The Planet Quiz Show  



Answer:

Mercury and Venus are the only two planets in the solar system for which no moons have been discovered.



[Mercury and Venus are moonless]
Even though Mercury (3,032 miles in diameter) and Venus (7,520 miles in diameter) have no moons, they are in themselves very interesting planets. The yellow markings running across Venus' surface are lava flows from volcanic eruptions. Mercury and Venus are in correct sizes with respect to each other. Mercury, MESSENGER photo; Venus, Magellan photo...

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