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ISRO: INSAT-4B Successfully Decommissioned through 11 Re-orbiting manoeuvres 

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INSAT-4B decommissioned after 11 manoeuvres in spaceIndian Space Research Organisation (ISRO) has decommissioned the INSAT-4B, an Indian communications satellite that forms part of the Indian National Satellite System on 24th January 2022 through 11 re-orbiting manoeuvres that pushed the satellite into the desired orbit mandated by the IADC space debris mitigation guidelines. 

  • The finally achieved orbit is about 340km above geostationary (GEO) altitude, in perfect compliance with IADC guidelines for space debris mitigation of GEO objects.


The decommissioning of the satellite was to comply with the United Nations(UN) and the Inter-Agency Space Debris Coordination Committee (IADC) recommended space debris mitigation. 

The INSAT-4B has completed around 14 years of on-orbit operations. 

This Telecommand intensive operation was executed between the 70-74 degree East longitude region to avoid radio frequency interference with the other operational GEO satellites.

Post Mission Disposal (PMD):

The satellite underwent Post Mission Disposal (PMD) at the end of its service, followed by decommissioning as a part of the efforts of India to preserve the long term sustainability of outer space. 

This is the 21st Indian geostationary (GEO) satellite to undergo PMD.

As a part of standard practice, the required propellant for the re-orbiting was included in the initial fuel budget. 

IADC space debris mitigation guidelines:

In compliance with the IADC space debris mitigation guidelines, a GEO object, at its end-of-life, should be raised to a nearly circular orbit well above the GEO belt to prevent its orbit from coming back into the GEO protected region within 100 years of re-orbiting.

The minimum orbit raise required is 273 Km, this was achieved through the 11 re-orbiting manoeuvres executed during 17th – 23rd January 2022. 

  • The finally achieved orbit: 340km above geostationary (GEO) altitude. 

About INSAT-4B:

INSAT-4B was launched on 12th March 2007 to provide DTH (Direct To Home) and other communication services. 

INSAT – 4B Spacecraft is the second in the INSAT 4 series of spacecraft and is configured with exclusive communication payloads to provide services in Ku and C frequency bands. 

INSAT -4B was co-located with INSAT- 3A at 93.5 degrees East longitude.

Weight3025 kg (at Liftoff)
Onboard Power5859 W
Launch SiteFrench Guiana
Launch VehicleAriane5
Orbit TypeGeostationary Orbit 

About Indian Space Research Organisation (ISRO):

Chairman– S Somanath
Headquarters– Bengaluru, Karnataka