The Solar System by Clue

Hint

Answer

This planet has a density lower than water

Boasts the Solar System's tallest known mountain

Has the shortest day of any major planet in the Solar System

Has a number of moons named for Shakespearian characters

Is approximately 4.5 billion years old

Has been demoted to dwarf planet status

Is mutually tide-locked with the above

Returns to Earth's skies approximately every 76 years

Known for its geyser-like jets of icy particles

Moon known for its resemblance to a Star Wars death star

Hint

Answer

Two moons named after the twin Greek gods of fear and panic

Its core comprises approximately 75% of the entire planet

Minor planet discovered in 1986, sometimes described as Earth's second moon

Region extending out from the orbit of Neptune containing a number of known dwarf planets

The hottest planet, with a mean surface temperature of 462 °C

The only known natural satellite to have a dense atmosphere

The only large natural satellite with a retrograde orbit

Has the smoothest surface of any known solid object in the Solar System, suggesting it may have a liquid water ocean

Largest moon in the Solar System

Name of the succesful mission to land a probe on a comet