69. Earth in Danger

第69课 地球危机
Seeing is believing.
眼见为实，
But seeing a huge rock half the size of Earth smash into Jupiter in July 1996 was incredible.
但目睹一颗有地球一半大的巨大石块在公元一九九六年七月撞向木星却令人无法置信。
Can you imagine what would happen if Earth collided with a huge space rock?
你能够想像地球如果撞上太空中的一颗巨大石块会怎么样吗？
It would be disastrous.
那后果将不堪设想。
In fact, it is thought that a meteor killed the dinosaurs millions of years ago.
事实上，有人认为在数百万年前就是一块陨石造成所有的恐龙灭绝。
A rock like the one that hit Jupiter could split Earth in two.
一颗像撞到木星那样的岩石便可把地球撞成两半。
Doing nothing about it is like waiting for the end of the world.
如果不提出对策就无异于等待地球末日的来临。
So scientists plan to start project to identify all space rocks that could hit Earth.
因此科学家打算展开一项计划来辨识所有可能击中地球的陨石。