In nine minutes, the probe had to reduce its speed from 20,000 km per hour to zero, landing from 125 km above Mars.
在9分钟内，探测器必须将速度从每小时2万公里降至零，从火星上空125公里处着陆。
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In 2007 scientists recorded a godwit flying more than 7, 000 miles (11, 500 kilometers), from Alaska to New Zealand, in nine days at an average speed of about 35 miles an hour (56 kilometers an hour).