澳大利亚使用无线电追踪太空垃圾(图)

太空垃圾的问题非常严重，它不仅威胁到卫星和飞船，还可能无预兆地坠向地面。澳大利亚的射电望远镜阵列（MWA）具有极高的灵敏度，通过观察这些空间碎片反射回澳大利亚广播电台的调频信号，射电望远镜阵列甚至可以追踪到直径只有1米的空间碎片。这样就可以听到来自太空的流行音乐了。

MWA阵列是澳大利亚的国家射电天文台的一部分，是澳大利亚和南非共同承担的“平方公里阵列”的前身。MWA共包括2048个独立的天线按照4x4的阵列排列，共有如上图所示的128个阵列组合。

当调频广播的无线电信号进入太空，与太空碎片相遇后，一部分无线电波会被反射回地球，这样，MWA就可以接收到从遥远的太空反射回的信号了。下次收听广播时，别忘了，在澳大利亚，无线电广播正在帮助追踪太空垃圾。

百度新闻与新华网国际频道合作稿件，转载请注明出处。

Australia's Using Pop Radio to Track Space Junk

Space junk is a serious problem: it threatens satellites and spacecraft, and can plummet unpredictably to earth. Australia's Murchison Widefield Array is a high-sensitivity radio telescope that tracks space debris as small as 1 meter across, by observing how the objects reflect FM signals from Australian radio stations. It's listening to pop music from space.

The array, part of western Australia's Murchison Radioastronomy Observatory, was built as a precursor to the proposed Square Kilometre Array being jointly undertaken by Australia and South Africa. As it stands right now, the Murchison Widefield Array consists of 2,048 individual antennas arranged in 128 four-by-four tiles. A single tile is pictured above.

When FM broadcast radio signals traveling out into space encounter debris, some of the radio waves are reflected back toward earth. The Murchison Widefield Array can pick up signals from objects as far as 620 miles away. So the next time you hear Gotye or Keith Urban on the radio, just think — in Australia, they're helping monitor space junk.

(原标题：澳大利亚使用无线电追踪太空垃圾(图))