The Polar Satellite Launch Vehicle (PSLV-C42) of Indian Space Research Organisation (ISRO) has launched two satellites – NovaSAR and S1-4 – from the Satish Dhawan Space Centre (SDSC) SHAR, Sriharikota. Both satellites were injected into the Sun Synchronous Orbit at an altitude of 583 km. The satellites belong to UK-based Surrey Satellite Technology Limited (SSTL), which has a contract with Antrix Corporation Ltd, the commercial arm of ISRO. NovaSAR carries S-band synthetic aperture radar (SAR) and automatic identification receiver payloads. The satellite applications include forestry mapping, land use and ice cover monitoring, flood and disaster monitoring, and maritime missions. It will be operated from SSTL’s Spacecraft Operations Centre in Guildford, UK.
S1-4 is a high resolution earth observation satellite meant for surveying resources, environment monitoring, urban management, and disaster monitoring. This was the 44th flight of PSLV and the 12th flight of the core alone version of the vehicle. Core alone is its lightest version without the six strap-on motors. It is used for launching smaller payloads.
The PSLV launch vehicle consists of four stages, each of which is a self-contained vehicle capable of functioning independently with own propulsion systems. During the previous launch (PSLV-C41, 12 April 2018), the XL version of PSLV with six strap-on motors was used. The vehicle successfully launched the IRNSS-1I navigation satellite to a sub-geosynchronous transfer orbit.
Many centers of ISRO contributed to this mission with the vehicle being designed and developed by Vikram Sarabhai Space Centre, Thiruvananthapuram. The second and fourth stage liquid engines came from Liquid Propulsion Systems Centre, Thiruvananthapuram and ISRO Propulsion Complex, Mahendragiri (Tamil Nadu).
The vehicle’s guidance system is from ISRO’s Inertial Systems Unit, Thiruvananthapuram, while SDSC SHAR was responsible for solid motor preparation, vehicle integration and launch infrastructure. ISRO’s telemetry tracking and command network provided tracking support. As on date, ISRO has launched 239 foreign satellites of 28 countries.