Five years ago, China launched a space station
prototype into low Earth orbit.
Next year, it comes crashing back down.
The eight and a half ton space station module
is called Tiangong-1,
also known as the Heavenly Palace.
It’s part of China’s strategy to create
a large, modular space station made up of
interlocking parts.
And by most reports, everything was going
as planned until recently.
Back in June of 2016, satellite tracker Thomas
Dorman alerted Space.com that, based on his
observations, China had lost control of Tiangong-1.
He predicted that Chinese authorities would
hold off announcing a problem with the module
until the “last minute.”
Flash forward to September 14, 2016.
That’s when representatives from China’s
space program held a press conference announcing
that the module would reenter Earth’s atmosphere
in the next few months.
While no one admitted that things weren’t
going as planned, there was a lot of ambiguity
in the announcement itself.
Here’s what we do know.
Tiangong-1 was always meant to be a short-term
experiment
with an operational life of about two years.
That means China completed the primary mission
objectives back in 2013.
At that point, the lab went into sleep mode.
China continued to monitor the module.
In March, 2016, China officially decommissioned
the space lab.
At the time, it sounded like China had a plan
to deorbit the module.
But based on Dorman’s observations and other
experts, it looks like something went wrong.
The module seems like it will deorbit but
in an uncontrolled way.
Most of the module will burn up on reentry.
But there are some elements, such as the rocket
engines, that are dense enough to survive
the descent through Earth’s atmosphere.
These pieces could become a localized threat.
They aren’t big enough to cause massive
damage, but one could certainly rip through
the roof of a building or crush a vehicle.
The odds are good that any surviving pieces
would crash into the ocean
or an uninhabited region.
There’s an awful lot of surface area on
Earth that isn’t populated.
But that doesn’t mean we’re definitely
in the clear.
There’s no way to be sure -- even as the
station deorbits, we won’t have enough data
to predict when and where pieces may land
until it’s actually happening.
I guess the moral to this story is that science
is hard
and sometimes it falls out of the sky.
I think it’s only fair to mention that a
deorbit in 2016 or 2017
appeared to be the plan all along.
It just looks like a malfunction has turned
this more into a Skylab situation
and less of a Mir scenario.
It’s time to come back to Earth, which means
it’s also time I remind you to subscribe
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