First Space Garbage Truck will be Swiss
The world’s first space ‘garbage truck’ will be Swiss
It is the
first time the European Space Agency (ESA) has allocated such a large sum (€86
million) to a start-up. It's Swiss and its mission is to clean up space debris.
February
10, 2009, 4.56pm GMT: The American commercial satellite Iridium 33 collides
with the Russian military satellite Kosmos 2251 at a speed of almost 42,000
km/h. The two spacecraft disintegrate into more than 600 pieces of scrap metal,
which scatter at 20 times the speed of a rifle bullet.
This is the
first recorded accident of this kind, but by no means the only one. Some of
them are even intentional: the Russians, the Americans, the Chinese and the
Indians have all destroyed one or more of their own satellites to test space
missiles. And these explosions have created thousands of additional pieces of
debris that could damage any orbiting spacecraft – including the International
Space Station. This is the scenario screenwriter and film director Alfonso
Cuarón depicted at the beginning of his film Gravity.
An idea was born
Back in
2009, Muriel Richard-Noca and her students at the Swiss Federal Institute of
Technology Lausanne (EPFL) were celebrating the launch of the SwissCube mini
satellite, which they built together. And while the first 100% Swiss-made space
orbiter is no bigger than a carton of milk, the space engineer was already
thinking about when it would become a piece of space junk. After all, SwissCube
was programmed to pass close to the area where the Iridium and Kosmos
satellites collided a few months earlier. The debris from that collision was
still moving around in space.
In 2012, in
response to the dangers posed by space debris to SwissCube, Richard-Noca and
the EPFL Space Center launched a space clean-up project, known as CleanSpace.
At the same time but independently, Luisa Innocenti, a physicist at ESA,
convinced the agency to launch a programme, which it also named
CleanSpace.
Special project
Eight years
later, the EPFL initiative became a start-up, renamed ClearSpace. And as
already announced in autumn 2019, it was chosen by ESA from among 13 candidates
- including several European industrial giants - to do the job. The start-up
has just increased its workforce from five to 20 people.
This is the
first time that ESA has purchased an end-to-end service contract rather than
operating the mission itself. More importantly, it is the first time that a
space agency has ever committed such a large sum of money to a start-up. ESA
will provide €86 million (CHF93 million), with ClearSpace responsible for
finding the €24 million (CHF26 million) needed to complete the budget.
But as was
pointed out during this week's online press conference, ClearSpace is much more
than a start-up. The company has spent the past year bringing together a
consortium of institutes and industries from eight European countries,
including giants such as Airbus and Switzerland's arms maker RUAG - which,
among other things, builds the payload fairings of the Ariane rockets. Thus
while the ClearSpace-1 satellite still exists only on paper, its construction
will be carried out by experienced firms. ESA will also carry out the necessary
checks before each instalment of funding is paid out.
Many unknowns
ClearSpace-1
is scheduled to take off in 2025 on board the European Vega rocket. Its mission
is to capture space debris and then place itself in a re-entry orbit with the
space junk. Friction will cause the captured debris and ClearSpace-1 to burn
up, leaving space a tiny bit cleaner and safer.
The chosen
target is a VESPA. It has nothing to do with the famous Italian scooter,
although it is not much bigger or heavier - 112 kilogrammes (246 lbs). The VEga
Secondary Payload Adapter (VESPA) is a small metal cone that is used to
separate satellites from each other when they are carried by the same rocket.
It was launched in 2013 by a Vega rocket in a low orbit of 800 km from Earth.
However, no
one has ever captured an "uncooperative" object in space. The VESPA,
which moves freely by turning on itself, has no operator or engine.
"We've
all seen in movies an astronaut who, when trying to catch a tool, makes a false
move and the tool disappears into space like a flying golf ball. It is exactly
the same with the VESPA," says Innocenti. ClearSpace-1 will have to open
its four arms wide to smoothly capture the object.
Another
difficulty is the Sun, which blinds the cameras and could make the target
invisible at the crucial moment. The "debris hunter" will therefore
have to move forward step by step and constantly re-calibrate each movement
with the help of artificial intelligence. And if the capture is successful,
ClearSpace-1 will have to deal with a completely new object, whose dynamics
will have to be understood before deciding where and how to drop it.
More than a cleaner
In the end,
ClearSpace-1 will burn up with its captured debris in the upper atmosphere. That
seems like an awful lot of money to pay to get rid of a single piece of space
junk. Not according to the ESA and ClearSpace.
The 2025
mission should be the first in a long series, with the prospect of developing a
spacecraft capable of disposing of several orbiting objects at a time. There is
already talk of five or even ten pieces of debris being destroyed in a single
mission.
And there's
more: ClearSpace's technologies could also be used to refuel or make repairs to
extend the life of some satellites. In the longer term, there are also plans to
assemble spacecraft in orbit for long-distance travel that would be far too
heavy to escape the Earth's gravitational pull in one piece.
"Our
goal is to offer low-cost and sustainable in-orbit services," says Luc
Piguet, director of ClearSpace. He estimates a potential market that could one
day be worth "between a few hundred million and several billion dollars a
year".
Unclear responsibilities
Who is
responsible for space debris and who pays for its disposal? The Space Treaties
adopted by the United Nations in 2002 speak only of the responsibility of
states in the event of an accident and say nothing about the role of private
actors. Does that mean the debris is nobody's business?
Not quite.
There is a difference between old and new (or future) debris. Now very precise
rules exist that space agencies and private entities must follow, even if they
are not legally binding. A satellite launcher, for example, must plan to
re-enter the atmosphere after 25 years and carry enough fuel to manage the
manoeuvre itself.
As Piguet
points out, "we are launching more and more satellites. Since 2010, the
number of objects in orbit has increased 16-fold". This phenomenon is
mainly due to satellite internet constellations, such as Starlink from SpaceX
or OneWeb. But these players are "very aware of the problem and very
proactive", says the boss of ClearSpace.
So the big
problem is the old debris. And Piguet is adamant that "it's now or
never!"
"There
are discussions at the United Nations to introduce a tax on launches, which
would be used to fund a space clean-up fund to be managed by the UN," says
Innocenti. "But these are discussions between diplomats. It's a bit like
global warming, we feel like we've got all the time in the world, so we're
moving very slowly.”