The Indian Space Research Organisation (ISRO) has successfully initiated its second launch attempt of the Small Satellite Launch Vehicle (SSLV-D2), witnessing its take-off from the Satish Dhawan Space Centre located in Sriharikota, Andhra Pradesh. The first flight of the vehicle, dubbed SSLV D1, occurred back in August 2022 but could not accurately station the satellites into orbit. In an effort to rectify the past issues, ISRO has implemented structural modifications to the equipment bay, improved the separation process for stage 2, and made logic advancements for the on-board system.
ISRO’s Protocol for Declaring Vehicles Operational
Before ISRO can declare a new vehicle as operational, it must successfully complete two development flights. The most recent vehicle that earned this operational status was the GSLV Mk III, now referred to as LVM 3, when it transported Chandrayaan-2 in 2019.
Satellites Onboard the SSLV-D2
The SSLV-D2 is tasked with placing ISRO’s earth observation satellite EOS-07 and the two co-passenger satellites – Janus-1 and AzaadiSat2, into orbit.
Janus-1 is a technological showcase satellite created by US-based Antaris along with its Indian partners XDLinks and Ananth Technologies. This six-unit cube satellite carries five payloads — two sourced from Singapore and one each from Kenya, Australia, and Indonesia.
AzaadiSat2, on the other hand, is a Cubesat that weighs about 8 kg and transports 75 different payloads. These payloads were developed under the guidance given to girl students from rural regions throughout India and were integrated by the student team of “Space Kidz India”.
EOS-07, the 156.3 kg satellite designed and developed by ISRO, has been tasked with designing and establishing payload instruments that are compatible with microsatellite buses and innovative technologies for future operational satellites.
Understanding the Small Satellite Launch Vehicle
The SSLV is a 3-stage Launch Vehicle that is furnished with three Solid Propulsion Stages and a Liquid propulsion-based Velocity Trimming Module (VTM) as a terminal. With a diameter of 2m and a length of 34m, this vehicle weighs 120 tonnes at lift-off and can launch a satellite weighing anywhere between 10 to 500 kg into a 500 km planar orbit.
The assembly of this rocket requires a small team and can be completed in a matter of days, contrasting starkly with the 6 months and approximately 600 people required for ISRO’s workhorse PSLV.
The Objective and Significance of the SSLV
ISRO has developed the SSLV with the intention of capitalising on the burgeoning small (nano-micro-mini) satellite commercial market, by offering launches on-demand. The SSLV lowers the cost access to Space, offers reduced turn-around time, provides flexibility in accommodating multiple satellites, and demands minimal launch infrastructure.