Name all the planets in our solar system without a moon.

In our solar system's family of planets, only the two innermost worlds travel through space without a single natural satellite. Their moonless status is primarily a consequence of their close proximity to the Sun. The star's immense gravitational pull creates a chaotic and unstable environment, making it incredibly difficult for a smaller body to be captured or to maintain a long-term orbit around either of these planets. Any potential moon would likely be pulled away by the Sun or have its orbit disrupted until it crashed.

While the Sun's gravity is the simplest explanation, some theories suggest a more dramatic history for Venus. It's possible Venus once had a moon, perhaps formed from a giant impact similar to the one that created Earth's moon. However, a second, later impact may have reversed the planet's rotation, causing the moon's orbit to decay over millions of years until it was eventually reabsorbed by the planet. This leaves Mercury and Venus as the only two major planets in a state of solitude, unlike Earth with its one moon, Mars with its two, and the gas giants with their vast collections.