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Moons of our Solar System
Moons of our Solar System

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2.3 Orbital inclination

Prograde moons typically orbit their primary planet close to the planet’s equatorial plane. That’s true of the Moon’s orbit too, but it is more useful to relate the Moon’s orbit to the plane of the Earth’s orbit round the Sun, which is called the ecliptic plane. The Moon’s orbital plane is inclined about 5° away from the ecliptic plane.

The orbital planes of the Earth and Moon are at an angle of 5 degrees (written 5°) to one another.
Figure 28 The orbital planes of the Earth and Moon are at an angle of 5 degrees (written 5°) to one another. The angle as drawn is exaggerated for clarity