The growing threat of space debris
There is a continuing increase in space debris that poses a growing threat to economically vital orbital regions. Many experts like satellite operators around the world, including those flying telecom, weather, navigation, broadcast and climate-monitoring missions, are putting their efforts on controlling space debris.
Since the beginning of the space age there have been almost 5000 launches by all spacefaring nations.The result of that is a lot of human-made space debris of which about two-thirds originate from orbital break-ups – more than 240 explosions – and fewer than 10 known collisions.
In 2009 a collision between America’s Iridium-33 civil communications satellite and Russia’s Kosmos-2251 military satellite demolished both and produced a large amount of debris – more than 2200 tracked fragments.
Scientists evaluate the level of space debris in Earth’s orbit to be around 29 000 objects bigger than 10 cm, 670 000 pieces bigger than 1 cm, and more than 170 million above 1 mm.
Heiner Klinkrad, Head of ESA’s Space Debris Office, said that any of these objects can harm an operational spacecraft.
Klinkrad pointed out that satellite collisions with fragments above 10 cm would be catastrophic releasing hazardous debris clouds that can lead to further catastrophic collisions that may produce increasing debris in some orbits.
Space debris mitigation measures, if properly implemented by satellite designers and mission operators, can curtail the growth rate of the debris population. Active debris removal, however, has been shown to be necessary to reverse the debris increase, Klinkrad explained.
The ultimate aim is to prevent collisional cascading from happening over the next few decades.
According to Thomas Reiter, Director of Human Spaceflight and Operations, this is a global task, active removal is a challenge that should be undertaken by joint efforts in cooperation with the world’s space agencies and industry.
Reiter added that ESA, as a space technology and operations agency, has identified the development of active removal technologies as a strategic goal.
The 6th European Conference on Space Debris is taking place at ESOC, ESA’s European Space Operations Centre, Darmstadt,Germany (April 22–25, 2013).
Featured image credit: Fraunhofer FHR