1. 小惑星   astronaut   light years   comet   asteroid   Hint Half-n-half Clue   2. 恒星、惑星   planet   star   moon   solar system   Half-n-half Clue   3. 天文学者   solar system   Earth   astronomer   light years   Half-n-half Clue   4. 大気   astronaut   Sun   outer space   atmosphere   Half-n-half Clue   5. 望遠鏡   light years   meteorite   telescope   solar system   Half-n-half Clue   6. 宇宙   outer space   solar system   atmosphere   universe   Half-n-half Clue   7. 彗星   comet   atmosphere   solar system   astronomer   Half-n-half Clue