The Globe and Mail February 22, 2008
Sky rockets in flight, evening delight
B.C. observers may have been first to see U.S. missile shoot down spy satellite; no debris reported on our territory, Ottawa officials say
By Tu Than Ha
The 30 astronomy buffs who gathered on Wednesday evening outside the observatory in Prince George wanted to see the lunar eclipse, but it was too cloudy.
However, around 7:40 p.m., a clearing opened to the southwest and Denise Stoltz saw what looked like a meteor trail. "What's that?" she asked her boyfriend, Brian Battersby, as the group watched large, bright streaks in the night sky.
"It was unlike any meteor I've ever seen. That made our night," said Mr. Battersby, a veteran sky watcher.
They may have been the first people to spot the falling remains of a failed American spy satellite that had been intentionally shattered by a missile fired from a U.S. Navy warship.
The satellite, known as USA 193, was struck at 247 kilometres over the Pacific Ocean, the Pentagon announced.
At the time of the strike, USA 193 was on a northeasterly path, so its first overland crossing would have been over Canada, said veteran satellite tracker Ted Molczan.
Canadian officials were notified Wednesday that the United States would fire the missile and that there was "a minimal possibility" of debris orbiting over Canada. "To date we have no reports of impacts on Canadian land or water," a spokesperson for Public Safety Minister Stockwell Day said.
The U.S. military said it destroyed USA 193 because the satellite, which was out of control and expected to re-enter the Earth's atmosphere by early March, carried 1,000 pounds of toxic hydrazine fuel.
But there were skeptics, who wondered if the missile firing was a show of military muscle-flexing or a way to test missile-defence systems.
"I just don't think [the hydrazine explanation] stands up. ... I just don't buy it," said Ivan Oelrich, an executive at the Federation of American Scientists.
He noted that the United States produces 36,000,000 pounds of hydrazine yearly, which move across the country in trucks and trains. Also, hydrazine is volatile and would disperse harmlessly should the fuel tank even survive the fiery re-entry, said Dr. Oelrich, a chemist by training.
China, which had its own satellite-killing test last year, criticized Wednesday's strike and urged the United States to release more information.
"China is continuously following closely the possible harm caused by the U.S. action to outer space security and relevant countries," Foreign Ministry spokesman Liu Jian Chao said.
U.S. Defence Secretary Robert Gates told reporters that "we are prepared to share whatever appropriately we can."
At a Pentagon briefing, Marines General James Cartwright said the only elements of U.S. missile-defence systems that were used were the network of land-, sea-, air- and space-based sensors tracking the satellite.
The SM-3 missile that was fired had to have modified guidance software. "It's not something that we would be entering into the service in some standard way," he said.
At the same time, he expressed pride for what the U.S. military achieved. "This was uncharted territory. The technical degree of difficulty was significant here."
He said he was "80, 90 per cent sure" USA 193's fuel tank was hit. The bits of debris are no larger than a football, he said.
While it is common for satellites to fail and re-enter Earth, USA 193's case is unusual because a missile shot it down. "This is a sideshow. The bigger mystery is what its real payload was," said Mr. Molczan.
USA 193 was launched on Dec. 14, 2006, from Vandenberg U.S. Air Force Base in California and failed almost immediately.
Mr. Molczan said amateur satellite trackers noticed that USA 193 was emitting a strong but erratic radio signal for the first days before going silent, suggesting faulty circuitry.
Based on the characteristics of its launcher and its orbit, satellite watchers estimate that USA 193 was the size of a van and geared for ground observations.
With a report from Associated Press
*****
How it was done
The U.S. Navy says it successfully struck a crippled spy satellite with a missile launched from a cruiser yesterday. The operation was meant to minimize damage from falling substances - including toxic hydrazine fuel - but a trail of flaming debris was reported passing over northern Canada.
1 - 10:26 p.m. EST: USS Lake Erie, part of a naval task force northwest of Hawaii, fires a three-stage SM-3 missile at the disabled spy satellite, which is travelling at more than 27,000 km/h.
2 - The missile's "kill vehicle" - a non-explosive device at the tip - hits the satellite. They collide at a combined speed of 35,000 km/h.
247 km: Altitude of impact. Below this altitude, debris can fall to Earth without completely burning up. Above this altitude, debris could orbit for decades, disrupting other satellites.
80-700 km: Thermosphere
50-80 km: Mesophere
20-50 km: Stratosphere
0-20 km: Troposphere
3 - Amateur astronomers in Prince George report debris over northern Canada.
4 - Most of the debris will burn up within 24-48 hours, though a small amount may remain in orbit for up to 40 days.
SOURCE: WWW.ZARYAINFOR. , ANALYTICAL GRAPHICS INC., GLOBALSECURITY. ORG, AP
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