Space saving measures: Addressing the debris problem

Earlier this month, the Space Security Index (SSI) 2017, an international research project headed by Canadian NGO Project Ploughshares, was released.

This is the 14th edition of the annual, covering the period between January and December 2016. The 240-page report was collaborative effort by researchers from the University of Adelaide, The George Washington University, McGill University, Project Ploughshares, The Simons Foundation, and Xi’an Jiaotong University.

Like all its previous reports, the SSI 2017 focuses on the “security and sustainability of outer space as an environment that can be used safely and responsibly by all”. Taking a wide interpretation of the phrase, the report covers all aspects of the space industry in 2016, including space policy, agency and commercial space activities, international agreements, and space-based disaster management. A reading of the report presents an excellent overview of the happenings of 2016 as well as the general trends over the years.

The biggest threat: Space debris

As SSI’s primary focus – as its name suggests – is the security of outer space, the report begins by singling out space debris as the biggest threat to space security today. In it is described the current space debris situation, the problems caused by space debris, and the efforts taken to mitigate it.

The space debris situation

According to the report, there are several million pieces of orbital space debris today, based on data from the U.S. Department of Defense’s (DoD) Space Surveillance Network, which tracks artificial objects orbiting Earth. Of the several million, 23,000 pieces measure 10 cm or larger in diameter, while at least 500,000 measure 1 cm or larger. Of these, about half are in Low Earth Orbit (LEO), especially the Sun-Synchronous Orbit (SSO) popular for Earth Observation (EO).

In recent years, the report says, there have been two significant contributors to space debris. The first is China’s 2007 anti-satellite missile test (ASAT), which intentionally destroyed its Fengyun-1C satellite in Low Earth Orbit (LEO). The second is the collision of Russia’s LEO communications satellite Kosmos 2251 with Iridium 33 in 2009, which was the first ever satellite collision in Earth Orbit. Fengyun-1C, according to SSI, now accounts for roughly 20% of all catalogued objects, while the collision, along with eight other space missions, account for another 10%  of all debris.

Fortunately, says the report, the number of space debris created each year is decreasing. However, the dangers posed by existing objects still remains.

Debris created in 2016

The report cites 9 significant incidents in 2016 that caused space debris – the explosion of a Proton upper stage in Geostationary Orbit (GEO), the breakup of three Proton-DM ullage motors in Medium Earth Orbit (MEO), the breakup of two U.S. LEO satellites, the breakup China’s retired Beidou-G2 GEO satellite, an accident leading to the breakup of Japan’s Hitomi space observatory, and unexplained debris around India’s remote sensing satellite RISAT-1 in LEO. Altogether, these caused at least 87 observed pieces of debris.

Damage caused by debris

In 2016, there were a few minor disruptions to space activity due to the impact of space debris. Most significant of these was an undetected piece of debris approaching the International Space Station (ISS), which necessitated the crew taking shelter in the Soyuz spacecraft attached to the ISS.

How to remove space debris?

So far, according to the report, there has been no attempt at Active Debris Removal (ADR), although several agencies and private companies are working towards developing ADR technology. The SSI 2017 summarizes these attempts:

  1. September 2016 saw the launch of the University of Toronto’s nanosatellite CanX-7, with a secondary mission of demonstrating drag-sail technology to deorbit satellites.
  2. On 27 January 2017, JAXA’s Kounotori Integrated Tether Experiments (KITE) was deployed from the ISS, carrying a 700-m electrodynamic tether designed to encourage electrical conductivity to help to deorbit the spacecraft. However, the tether failed to deploy and the mission was declared a failure in February.
  3. In June 2016, China launched Aolong-1 (Roaming Dragon), a smallsat with a robotic arm meant to demonstrate the removal of a space debris object.
  4. In December 2016, EUMETSAT announced that its MetOp-A meteorological satellite would conduct maneuvers to move the satellite from a Sun synchronous orbit to a slightly drifting orbit, allowing it to conduct a deorbit burn at the end of its life in 2021 or 2022.
  5. ESA’s TeSeR (Technology for Self-Removal of Spacecraft) project will research and develop three strategies for the ‘self-removal’ of satellites.
  6. ESA’s RemoveDebris research programme will conduct its first ADR mission, known as E.deorbit, scheduled for 2023. This will use a net deployment system developed by Polish company SKA Polska.
  7. Singapore-based firm Astroscale will launch its Elsa-1 satellite, planned for 2018. The satellite will use an adhesive-based method to capture debris.
  8. U.S. Aerospace Corporation is developing Brane Craft, which will be deployed as a fleet to clean up derelict CubeSats. It is still in an early stage of development, with no scheduled launch date.

Conclusion

The report also covers the work of international organisations such as the UN Committee on the Peaceful Uses of Outer Space (UN COPUOS) and the Inter-Agency Space Debris Coordination Committee (IADC), and cites the growing number of CubeSats as a potential problem, especially with the advent of constellations. It also shows how there is a lack of will, transparency and funding to truly seek a solution to the problem.

Aside from space debris, the extensive SSI discusses in great detail other threats, e.g., the battle for bands in the Radio Frequency (RF) spectrum and orbital positions, space weather, and Near Earth Objects (NEO) such as asteroids. Other topics, such as spaced-based military power and the use of nuclear energy in space, are also covered, along with the future of the Outer Space Treaty.

The full Space Security Index 2017 report can be found here.

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