地球的力量 第5集 稀有行星(14):生命存在的關鍵因素

It gave Earth a magnetic shield against thedangerous solar wind.

它給地球一個磁場來抵抗危險的太陽風

And it left us the Moon that provides climaticstability.

還留下了一個月球來確保氣候的穩(wěn)定

If the collision had never happened,Earth may never have been a home to complex life.

如果沒有這次撞擊 地球永遠不會成為復雜生命的家

We've seen the extraordinary consequences of just one chance event on the Earth's destiny.

我們看到地球命運一次意外 就帶給我們多么不尋常的結果

But there's another chance factor that was just as vital,its location.

但是還有一個因素也很重要 它的位置

It's only when you consider our planet's position in the solar system

只有思考一下我們的星球在太陽系中的位置

that you really begin to understand how fortunate it's been.

你才真的意識到我們多么幸運

Too far from the Sun, like Mars, and it's simply too cold for life.

如果離太陽太遠，像火星那就會太冷，不適宜生命生長

A little closer and things improve.This is where you find the Earth.

離太陽稍微近一點就好了 你會發(fā)現(xiàn)地球在這里

We are lucky enough to be in the only place

我們很幸運占據這個太陽系唯一的位置

in the solar system, to our knowledge, that's the right temperature for water,

這里的溫度適合水存在

the most essential ingredient for life to exist on the surface.

水是生命存在的最關鍵因素