美国军工企业诺思罗普－格鲁曼公司7月13日宣布，根据与美国空军签订的合同，该公司将建立一个更先进的太空垃圾跟踪系统。
总部设在洛杉矶的诺思罗普－格鲁曼公司在一份声明中说，这个名为“太空护栏”的雷达跟踪系统将耗资3000万美元，其用途是跟踪和观测不断增多的太空垃圾，以及仍在轨道中飞行的小型和微型卫星。
声明说，“太空护栏”将取代1961年建造的美国空军“太空侦察系统”，因为旧的系统已不足以应付大量增加的太空垃圾。
诺思罗普－格鲁曼公司特别项目部主任里奇·戴维斯说，与旧系统相比，新系统将能“更准确和更快速地”发现、跟踪太空垃圾，从而有效预防太空轨道中发生碰撞事件，避免太空垃圾给卫星造成破坏。
据该公司介绍，“太空护栏”的选址工作正在进行，澳大利亚某地已被列为3个候选地之一，其他两个仍在考虑中。
据美国媒体报道，50多年来，人类把近3万个可被跟踪观测的物体送入太空，其中的很多人造飞行器在“退休”后，其整体或残骸被滞留在太空中成为太空垃圾。据不完全统计，近地空间现有直径大于10厘米的碎片9000多个，大于1.2厘米的碎片有数十万个。（高原）
译文:
US is to build an Outer Space Trash Tracking System
US defence industry enterprise Northrop Grumman Corporation announced on the 13th July, the company will build a more advanced outer space trash tracking system in accordance with the agreement signed with the US Air Force.
Northrop Grumman Corporation, headquarted in Los Angeles, said in a statement that, the radar tracking system by the name of “Outer Space Guardrail” will cost US$30 million, and its purpose is to track and observe the continuously increasing outer space trash and the mini and micro satellites that are still flying in the orbit.
The statement said, the “Outer Space Guardrail” will replace the “Outer Space Reconnaissance System” that the US Air Force built in 1961, because the old system is no longer able to cope with the vast amount of increased outer space trash.
Chief of the Extraordinary Item Division of Northrop Grumman Corp, Ricky Davies, said that, as compared to the old system, the new system can discover and track outer space trash “with more accuracy and speed”, thereby effectively preventing collision accidents in the orbit, and avoiding the damage that outer space trash could cause to satellites.
According to the company’s introduction, selection of site for the “Outer Space Guardrail” is currently in progress, and Australia has been listed as one of the three candidate sites, the other two is still under consideration.
US media report that in the past 50 years, mankind have sent up some 30,000 trackable and observable objects into the outer space, among which were many aerocraft whose entire bodies or wreckages remain in the outer space as the outer space trash, after “retiring”. According to incomplete data, there are more than 9,000 pieces of fragments of 10 centimetres diameter in the terrestrial space, and fragments measuring more than 1.2 centimetres in diameter amount to several hundreds of thousands. (Gao Yuan)