An international group of astronauts, scientists and others have called for a rapid expansion of efforts to detect asteroids capable of causing widespread destruction on earth, warning that this is one of the biggest threats to humanity in the coming centuries.
一个由宇航员、科学家等人组成的国际团体呼吁尽快加大侦测力度，找出那些能够对地球造成大面积损害的小行星。该团体警告说，这是未来几百年内人类面临的最大威胁之一。

Led by Lord Rees, Britain’s royal astronomer, and Brian May, a PhD in astrophysics as well as guitarist with the rock band Queen, the group said a hundredfold increase in the number of objects detected each year was necessary over the next decade.
这个团体以英国皇家天文学家里斯勋爵(Lord Rees)和天体物理学哲学博士、皇后乐队(Queen)吉他手布赖恩•梅(Brian May)为首。该团体表示，今后十年，有必要把每年发现的天体数增加一百倍。
Academic projects to detect and track asteroids that might one day collide with earth have been under way for more than 50 years. The work was boosted in 1998 when Nasa was given a decade to identify near-earth objects with a diameter of more than 1km — a size that would turn a collision into a potentially extinction-level event.
发现和追踪可能与地球相撞的小行星的学术课题已开展了逾50年。1998年，美国国家航空航天局(NASA)曾被要求在十年内找出直径大于一公里的近地天体，从而加大了这一工作的执行力度。当天体的直径大于一公里时，与地球的相撞就有可能导致地球上的生物灭绝事件。
However, astrophysicists warn that asteroids and meteors as small as 50m across could still cause devastation on earth, with a direct hit capable of wiping out a city and killing millions. An undetected meteor estimated to be 20m in diameter entered the atmosphere over Russia last year and exploded at a height of several miles, causing a shockwave that injured 1,500 people (pictured). Even the devastating 1908 impact at Tunguska in Siberia, the largest in human recorded history, was caused by an object of only around 50m, said Lord Rees.
不过，天体物理学家警告说，即使是直径只有50米的小行星和流星，仍有可能导致地球上的巨大灾难，因为它的直接撞击能毁灭一个城市并导致数百万人丧生。去年，一个事先未被发现的、直径估计为20米的流星曾进入俄罗斯上空大气层，并在几英里高空爆炸，产生的激波曾导致1500人受伤。里斯勋爵表示，人类历史上有记录的最大规模撞击事件是1908年发生在西伯利亚通古斯的灾难性撞击事件，然而即使是导致那次撞击的天体，直径也只有大约50米。
Only around 1 per cent of the 1m asteroids, meteors and comets that could cause massive damage on earth have been detected so far, according to a declaration by the group issued on Wednesday.
根据该团体周三发布的声明，到目前为止，在可能对地球造成大规模毁坏的1百万小行星、流星和彗星中，人类已发现的只占大约1%。
“Nasa has done a very good job of finding the very largest objects, the ones that would destroy the human race,” said Ed Lu, an astronaut who flew three trips to the International Space Station. “It’s the ones that would destroy a city or hit the economy for a couple of hundred years that are the problem.”
曾三次登上国际空间站(International Space Station)的宇航员卢杰(Ed Lu)表示：“NASA在发现能毁灭人类的极大天体方面取得了很大成绩。现在的问题是那些会毁灭一个城市或导致经济倒退几百年的天体。”
“The more we learn about asteroid impacts, the clearer it becomes that the human race has been living on borrowed time,” said Mr May, who broke off his academic studies to become a musician but returned to complete his PhD at the University of London’s Imperial College in 2007. The campaign launched this week is intended to raise awareness and put pressure on governments to act, he added.
该团体呼吁人们近期将主要精力放在危险天体的侦测工作上，而不要急于找到毁灭或推开危险天体的手段。卢杰表示，处理将与地球相撞的小行星“相对容易”。他说，发现小行星后，距离未来的相撞可能还有几十年的准备时间，“提前这么长时间发现的情况下，人们要做的只是向它们发射飞船而已”。里斯勋爵表示，作为对NASA地基望远镜的补充，要想侦测可能对地球造成毁灭性的打击的小型天体，可能需要在地球和金星之间飞行的飞船上安装红外望远镜。