BEIJING (BNO NEWS) -- A debris tracker will be able to provide a two-hour warning should debris from an out-of-control U.S. satellite crash in populated areas, Chinese experts said on Friday.
NASA's Upper Atmosphere Research Satellite (UARS) is expected to re-enter Earth's atmosphere on late Friday afternoon or early Friday evening, almost six years after the end of its productive scientific life. Although the spacecraft will break into pieces during re-entry, not all of it will burn up in the atmosphere.
As of early Friday morning, the orbit of UARS was 110 miles by 115 miles (175 kilometers by 185 kilometers), and re-entry could happen sometime Friday afternoon or early Friday evening U.S. time. While NASA has ruled out an impact in North America, it remains unknown where the debris will fall.
Pang Zhihao, a researcher from the Chinese Research Institute of Space Technology, told China's state-run Xinhua news agency on Friday that the debris will most likely fall into the ocean or an uninhabited area. Nonetheless, a debris tracker will be able to give a fairly accurate prediction where debris will fall about two hours before it hits Earth, giving any residents some time to evacuate.
NASA previously said the risk to public safety or property is extremely small, but a small chance remains that debris could impact a populated area. It is estimated some 26 pieces, the heaviest weighing around 350 pounds (158 kilograms), will survive the re-entry and fall to Earth.
"It is impossible to pinpoint just where in that zone the debris will land, but NASA estimates the debris footprint will be about 500 miles (804 kilometers) long," the agency said earlier. It added that, since the beginning of the Space Age in the late-1950s, there have been no confirmed reports of an injury resulting from re-entering space objects.
One of the reasons as to why it is unknown where the debris will crash is because the satellite can skip and skitter on the Earth's atmosphere. The debris will also roll and rotate as it goes down due to pieces sticking out, making it harder to project a precise course. Space weather such as solar flares can also affect the atmosphere.
Pang also criticized NASA, saying a potential crash in a populated area could have been avoided if the satellite had been put into a higher orbit or manipulated to drop in the ocean after it ran out of fuel.
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