Answer: mars

AnswerCrossword Clue
MARSFourth of eight, now
MARSPlace explored in 2004 by Spirit
MARSOpportunity came to it
MARSPhoenix lander's destination
MARS"The War of the Worlds" enemy
MARS"The War of the Worlds" world
MARSViking I destination
MARSOPPORTUNITY'S DESTINATION
MARSBar maker
MARSCommon bar name
MARSFourth planet
MARSGod of war
MARSPlanet between Earth and Jupiter
MARSSon of Juno
MARSOctet member with the shortest name
MARSEarth neighbor
MARSJupiter neighbor
MARSOpening movement of Holst's "The Planets"
MARSViking's landing place
MARS"The War of the Worlds" foe
marsto damage or disfigure
MARSPolar Lander's target
MARSPopular chocolate bar
MARSViking destination
MARSIts year is 687 Earth days long
MARSRed planet
MARSWhat Deimos and Phobos orbit
MARSCelestial body
MARSJupiter's neighbor
MARSPathfinder's destination
MARSWhat Phobos orbits
MARSThe Red Planet
MARSTV sleuth Veronica
MARSTwo-mooned world
MARSWhat Deimos orbits
MARSWhere Vikings landed
MARSVikings' destination
MARSWhere Curiosity went
MARS2013's "Treasure" singer Bruno
MARSIts year lasts 687 days