kilograms
- Ounces to kilograms
- Milligrams to kilograms
- Micrograms to kilograms
- Carats to kilograms
- Stone to kilograms
- Short tons to kilograms
- Long tons to kilograms
- Troy ounces to kilograms
- Daltons to kilograms
See all weight & mass units.