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https://theconversation.com/space-debris-will-it-take-a-catastrophe-for-nations-to-take-the-issue-seriously-271141>
"China routinely sends astronauts to and from its space station Tiangong. A
crew capsule is about to undock from the station and return to Earth, but
there’s nothing routine about its journey home.
The Shenzhou-20 capsule will carry no crew, because one of its windows has been
struck by space debris. Astronauts noticed an apparent crack on November 5,
during pre-return checks.
Space journalist Andrew Jones explained how experts on the ground had studied
images of the damage and concluded that a piece of debris smaller than 1mm
(roughly 1/25th of an inch) had penetrated from the outer to inner layers of
the glass.
Simulations and tests confirmed a low probability that the window could fail
during the high-temperature re-entry through Earth’s atmosphere. Although a
worst-case scenario, it was one that officials deemed unacceptable. A rescue
mission – Shenzhou-22 – was launched to bring the astronauts back from the
station.
Experts have been warning about the threat posed by space debris for years. The
ever-growing number of space programmes by states and private entities is now
contributing to an increasingly congested environment in orbit.
The European Space Agency estimates that there are more than 15,100 tonnes of
material in space that has been launched from Earth. There are 1.2 million
debris objects between 1cm and 10cm, and 140 million debris objects between 1mm
and 1cm.
In low orbit they will be travelling around 7.6 km/s (roughly 17,000 miles per
hour), damaging anything they hit. This is how a piece less than 1mm in size
was able to penetrate the thick glass of Shenzhou-20’s capsule.
Given the mounting number of objects in orbit, this is likely to be a more
regular occurrence. It’s costly in terms of damage to equipment, and
increasingly a threat to life. When a piece of debris hits another object in
space, it can also create more space debris, adding to the problem.
A number of countries are able to track what’s in space, but given that these
may include classified satellites, there is a reluctance by states to share
details. China’s space programme is overseen by its military, in line with a
view that space is inherently linked to national security. This only adds to
the geopolitical tensions between states around the use of space."
Cheers,
*** Xanni ***
--
mailto:xanni@xanadu.net Andrew Pam
http://xanadu.com.au/ Chief Scientist, Xanadu
https://glasswings.com.au/ Partner, Glass Wings
https://sericyb.com.au/ Manager, Serious Cybernetics
