Just in time for Easter: A defunct, 9-ton Chinese space station the size of a city bus is expected to return to Earth — hard — in flaming chunks of metallic debris around Sunday, aerospace scientists say.
But exactly when and where Tiangong-1 (Chinese for “heavenly palace”) will hit is anybody’s guess.
Still, the chances of anyone being hit by a hunk of Tiangong are about 1 in 1,000,000,000,000, according to The Aerospace Corp., a California-based research group that monitors all goings-on above Earth via its Center for Orbital and Reentry Debris Studies.
Aerospace has predicted that the spacecraft will burn up as it re-enters the atmosphere “around April 1st, 2018 07:15 UTC plus or minus 20 hours.” Its researchers have identified a band of “probable” re-entry points around the planet that include well-populated areas in California, Oregon, the Midwest, New York and New England.
That band of re-entry points — between 42.7 degrees of latitude north and 42.7 degrees south — also includes China, Africa, southern Europe, Australia and South America. Canada, northern Europe and Russia are safely out of range.
“The overall risk to an individual from re-entering debris is extremely small compared to the other hazards we face. It is estimated to be less than a 1 in 1 trillion chance that a particular person will be injured by falling space debris. By comparison, the risk of being hit by lightning is 1 in 1.4 million, and the risk that someone in the U.S. will be killed in a hurricane is about 1 in six million,” the aerospace authority said in a public advisory.
Meanwhile, the falling space station has become a media star, inspiring dozens of stories from news organizations worldwide — and lots of dramatic prose. Tiangong has been called a “runaway” and a “rogue” that is set to “plummet,” “plunge” and otherwise “crash” its way home in “fiery glory.”
A fitting end for its honorable history, perhaps. China launched the 34-foot-long spacecraft in 2011 as a prototype and a platform for larger products such as the Tiangong-2, which was launched in 2016, and a future permanent space station. For a brief time, Tiangong-1 supported two successful missions that included China’s first female astronauts. Its last crew departed in 2013.
In 2016, supervising engineers lost their telemetry link with Tiangong-1 and informed the United Nations that the craft had “ceased functioning” and eventually would return to the planet on its own terms. Over time, the space station has fallen from its original orbit of 216 miles above Earth to 131 miles this week, traveling at 17,224 mph.
But now comes a warning. Though the odds are slim that Tiangong-1 — or what’s left of it — will land in someone’s backyard, there are genuine hazards to note.
“If by some truly cosmic coincidence you do find a piece of Tiangong-1 in your neighborhood — or if some debris washes up on a shore near you — here’s some advice on your best course of action: Don’t touch it,” said Brandon Specktor, senior writer for LiveScience.com.
“There are two reasons why you should not approach and touch a piece of space debris. The first is it is a health risk,” space historian Robert Z. Pearlman told Live Science, specifically citing hazardous, corrosive and noxious materials from fuel tanks, and the inevitable sharp edges.
And reason No. 2? Space debris souvenirs are essentially illegal.
“According to the Outer Space Treaty of 1967, a country’s spacecraft is their legal property until they say that it’s not their legal property. No matter where it lands — whether it lands in the ocean and sinks to the bottom of the sea, or whether it lands on their own land or some other country’s land — it belongs to that country of origin,” Mr. Pearlman said.
In the meantime, the Inter-Agency Space Debris Coordination Committee — made up of specialists from 13 space agencies including NASA, the European Space Agency and the China National Space Administration — are trying to narrow down the elusive timing and re-entry point, calibrating the estimates according to the Earth’s rotation and other factors.
“Participants will pool their predictions of the time window, as well as their respective tracking data sets obtained from radar and other sources. The aim is to cross-verify, cross-analyze and improve the prediction accuracy for all members,” the interagency panel said in a public advisory.