填空题
【案例分析题】
For thousands of years comets had been a mystery to 【M1】______
man.They travel across the sky very fast and have a
bright ’tail’of burnt gas.The comet Tempel I has an 【M2】______
orbit far outside the orbit of the furthest planet in our
solar system,Pluto.It has had been there for 4.6billion years,【M3】______
133million kilometres from Earth.Last week
a little American spacecraft crash into Tempel 1.【M4】______
The spacecraft had a camera and it took a photograph
of the comet every minute after it finally crashed into 【M5】______
its surface.The space mission to Tempel 1cost $335
million and was called Deep Impact.Spacecraft was 【M6】______
travelling at 37,000kilometres per hour when it hit the comet
and the crash completely destroying the spacecraft.But before 【M7】______
it hit the comet,the spacecraft took some amazingly photographs.【M8】______
The last one was a close up picture the spacecraft spent 【M9】______
just 3seconds time before it crashed into the comet.【M10】______
【M1】()