1. tian wen xue [jia]   telescope   astronomer   moon   atmosphere   Hint Half-n-half Clue   2. [zhong;chong] li   universe   gravity   comet   light years   Half-n-half Clue   3. [da;dai] qi   astronomer   atmosphere   satellite   planet   Half-n-half Clue   4. yue liang   outer space   astronaut   astronomer   moon   Half-n-half Clue   5. hui xing   comet   solar system   orbit   outer space   Half-n-half Clue   6. tai yang [xi;ji]   astronaut   asteroid   solar system   universe   Half-n-half Clue   7. wei xing   meteorite   satellite   astronaut   meteor   Half-n-half Clue