How Big Is the Moon?

Earth is about four times the size of the Moon

The Moon is a spherical rocky body with a mean equatorial radius of approximately 1,738 kilometers (1,080 miles) and a diameter of roughly 3,476 kilometers (2,160 miles). In terms of mass, the Moon is relatively massive for a natural satellite, with a mass ratio compared to Earth that is larger than that of most other natural satellites to their respective planets. Its size is substantial enough to exert a strong gravitational influence on Earth, affecting tides and even the length of our days; it is even strong enough that the Moon and Earth orbit a common barycenter located between the two bodies’ cores rather than the Moon orbiting Earth’s center.