月球距离的简史：天文钟出现前的月球经度测定
A (not so) brief history of lunar distances: Lunar longitude determination at sea before the chronometer
摘要：
在中世纪晚期，海上经度测定在商业上越来越重要，这是由于长途商船活动的相应增加。在18世纪末成功开发出精确的航海计时器之前，航海家主要依靠月球来确定时间和经度。自古代以来，月食就被用来确定相对位置，但它们的罕见发生排除了它们作为可靠的路标的常规用途。测量月球距离，使用月球和明亮的参考物体-太阳或一颗或多颗明亮的恒星-在天空中的投影位置成为首选方法。1765年，英国经度委员会批准建立航海年鉴，使它的知名度和重要性大增。无数的“投影仪”也加入了这一潮流，导致了月球星历表的激增。到19世纪中叶，天文钟变得更加便宜和普遍，标志着月球距离法作为海上经度测定方法的结束。
英文摘要：
Longitude determination at sea gained increasing commercial importance in the late Middle Ages, spawned by a commensurate increase in long-distance merchant shipping activity. Prior to the successful development of an accurate marine timepiece in the late-eighteenth century, marine navigators relied predominantly on the Moon for their time and longitude determinations. Lunar eclipses had been used for relative position determinations since Antiquity, but their rare occurrences precludes their routine use as reliable way markers. Measuring lunar distances, using the projected positions on the sky of the Moon and bright reference objects--the Sun or one or more bright stars--became the method of choice. It gained in profile and importance through the British Board of Longitude's endorsement in 1765 of the establishment of a Nautical Almanac. Numerous 'projectors' jumped onto the bandwagon, leading to a proliferation of lunar ephemeris tables. Chronometers became both more affordable and more commonplace by the mid-nineteenth century, signaling the beginning of the end for the lunar distance method as a means to determine one's longitude at sea.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
