A European ATV supply ship burns up in the atmosphere over a remote part of the Pacific Ocean.
This re-entry was carefully planned and controlled.
It’s the unpredictable damage that spacedebris could do to orbiting spacecraft
that’s now a major cause for concern.
Space debris can be anything
from the spent upper stage of a rocket and a disused satellite,
to an astronaut glove or fleck of paint.
There are over 129 million objects estimated to be in orbit that are larger than a millimetre.
And even a coin-sized piece of debris
travelling at up to 56 000 kilometres per hour
will rip through a satellite faster than a bullet
with destructive force.
At the moment the most-known encounters are between active satellites and space debris.
An example of a certain event happened in 2009
where we had a collision between an active telecommunications satellite,
Iridium,
with an inactive space debris satellite, Kosmos.
So this collision resulted in thousands fragments
and many of them are still in orbit.
Orbiting fragments can potentially hit other objects,
producing more fragments and more collisions
a dangerous chain reaction known as the Kessler effect.
Suggested technologies for removing space debris
have so far included everything
from harpoons and nets
to robotic arms.
Nothing is off the table.
ESA has also commissioned ClearSpace-1 for 2025
it will be the first mission to actively remove a piece of space junk
in the form of a Vega launch adaptor.
Nobody has ever removed space debris
and it’s a very challenging mission.
So the first stage is proving that it can be done
and that’s what we’re planning to do with the ClearSpace01 mission in ESA.
Then the scientists are unanimous.
What you need to do is to remove the big object from the most populated orbit.
Why?
Because those are the objects which have the higher risk of collision
and which will create a cloud of smaller debris.
More than 6 000 satellites currently orbit Earth.
Around half of these are no longer working
while many of the active satellites are essential for our modern world
be it telecommunications,
weather updates,
the internet
and GPS.
If damaged or destroyed,
the impact on society would be huge.
We know space debris is a global problem
and that calls for global collaboration
and this collaboration is done,
of course,
in scientific areas
but also among agencies.
And one example is the Inter-Agency Debris Coordination Committee,
the IADC,
where they make sure space agencies work together
on defining the appropriate space mitigation technologies,
forecasting the evolution of the environment
and also exchanging data and information.
ESA,
a founding member and one of 13 space agencies on the committee,
is also hosting the upcoming virtual European Conference on Space Debris
from its site in Darmstadt, Germany.
Scientists, engineers and industry
will discuss the best ways to approach the problem
and how to make space more sustainable.
Agencies are currently tracking 28 000 space debris objects
and ESA is also developing laser tracking technology
and AI-supported automated collision avoidance systems
to reduce the number of false alerts for potential collisions.
The aim, however,
is to act now
and tackle space debris
before it’s too late.