Which two planets are notable for not having moons?

The two planets that are notable for not having moons are Mercury and Venus. Mercury, the closest planet to the Sun, has a very thin atmosphere and is not able to capture or maintain any significant satellites due to its small size and proximity to the Sun's gravitational influence. Similarly, Venus, while being the second planet from the Sun, also lacks any natural satellites.

Both Mercury and Venus are terrestrial planets, and their lack of moons sets them apart from many of their planetary neighbors, which often possess one or more natural satellites due to their larger mass and the gravitational pull they exert. In contrast, Earth has one moon, and Saturn has numerous moons, showcasing stark differences between these planets in terms of their satellite systems. Mars does have two small moons, and the gas giants, like Jupiter and Saturn, host many moons of various sizes, making the situation for Mercury and Venus particularly unique.