Most of the bright objects are stars. Explain your reasons and methods of analysis. Asteroids are made of rock and metals like iron and nickel. They are part of our Solar System. They reflect sunlight and orbit the Sun, like planets and moons.
Asteroids are much smaller than most moons and planets.
Asteroids change position in our starry sky as they orbit the Sun. Since they are part of our own Solar System, they are closer to us than the background stars. Our Earth also orbits the Sun and rotates on its axis. All these motions combine to shift the positions of the asteroids in these images. The stars in these images look bright and small.