Is inertia and distance combine to keep Earth in orbit around the Sun and the moon in orbit around Earth and how does gravity keep planets in orbit around the Sun?
It is physically impossible for a free macro body to orbit around another moving body in any type of geometrically closed path. Planets are free macrobodies; the central body (sun) is a moving body and circular/elliptical path is a geometrically closed path. Everybody in the universe is in continuous motion. Hence, in reality, no body orbits around another body in circular/elliptical paths. Current beliefs in circular/elliptical orbits are derived from their relative positions and assuming the central body is static in space. See: http://vixra.org/pdf/1311.0018v1.pdf
Yes, inertia and gravity combine to keep Earth in orbit around the sun and the moon in orbit around the Earth. A combination of gravity and inertia keeps the moon in orbit around the Earth. If there were no gravity, inertia would cause the moon to travel in a straight line. Earth is being kept in its orbit around the Sun and the Moon in orbit around Earth by means of gravity and inertia. This is not done through inertia and distance. The two factors inertia and gravity combine to keep Earth in orbit around the sun, and the moon in orbit around Earth. The two factors inertia and gravity combine to keep Earth in orbit around the sun, and the moon in orbit around Earth. However, it is also moving in a straight line due to inertia. The balance of these two forces keeps the earth in a stable orbit around the Sun. If the Earth were to suddenly stop moving, it would fall directly into the Sun. This is because gravity would be the only force acting on it. Inertia and distance combine to keep Earth in orbit around the Sun and the Moon in orbit around Earth. Newton's law of planetary gravitation states that every object in the universe attracts every other object. Gravity decreases to one fourth of its original value if the distance between two objects doubles.Weight, on the other hand, is an effect or consequence of a gravitational field is different for objects of the same mass on the moon and on the earth because of different gravitational fields. As such, the inertia of an object is the same in any gravitational field. To move in a curved path, a planet must have acceleration toward the center of the circle. This is called centripetal acceleration and is supplied by the mutual gravitational attraction between the Sun and the planet and motion in a circular orbit. The type of force that keeps the Earth in orbit around the Sun is gravity. Gravity is the weakest fundamental force in physics yet the mass of the Sun and the Earth generates enough gravity to keep the Earth anchored in its orbit. The Earth has a gravitational force on the Moon, and the Moon has a gravitational pull on the Earth that is equal and opposing. The Moon is kept in orbit around us by the gravity of the Earth. It constantly shifts the Moon's velocity direction. A planet orbits the sun at a constant speed due to gravity and inertia. The force of gravity pulls a planet toward the Sun. Inertia keeps a planet moving in a forward direction.
Your explanation about the Earth's orbit can be valid only if the Sun is static in space. Anyway, you have already mentioned that the earth is a moving body. How can the moon move around the Earth during its orbiting motion? Observe a cyclist trying to move around a running man.