1. atmosphère   atmosphere   orbit   planet   comet   Hint Half-n-half Clue   2. terre   galaxy   gravity   Earth   outer space   Half-n-half Clue   3. orbite   orbit   satellite   telescope   planet   Half-n-half Clue   4. système solaire   universe   atmosphere   solar system   star   Half-n-half Clue   5. gravité   astronomer   meteorite   asteroid   gravity   Half-n-half Clue   6. soleil   orbit   galaxy   planet   Sun   Half-n-half Clue   7. télescope   universe   telescope   astronomer   outer space   Half-n-half Clue