The most well-known portrait of a woman in the world is over the moon literally. Recently NASA managed to【B1】______an image of t

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问题     The most well-known portrait of a woman in the world is over the moon literally. Recently NASA managed to【B1】______an image of the Mona Lisa directly to a satellite orbiting the lunar body.
    How far did she have to travel? Nearly 240 000 miles, says NASA, shot by laser from the agency’s Goddard Space Flight Center in Greenbelt, Maryland to an【B2】______on NASA’s Lunar Reconnaissance Orbiter(LRO)spacecraft called the Lunar Orbiter Laser Altimeter, or LOLA.
    NASA【B3】______uses lasers to track the LRO’s altitude as it orbits the moon, and back in 2006 we were sending laser pulses between NASA spacecraft and Earth based【B4】______ separated by millions of miles. The wrinkle here: This was apparently the first time we’d managed one-way laser communication at【B5】______distances, says LOLA principal investigator David Smith with MIT.
    To send the famous image of the Mona Lisa into space required flawless digital timing. First, a black and white version of the famous Italian painting was broken into a 152 x 200 pixel grid, with each pixel represented by a number between zero and 4 095 that【B6】______a shade of gray. Those values were then【B7】_____, one at a time, in 4 096 discrete bursts at a rate of about 300 bits per second.
    On the receiving end, LOLA was able to reassemble the precise values based on the arrival times of each pulse, and NASA says it managed to do so without【B8】_____the LRO’s primary job of mapping the moon’s elevation and terrain. Where the earth’s【B9】_____interfered, causing pixel errors, NASA employed the same error-correction code algorithm used with CDs and DVDs to【B10】_____.
【B4】

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答案observatories

解析 根据空格所在位置可知,空格处应填入名词(词组)与and前面的spacecraft并列。结合录音可填入observatories,意为“天文台”。拼写单词时应注意此处为名词的复数形式。
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