Mearth

Earth mass

Mass

The Earth mass is about 5.9722 × 10²⁴ kilograms. It is a measured quantity, not an exact one, and its precision is limited by the gravitational constant: the product GM⊕ is known to about nine significant figures, while G itself is known to only five, so the mass inherits that.

Watch out: Astronomy generally avoids this problem by working in GM rather than M, which is why orbital mechanics is done with the standard gravitational parameter. Any planetary mass in kilograms is a division by a poorly known G and carries the uncertainty to prove it.

1 Mearth 5.9722000e+24 kg