NASA's Upper Atmosphere Research Satellite will fall out of orbit soon, with large pieces perhaps reaching Earth's surface, according to NASA's Nick Johnson at a telephone press conference. John Matson reports Look out below! A defunct satellite the size of a school bus is falling back to Earth. NASA's Upper Atmosphere Research Satellite, or UARS, is expected to reenter the atmosphere at the end of September. And pieces of the satellite will probably survive the fiery breakup. "We looked at the hundreds of different components on UARS, and we believe that we know what's going to survive. We just don't know where.” Nick Johnson of NASA's Orbital Debris Program. “And we believe it's going to be 26 different components that will hit the surface of the Earth somewhere, with a total mass a little over 500 kilograms." UARS studied the atmosphere from 1991 to 2005. It's 35 feet long and about 13,000 pounds, which is large by space junk standards. But debris falls from space all the time, and big objects the size of UARS come down about once a year. Since Earth is mostly water and sparsely populated land, chances are UARS won't cause any harm. But “we just will not know precisely where it's going to come down until it's come down." So keep watching the skies. —John Matson

美国国家航空和宇宙航行局发言人尼克约翰逊在一个电话新闻发布会中表示，美国国家航空和宇宙航行局的高层大气研究卫星即将脱离轨道，大片的残余物可能会落到地球表面。地面上要注意了！一个失去功能的卫星，与校车大小接近的残余物将会落到地球上。美国国家航空和宇宙航行局的高层大气研究卫星，简称UARS，预计将于九月末返回大气层。卫星的碎片有可能会在炽烈的摩擦中幸存下来。美国国家航空和宇宙航行局轨道碎片研究组的尼克约翰逊表示：我们自己比对了数百种UARS中的不同组分，并且坚信得知了什么物质将要幸存下来。只是不知道将落在哪里。并且我们认为将要有26中不同的成分将要撞击到地球上的某处，重量总计略高于500千克。

高层大气研究卫星于1991至2005用于研究大气。它的长度为35英尺，重量约13000磅，比太空垃圾的标准值大。但是一直会有碎片从太空落下，并且每年将会有一个大小同UARS接近的大物体落下。由于地球表面大多是水或是人口稀少，UARS有可能不会造成伤害。

但是“直到碎片落下来，我们才能精确的知道碎片将会落到哪里”。所以要观察天空。——约翰沃森报道