生活英语|地球轨道‘清道夫’计划

在人类探索宇宙奥秘的同时，很多的太空垃圾也被丢弃在地球轨道上。这类人造太空物体对宇航员导致了生命风险，同时也容易破坏卫星的运作。一位意大利航天局的研究职员建议发射一系列自动清扫机来清理这类太空垃圾。

After a half century of successes in space, low|Earth orbit has become a very messy place.

More than 17,000 pieces of space junk bigger than a hands breadth are floating around up there; the largest of them weighs nearly ten tonnes.

The debris^{1 poses a growing risk to communication satellites and occasionally manned space missions.}

As time goes on catastrophic collisions become more likely, which would create even more debris.

Marco Castronuovo has a simple plan to solve the problem, starting with the largest, heaviest threats.

Hes proposed sending up a robotic mission that will skip between chunks^{2 of junk, affixing3 a little rocket to each one that will drive them out of orbit.}

The debris would then burn up harmlessly in the atmosphere over an ocean.

Each orbital housekeeper^{4 could clean up five objects a year, and would be sent on a seven|year mission.}

Its a slow but straightforward^{5 solution to a problem that could otherwise leave low|Earth orbit completely unusable.}