Astronomers sent probes to study a terrestrial planet’s surface composition and search for signs of past water.

During the survey, astronomers identified a new minor planet crossing the orbit of Mars.

The terrestrial planets in our solar system—Mercury, Venus, Earth, and Mars—exhibit a wide variety of geological features.

To restore the antique beam engine, the mechanic carefully repaired the sun and planet gear that translated the piston's reciprocating motion into rotation.

The mechanic inspected the sun and planet gears for wear before reassembling the gearbox.

During the astronomy club meeting, I used the phrase my very easy method just speeds up naming planets as a quirky mnemonic to help everyone memorize the order of the planets.