A LEGO set focused on astronomy and space should include the following details:

1. Celestial bodies: it should have at least models of the Sun, the center of the Solar System, Mars, Saturn, the Milky Way galaxy, and a moon.

2. Spacecraft design: it should include models of space shuttles, spacecraft, and other space vehicles, such as capsules used to transport humans and robots to space.

3. Various spacecraft: the set should include models of different spacecraft, such as the Voyager, Hubble Space Telescope, Mars Rovers, and others.

4. Smaller details: smaller elements that can be included are stars from the Milky Way, thin lines to represent galaxy strings, asteroids, inner and outer planets, moons, and other celestial bodies.

5. Space-themed characters: the set should also include figures related to space and space sciences, such as Neil Armstrong, characters from "Star Wars" and "Star Trek," and other personalities associated with space and astronomy.