ISRO To Set Up Tracking of space Debris

Space Junk and NETRA Project: With space junk posing an increasing threat to Indian assets in space, the Indian Space Research Organization (ISRO) is building up its orbital debris tracking capability by deploying new radars and optical telescopes under the Network for Space Objects Tracking and Analysis (NETRA) project.


  • Space debris tracking radar with a range of 1,500 km and an optical telescope will be inducted as part of establishing an effective surveillance and tracking network under NETRA.
  • The government has given the go-ahead for the deployment of the radar, which will be capable of detecting and tracking objects 10 cm and above in size.
  • It will be indigenously designed and built.
  • ISRO plans to have two such radars deployed 1,000 km apart for spatial diversity.
  • Currently, ISRO has a Multi-Object Tracking Radar at Sriharikota range, but it has a limited range.
  • The SSA Control Center in Bengaluru coordinates ISRO's efforts in space situational awareness (SSA), which are administered by the Directorate of Space Situational Awareness and Management at ISRO headquarters.

What is Space Debris?

  • Space debris or space junk is a term used to describe a group of unwanted objects in Earth's orbit, whether man-made or natural.
  • Natural Debris is made up of natural bodies that orbit the sun, such as asteroids and meteors.
  • Artificial space junk or debris consists of exhausted rocket stages, dead satellites, shards of space objects, and debris from the Anti-satellite (ASAT) System.
  • These free-floating space debris, hurtling through space at a speed of 27,000 kmph in Low Earth Orbit (LEO), pose a genuine hazard as collisions involving even centimetre-sized fragments can be lethal to satellites.
  • These particles are a potential hazard for operational satellites and colliding with them can leave the satellites dysfunctional.
  • This is referred to as Kessler Syndrome, named after National Aeronautics and Space Administration (NASA) scientist Donald Kessler in 1978.
  • According to Kessler Syndrome, if there is too much space trash in orbit, it could cause a chain reaction in which more and more objects hit and create additional space junk, eventually rendering Earth's orbit uninhabitable — a Domino Effect.

Project NETRA:

  • NETRA project is an early warning system in space to detect debris and other hazards to Indian satellites.
  • NETRA Project was initiated by ISRO in August 2020.
  • Under NETRA, ISRO plans to put up the following:
  1. Many observational facilities:
  2. Connected radars,
  3. Telescopes;
  4. Data processing units and
  5. A control centre.

Note: Radars and optical telescopes are vital ground-based facilities for keeping an eye on space objects, including orbital junk.

  • They can also spot, track and catalogue objects as small as 10 cm, up to a range of 3,400 km and equal to a space orbit of around 2,000 km.
  • Once operational, it will give India its own capability in Space Situational Awareness (SSA) like the other space powers which is used to ‘predict’ threats from debris to Indian satellites.
  • It also goes so far as to serve as an unstated warning against missile or space attacks on the country.
  • Under this project, SSA was first used for low-earth orbits, or LEO which have remote-sensing spacecraft.
  • NETRA’s ultimate goal is to capture the GEO, or geostationary orbit, the scene at 36,000 km where communication satellites operate.

Why the need?

  • With countries launching more and more satellites, each one a strategic or economic asset, preventing collisions may grow increasingly difficult in the future.
  • In the year 2021, ISRO monitored 4,382 events in LEO and 3,148 events in the geostationary orbit where space objects closely approached Indian assets.
  • For protecting its space assets, ISRO was forced to perform 19 Collision Avoidance Manoeuvres (CAM).
  • Fragments from the Fengyun-1C satellite (part of the anti-satellite test (ASAT) by China in 2007) and the Cosmos 2251-Iridium satellite collision in 2009 accounted for the maximum number of these threats.
  • The observations also covered 84 “close approaches of less than one km” between Starlink satellites and Indian assets.