Mm
megameter
Lengthexact by definition
The megametre is one million metres, an exact decimal prefix on the SI base unit. It is the convenient scale for planetary bodies: the Earth's mean radius is 6.371 Mm, its equatorial circumference just over 40 Mm, and the Moon's orbit about 384 Mm across.
Watch out: Almost nobody writes it. Planetary radii are quoted in kilometres in practice, so a figure in megametres will usually need converting before anyone else will read it.
| 1 Mm | 1,000,000 m |
Solvers that use length