- Introduction – define space debris.
- Point out the costs associated with space debris.
- Mention the initiatives taken by India in this regard.
They can be both natural (asteroids, meteoroids) and manmade (defunct satellite, spacecrafts, stages of rockets, satellite explosions or collisions). While most meteoroids orbit about the Sun, most artificial debris remain principally in the Earth orbit. They sometimes enter into earth’s atmosphere. They are also termed as orbital debris, space junk, etc., having no functional utility.
Costs associated with space debris:
- Kessler syndrome is the phenomenon in which the amount of space debris becomes so large that it creates cascading problems for satellites & mission planners.
- With the rise in launch of mega-constellations like Space X’s Starlink, Project Kuiper of Amazon, etc., there is compounding risk of collision or explosion in space creating thousands of debris.
- Since both debris and spacecraft / satellites are travelling at extremely high speeds, a tiny impact can potentially damage them, often aborting the mission. Millimetre sized debris has the highest mission ending risk to most robotic spacecraft operations in low-earth orbit.
- Collision with debris can cause spacecraft explosion which can kill astronomers, or can destroy strategic space assets.
- Space debris protection and mitigation measures are costly to satellite operators. According to OECD, such costs amount to 5-10% of the total mission costs.
- It can disrupt unique applications like weather forecasting, earth sciences, communications, etc., which can negatively affect economic & social activities.
- Network for Space Objects Tracking and Analysis (NETRA) tracks space debris within 1,500 km with an optical telescope for surveillance. It has connected radars, data processing units, and a control centre.
- It will build India’s Space Situational Awareness (SSA). ISRO had performed 19 collision avoidance manoeuvres in 2021, of which 14 were in Low Earth Orbit and 5 in Geostationary Orbit.
- Multi Object Tracking Radar (MOTR) is developed by Satish Dhawan Space Centre allowing ISRO to track 10 objects simultaneously, including space assets & debris.
- ISRO is part of the Inter-Agency Space Debris Coordination Committee to coordinate global efforts to reduce man-made and natural space debris by identifying debris mitigation
None of the existing international treaties or legislations have any direct reference to space debris. So, space debris should be clearly defined in them along with absolute responsibilities to enhance space accountability. A holistic framework comprising of mitigation procedures needs to be implemented considering both scientific perspective & legal approach.