• Japan’s Astroscale, which specialises in orbital debris removal and satellite servicing, has agreed with Bengaluru-based space companies Digantara and Bellatrix Aerospace to collaborate on technology and services.

• This marks a significant step for Astroscale as it expands its operations into the Asia-Pacific region outside of Japan.

• Astroscale Japan, a subsidiary of Astroscale Holdings Inc., is developing cutting-edge solutions for in-orbit servicing and space debris mitigation.

• Astroscale is already working with the Japan Aerospace Exploration Agency (JAXA) on a commercial debris removal mission slated for 2027. 

• Digantara provides space situational awareness services to monitor orbital objects and has contracts with multiple US defence agencies. 

• Bellatrix Aerospace is a leading Indian space technology company specialising in propulsion systems.

• As two prominent players in space sustainability, Bellatrix and Astroscale will leverage their expertise to create synergies across both the Indian and Japanese space ecosystems. The collaboration aims to drive active debris removal, satellite servicing, and sustainable in-orbit mobility, contributing to a cleaner and safer space environment. 

• With the increasing number of satellites in orbit, the risk of collisions and space debris is growing, posing a significant financial risk estimated at over $500 million in the next five years.

What is space debris?

• Ever since the start of the space age there has been more space debris in orbit than operational satellites.

• The amount of objects, combined mass and combined area has been steadily rising since the beginning of the space age, leading to the appearance of involuntary collisions between operational payloads and space debris. 

• Space debris encompasses both natural meteoroid and artificial (human-made) orbital debris. Meteoroids are in orbit about the Sun, while most artificial debris is in orbit about the Earth (hence the term “orbital” debris).

• Orbital debris is any human-made object in orbit about the Earth that no longer serves a useful function. Such debris includes non-functional spacecraft, abandoned launch vehicle stages, mission-related debris, and fragmentation debris.

• About 130 million pieces of space debris larger than a millimetre orbit Earth, threatening satellites now and in the future. Once a week, a satellite or rocket body reenters uncontrolled through our atmosphere. 

• They travel at speeds up to 28,000 kmph, fast enough for a relatively small piece of orbital debris to damage a satellite or a spacecraft. 

• There are half a million pieces of debris the size of a marble or larger (up to 0.4 inches, or 1 centimeter) or larger, and approximately 100 million pieces of debris about .04 inches (or one millimeter) and larger. There is even smaller micrometer-sized (0.000039 of an inch in diameter) debris.

• Even tiny paint flecks can damage a spacecraft when traveling at these velocities. A number of space shuttle windows were replaced because of damage caused by material that was analysed and shown to be paint flecks. In fact, millimeter-sized orbital debris represents the highest mission-ending risk to most robotic spacecraft operating in low Earth orbit.

• The International Space Station (ISS) orbits Earth at an altitude of just over 400 km. In the two decades since its launch, about 30 ‘collision avoidance manoeuvres’ have been performed in order to dodge space debris, with three taking place in 2020 alone. If a potential collision appears imminent, and there is no time to move the Station, they can take emergency shelter.

• In 1996, a French satellite was hit and damaged by debris from a French rocket that had exploded a decade earlier.

• In February, 2009, a defunct Russian spacecraft collided with and destroyed a functioning US Iridium commercial spacecraft. The collision added more than 2,300 pieces of large, trackable debris and many more smaller debris to the inventory of space junk.

• China’s 2007 anti-satellite test, which used a missile to destroy an old weather satellite, added more than 3,500 pieces of large, trackable debris and many more smaller debris to the debris problem.

• Not only a hazard, space debris increases the cost for satellite operators. Satellite operators in the geostationary orbit have estimated protective and mitigation measures account for about 5-10 per cent of mission costs and for lower-Earth orbits the cost is higher.

• The most important action currently is to prevent the unnecessary creation of additional orbital debris. This can be done through prudent vehicle design and operations. Cleaning up the environment remains a technical and economic challenge.

• As space debris poses a problem for the near Earth environment on a global scale, only a globally supported solution can be the answer.

• The United Nations Committee on the Peaceful Uses of Outer Space by the United Nations Office for Outer Space Affairs (UNOOSA) has paid particular attention to the issue of preventing and minimising the creation of space debris.

Safeguarding India’s space assets

• Recognising the growing importance of Space Situational Awareness (SSA) for space sustainability, ISRO System for Safe and sustainable Space Operations Management (IS4OM) has been established to focus all efforts related to spaceflight safety and debris mitigation and for dealing with the emerging challenges in operating in a congested space environment. 

• Network for Space object TRacking and Analysis (NETRA) has been approved by the government for SSA capacity building.

• ISRO adheres to the internationally accepted space debris mitigation guidelines recommended by UN-COPUOS and Inter-Agency Space Debris Coordination Committee (IADC) to the maximum possible extent.

• For all Indian launch vehicles, Collision Avoidance Analysis (COLA) is performed to select collision threat-free lift-off time within the launch window. 

• Continual assessments of any close approach risk to ISRO’s operational satellites are carried out and Collision Avoidance Manoeuvres (CAM) are performed as and when needed. 

• In case the object posing close approach risk is another active satellite, the required coordination is carried out with the owner/operator so that only one of the satellites performs the CAM. 

• Continual efforts to improve the operational methodologies for close approach assessment are pursued to adapt to the challenges posed by the surging space traffic, apart from modelling on-orbit break-up events and prediction of atmospheric re-entries of space objects, etc.

• ISRO contributes substantially to shaping the pertinent guidelines and recommendations for sustainable use of space as an active member of various international agencies dealing with safety and sustainability of outer space activities, such as Inter-Agency Space Debris Coordination Committee (IADC), International Academy of Astronautics (IAA), International Organisation for Standardisation (ISO), International Astronautical Federation (IAF), UN Long Term Sustainability Working Group.

• The Indian Space Policy places significant importance in space debris mitigation requirements and SSA capacity building.

• The recently unveiled Debris Free Space Mission (DFSM) initiative is also spearheaded by ISRO with an aim to achieve debris-free space missions by all Indian space actors, both governmental and non-governmental, by 2030. The initiative aligns with global efforts for space sustainability, positioning India as a nation prioritising safety, security, and sustainability in outer space activities.

(The author is a trainer for Civil Services aspirants.)