Mass of the Earth
| Value | 5.9722e24 kg |
| Status | Measured: ± 6.00e+20 kg (0.0001 relative) |
| Source | IAU/IERS Conventions (2010); GM⊕ divided by CODATA 2022 G |
| Categories | Astronomicalsolar-systemearth |
M_earth in every mass unit
| microgram | 5.9722000e+33 μg |
| milligram | 5.9722000e+30 mg |
| gram | 5.9722000e+27 g |
| kilogram | 5.9722000e+24 kg |
| metric tonne | 5.9722000e+21 t |
| ounce | 2.1066316e+26 oz |
| pound | 1.3166447e+25 lb |
| stone | 9.4046052e+23 st |
| US short ton | 6.5832236e+21 ton |
| grain | 9.2165131e+28 gr |
| unified atomic mass unit (dalton) | 3.5965429e+51 u |
Learning zone
Henry Cavendish's 1798 torsion-balance experiment was reported not as a measurement of G but under the title of weighing the Earth: measure the tiny attraction between lead spheres, compare it with the planet's pull on the same masses, and the Earth's density follows. He got 5.48 times water, within one per cent of the modern 5.514 — a stunning result for an apparatus so sensitive he operated it from another room through a telescope.
The situation is unchanged in principle today. Satellite geodesy gives GM⊕ to nine digits, but converting to kilograms still means dividing by G, so Earth's mass is quoted to only five. Roughly a third of that mass is the iron core, and the whole planet is 81.3 times the mass of the Moon.