ISRO’s RISAT-2 satellite makes re-entry into Earth’s atmosphere

ISRO’s RISAT-2 satellite makes re-entry into Earth’s atmosphere

Subject: Science and Technology

Context-

• ISRO’s RISAT-2 satellite, launched in 2009, has made an uncontrolled re-entry into the Earth’s atmosphere into the Indian Ocean near Jakarta.

No explosion expected-

• Since its injection, RISAT-2’s radar payload services were provided for various space applications.
• On re-entry, there was no fuel left in the satellite and hence there are no contaminations or explosion by fuel is expected.
• Studies confirmed that the pieces generated due to aero-thermal fragmentation would not have survived re-entry heating and hence no fragments would have impacted Earth.
• The orbital data available from USSPACECOM were regularly used to predict the re-entry time and impact
• The Indian System for Safe and Sustainable Space Operations Management (IS4OM) facility in ISTRAC, Bengaluru had been monitoring the re-entry for the last one month with analysis carried out by VSSC and ISTRAC teams through its in-house developed analysis software and tracking the object utilising Multi-Object Tracking Radar (MOTR) at SDSC, Sriharikota.

About the Radar Imaging Satellite-2 (RISAT-2)-

• It was an Indian radar imaging reconnaissance satellite that was part of India’s RISAT programme.
• It was launched by the PSLV-C12 launch vehicle 13 years ago in 2009.
• The satellite has a mass of 300 kg (660 lb).
• It is India’s first dedicated reconnaissance satellite.
• RISAT-2 was built at an accelerated pace following the 2008 Mumbai attacks, due to a delay with the indigenously developed C-band for RISAT-1.
• The launch of RISAT-1 came several years after that of RISAT-2.
• The RISAT-2 mission was prioritised over RISAT-1 following the 2008 Mumbai attacks, resulting in RISAT-1 being delayed by several years.
• The principal sensor of RISAT-2 was an X-band synthetic-aperture radar (SAR) from Israel Aerospace Industries (IAI).

Technical capabilities-

• RISAT-2 was India’s first satellite with a synthetic-aperture radar (SAR).
• It possesses day-night as well as all-weather monitoring capability.
• Potential applications include tracking hostile ships at sea that are deemed a military threat to India.
• It is designed to monitor India’s borders and as part of anti-infiltration and anti-terrorist operations.
• ISRO said that though the initial designed life of the satellite was four years, due to proper maintenance of orbit and mission planning by the spacecraft operations team in ISRO and by economical usage of fuel, RISAT-2 provided very useful payload data for 13 years.

About Indian System for Safe and Sustainable Space Operations Management (IS4OM)-

• The control centre would facilitate the intensified activities foreseen for Space Situational Awareness & Management (SSAM) in view of the increasing debris population and operational space assets.
• IS40M will undertake
  • Observation and monitoring of space objects and space environment,
  • Processing the observations for orbit determination
  • Object characterization and cataloguing
  • Analysis of space environment evolution
  • Risk assessment and mitigation
  • Data exchange and collaboration.
• The system would safeguard all Indian Space assets by mitigating the collisional threats from space objects through specific orbit manoeuvres and complying with international guidelines on post-mission disposal and satellite end-of-life operations.
• It would assimilate the tracking data of inactive satellites from indigenous observation facilities and generate useful information from bare observations through analysis.
• For sustainable use of space, the control centre would enable research activities pertaining to active debris removal, space debris modelling and mitigation.
• IS4OM facility will aid India in achieving its SSA (Space Situational Awareness) goals by providing comprehensive and timely information on the space environment to users.
  • Space Situational Awareness (SSA) refers to the knowledge of the space environment, including the location and function of space objects and space weather phenomena.
  • SSA is generally understood as covering three main areas: Space Surveillance and Tracking (SST) of man-made objects.