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nBeforenhumans walked on the moon…
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nWencrashed landed some probes onto the moon (starting with thenU.S.S.R.’s Luna 3 in 1959, and we also bounced a laser beam off ofnthe moon!
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nOnnthis date in 1962, MIT scientists bounced laser light—a series ofnhigh-intensity red flashes—off of the surface of the moon, and thenndetected the reflections back here on Earth. It was the first timenthat a laser beam had crossed space.
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Nowadaysnwe can can aim our lasers at the retroreflectors Apollo astronautsnpositioned on the moon. This is an amazing feat, because thenreflectors are so small compared to the distance crossed, and ofncourse the moon is always in motion, orbiting around the Earth; thenaccuracy of hitting the reflectors is like using a rifle to hit anmoving dime two miles away! By measuring the time it takes thenreflected light to return to Earth, we can measure the distance fromnthe Earth to the moon. n
Nowadaysnwe can can aim our lasers at the retroreflectors Apollo astronautsnpositioned on the moon. This is an amazing feat, because thenreflectors are so small compared to the distance crossed, and ofncourse the moon is always in motion, orbiting around the Earth; thenaccuracy of hitting the reflectors is like using a rifle to hit anmoving dime two miles away! By measuring the time it takes thenreflected light to return to Earth, we can measure the distance fromnthe Earth to the moon. nn
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nAndnwe can measure this very large distance incredibly accurately! It’snlike measuring the distance between Los Angeles and New York to onenhundredth of an inch.
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nWenhave discovered that the moon is spiraling away from the Earth at anrate of 38 millimeters per year. Granted, this isn’t an incrediblynfast retreat—but some scientists say that it is faster thannexpected. n
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Thenvery precise, multiple measurements of the moon’s distance have beennused as evidence that Einstein’s general theory of relativity isncorrect, as the theory predicts the lunar orbit discovered throughnthese measurements. Also, the presence of the reflectors has beennused as evidence that humans actually went to the moon. You wouldn’tnthink anybody would need to build a case that people went to thenmoon—everybody knows about the Apollo program and the moon rocksnand the “one giant leap for mankind,” right?—but some peoplenhave claimed that the moon landings were faked! There was even antelevision show—supposedly non-fiction—that claimed to prove thatnAmerican astronauts never went to the moon. (Let that be proof thatnyou really, really, really can’t believe everything you see on TV—notneven the news or “documentaries.”) Check out this website thatndebunks the bad science in the moon-landing conspiracy theories.
Thenvery precise, multiple measurements of the moon’s distance have beennused as evidence that Einstein’s general theory of relativity isncorrect, as the theory predicts the lunar orbit discovered throughnthese measurements. Also, the presence of the reflectors has beennused as evidence that humans actually went to the moon. You wouldn’tnthink anybody would need to build a case that people went to thenmoon—everybody knows about the Apollo program and the moon rocksnand the “one giant leap for mankind,” right?—but some peoplenhave claimed that the moon landings were faked! There was even antelevision show—supposedly non-fiction—that claimed to prove thatnAmerican astronauts never went to the moon. (Let that be proof thatnyou really, really, really can’t believe everything you see on TV—notneven the news or “documentaries.”) Check out this website thatndebunks the bad science in the moon-landing conspiracy theories. n
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nAlsonon this date:
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nAnniversary of the first American cartoon
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