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　　Massive machines require engineering extremes.　　The massive man-made satellite, commonly known as the International Space Station, hurtling around the Earth at 27,600 km an hour, has been a temporary home for humans for the last 20 years. The biggest land vehicle on earth, a bucket excavator titled Bagger 293, that can move 240,000 cubic meters of dirt each day. Innovation has always meant building bigger, faster, taller, longer and stronger than anything that came before. We’ve seen them in d