Is Chinese space station falling toward Michigan? Chances minuscule
Robert Allen, Detroit Free Press
Michigan State new assistant coaches Chuck Bullough, Paul Haynes and Don Treadwell discuss their transitions back to the Spartans’ staff. Recorded Tuesday, March 27.Chris Solari, Detroit Free Press
A 9.4-ton, Chinese space station is falling to Earth.
And in recent headlines across the web, the odds appear grim for Michigan (spoiler: Don’t worry).
“Chinese satellite filled with corrosive fuel could hit lower Michigan,” reports Fox News.
“Will the free-falling 8.5 ton Chinese space station crash into lower Michigan? Experts say that the state falls among ‘the highest probability,’ ” reports the Daily Mail (United Kingdom).
“Debris from falling Chinese space station could land in southern Michigan,” reports Channel 4 (WDIV-TV).
In fact, the stories all refer to a non-frightening report from Aerospace Corporation about the 34-foot-by-11 foot Tiangong-1, the remains of which might not even be intact once it re-enters Earth’s atmosphere sometime in the next several weeks.
“There is a chance that a small amount of Tiangong-1 debris may survive re-entry and impact the ground,” according to Aerospace.
To illustrate the range of possible crash locations, the Aerospace website illustrates a wide belt, including most of the habitable parts of Earth — that is, every continent but Antarctica. Lower Michigan, along with the same latitude across the U.S., Europe and Asia, is in one of two narrower zones of higher probability.
China's Tiangong-1 is predicted to reenter Earth's atmosphere in early April 2018 ± 1 week. There is a chance that a small amount of Tiangong-1 debris may survive the uncontrolled reentry and impact the ground (depicted in the yellow and green area). https://t.co/DcPhLGKTcq pic.twitter.com/v0vuBxDQ73
— I am Legend (@Grannytologist) February 24, 2018
“When considering the worst-case location (yellow regions of the map), the probability that a specific person (i.e., you) will be struck by Tiangong-1 debris is about 1 million times smaller than the odds of winning the Powerball jackpot,” according to Aerospace.
Aerospace is a government contractor that provides research, development, and advisory services to national-security space programs. The Free Press on Monday sought official government sources to confirm how likely Michigan is to get hit by the debris. NORAD referred a query to U.S. Space Command and U.S. Strategic Command, both of which didn’t immediately respond.
NASA said to ask China. The Chinese embassy in Washington, D.C., and consulate in Chicago didn’t immediately respond.
The space station, China’s first, was launched in September 2011 and offered sleeping accommodations for two astronauts before it began its uncontrolled re-entry, according to Aerospace.
Illustrating how difficult it is to predict where the space station will land, a Massachusetts-based astronomer tweeted that a 1-hour “error in our guessed re-entry time corresponds to (a 17,000-mile) error in the re-entry position,” according to the verified account for Jonathan McDowell at the Harvard-Smithsonian Center for Astrophysics.
As Tiangong descends, confusion remains widespread about what we can predict about its reentry. Remember that a 1 hour error in our guessed reentry time corresponds to an 27000 km (17000 mile) error in the reentry position. And currently our estimate has a 2 week uncertainty
— Jonathan McDowell (@planet4589) March 7, 2018
He tweeted Saturday that the latest predictions indicate the space station landing sometime between late March and early April.
Re-entry is difficult to predict because of such factors as the variation in density of the upper layers of the atmosphere, uncertainties about the orientation of the spacecraft over time and uncertainties of its exact location and speed, according to Aerospace.
The closer it gets, locations most likely to be hit with debris will become clearer, said Matthew Linke, who is planetarium director with the University of Michigan Museum of Natural History Planetarium in Ann Arbor.
“The nice thing, of course, is nothing really big is going to come down,” he said.
If the Chinese spacecraft comes through the atmosphere over Michigan, it may be visible as a bright streak in the sky as it heats up on re-entry.
“We dropped ours on Australia, so we have nothing to complain about,” Linke said, referring to Skylab, a U.S. space station that scattered over the country and Indian Ocean as it arrived on July 11, 1979. “It probably hit a wallaby or something, but not much else.”
The Earth is seen from space. (Photo: Getty Images)
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http://www.freep.com/story/news/local/michigan/2018/03/12/chinese-space-station-michigan/417022002/