美国报废卫星今日将撞击地球 落点尚不确定

正在向地球袭来的美国失控卫星预计将于9月23日下午坠地。英媒报道称，这枚与大巴大小相似的卫星可能坠落于地球任何地方，而人类的预警时间只有20秒。它向地球进行的速度是每秒8公里，预计其碎片将散落于直径为800公里的区域内。

A defunct U.S. satellite is expected to crash down to Earth Friday, with nobody knowing where or when exactly it will hit. This was unavoidable, a Chinese expert said Thursday.

一颗美国报废卫星将会在周五撞击地球，然而却没有知道这枚卫星具体会在哪里着陆。这是难以避免的——中国专家周四表示。

Pang Zhihao, a researcher from the Chinese Research Institute of Space Technology, told Xinhua that the crash could have been avoided had the satellite been put into a higher orbit, or manipulated to drop in the South Pacific when it had abundant fuel. It would pose no threat to Earth if these measures had been taken.

中国空间技术研究院研究员庞之浩在接受新华社记者专访时说，此次卫星撞地球的麻烦本来可以避免。假使在燃料充足时，将卫星引导到不易坠落的更高轨道，或是操控它坠入南太平洋的航天器“坟场”，就不会有今天对地球的威胁了。

The satellite was deactivated in 2005 as it ran out of fuel and was left orbiting Earth like a big piece of space junk.

这颗卫星于2005年由于燃油耗尽报废，并像一大块宇宙垃圾一样被扔在了飞行轨道上。

There are other cases of defunct satellites. The European Space Agency said earlier its observation satellite ERS-2 has run out of fuel and is deorbiting. It would therefore also crash sooner or later.

无独有偶，欧洲航天局早前称，据他们预测，ESR-2卫星已脱离轨道，将来的某一天也会撞上地球。

Pang said all countries which are operating space vehicles should take care of their own spacecrafts so that they won't pose any danger.

庞之浩说所有国家都应该好好处理自己国际发射的航天设备，以免造成危险。

The expert also said that the public need not worry too much.

庞之浩专家说，公众也不必过于担心。

Pang said most spacecrafts will be incinerated upon re-entering Earth's atmosphere, and the debris will mostly likely fall into the ocean or hit an uninhabited area. In addition, a debris tracker is able to give a comparatively accurate prediction where the craft will fall about two hours before it hits Earth, giving residents, if there are any, time to evacuate.

庞之浩说航天器的很大一部分将会在进入大气层时被烧尽，而剩余部分将会落入海洋或者一些无人居住的地区。另外，美国等国家现在已经有能力在碎块坠地前约2小时较准确地预报坠落地点，因此受威胁地区的人员有时间疏散或躲避。