$课文35 太空探索

633. The Moon is likely to become the industrial hub of the Solar System, supplying the rocket fuels fro its ships, easily obtainable from the lunar rocks in the from of liquid oxygen.

月球很可能成为太阳系的工业中心。从月球上的岩石中很容易提炼出液态氧，作为航天飞船的燃料。

634. The reason lies in its gravity.

其原因在于月球的重力。

635. Because the Moon has only an eightieth of the Earth’s mass,

因为月球的重只有地球的1/8，

636. it requires 97 per cent less energy to travel the quarter of a million miles from the Moon to Earth-orbit than the 200 mile-journey from Earth’s surface into orbit!

因此，从月球到地球的25万英里所消耗的能量要比从地球表面进入地球轨道的200英里所耗能量少97%。

637. This may sound fantastic, but it is easily calculated.

这点听起来令人难以置信，但却很容易计算出来。

638. To escape from the Earth in a rocket, one must travel at seven miles per second.

要乘坐一枚火箭飞离地球，火箭的速度要达到每秒7英里，

639. The comparable speed from the Moon is only 1.5 miles per second.

而从月球出发的相应速度史是每秒1.5英里。

640. Because the gravity on the Moon’s surface is only a sixth of Earth’s (remember how easily the Apollo astronauts bounded along),

由于月球表面的重力仅是地球表面的1/6 -- 还记得阿波罗飞船中的宇航员累松地跳跃 --