* All planets have at least a very thin atmosphere. Even Mercury, the closest planet to the sun, has a very faint exosphere, which is a very thin atmosphere.
* Most planets have moons. Many planets have multiple moons. Even Earth has one!
However, there are some celestial bodies that might fit your description:
* Asteroids: Many asteroids are very small and lack the gravity to hold onto an atmosphere or a moon.
* Some dwarf planets: While not technically planets, some dwarf planets, such as Ceres, have very thin atmospheres and might not have any moons.
It's important to remember that our understanding of space is constantly evolving. As we explore more, we might discover new celestial objects that challenge our current understanding.
