or simply one that had been noted earlier and then lost track of. 哪颗小行星只是以前发现过而后来又消失了的。

　　By this time, too, astrophysics had moved on so much that few astronomers wanted to devote their lives to anything as mundane as rocky planetoids. 而且，到那个时候，天文物理学已经发展到那种程度，很少有天文学家愿意把自己的时间用来研究岩质类星体这类普通的玩意儿。

　　Only a few astronomers, notably Gerard Kuiper, the Dutch-born astronomer for whom the Kuiper belt of comets is named, took any interest in the solar system at all. 只有几个人对太阳系还有点兴趣，其中引人注目的有荷兰出生的天文学家赫拉德·柯伊伯，柯伊伯彗星带就是以他的名字命名的。

　　Thanks to his work at the McDonald Observatory in Texas, 多亏他在得克萨斯州麦克唐纳天文台的工作，

　　followed later by work done by others at the Minor Planet Center in Cincinnati and the Spacewatch project in Arizona, 以及随后别人在俄亥俄州辛辛那提“小行星中心”和在亚利桑那州“太空观测项目”的工作，

　　a long list of lost asteroids was gradually whittled down 一长串失踪的小行星渐渐被清理出来。

　　until by the close of the twentieth century only one known asteroid was unaccounted for—an object called 719 Albert. 到20世纪末，只有一颗已知的小行星──一颗被称之为艾伯特719号的物体──去向不明。

　　Last seen in October 1911, it was finally tracked down in 2000 after being missing for eighty-nine years. 它上一次出现是在1911年10月；2000年，在失踪89年以后，它终于被找到了。

　　So from the point of view of asteroid research the twentieth century was essentially just a long exercise in bookkeeping. 因此，从小行星研究的角度来看，20世纪主要做了大量的统计工作。

　　It is really only in the last few years that astronomers have begun to count and keep an eye on the rest of the asteroid community. 实际上，只是到了最后几年，天文学家才开始计算和监视其他的小行星。

　　As of July 2001, twenty-six thousand asteroids had been named and identified—half in just the previous two years. 2001年7月以来，26000颗小行星得到命名和确认──其中半数都是在之前两年里完成的。

　　With up to a billion to identify, the count obviously has barely begun. 面对多达10亿颗小行星需要确认的任务，统计工作显然才刚刚开始。