Final answer:
The Moon has a diameter of 3476 kilometers, about a quarter of Earth's, and is roughly 384,000 kilometers away from Earth. In a scaled model, Earth is like a grape and the Moon is a pea over a foot away, fitting into a backpack. Both the Sun and Moon appear similarly sized in the sky from Earth.
Step-by-step explanation:
The Moon's diameter is approximately 3476 kilometers, which is about one fourth the size of the Earth. On average, the Moon is situated roughly 384,000 kilometers away from Earth, which is about 30 Earth's diameters. If we were to imagine a scale model of our celestial neighborhood, where we reduced every dimension by a factor of one billion, Earth would be the size of a grape (approximately 1.3 centimeters in diameter), while the Moon would be a tiny pea, orbiting at a distance of 40 centimeters, just over a foot away. This scaled-down Earth-Moon system could comfortably fit inside a standard backpack, providing a tangible representation of their proportions and distances relative to each other.
It is an interesting coincidence that, from our perspective on Earth, the Sun and Moon appear to be roughly the same size in the sky. This is because although the Sun's diameter is about 400 times greater than that of the Moon, it is also approximately 400 times farther from Earth. Consequently, both have an angular size of about 1/2 degree, leading to phenomena like solar eclipses, where the Moon can completely cover the Sun.