ISRO achieved a significant step towards India’s space station dream by successfully lowering the fourth spent stage of the PSLV-C58 launch vehicle. This stage, known as PS4, descended to a 350 km orbit after placing the X-Ray Polarimeter Satellite (XPoSat) into a 650 km orbit.
In the mission update, ISRO stated, “The PS4 stage is successfully brought down to a 350 km orbit.”
Following the completion of the primary objective – injecting XPoSat into a 650 km, 6-degree orbit – the PS4 stage underwent an orbit change through two restarts, reaching a 350 km, ~9.6-degree orbit. The remaining propellant in PS4 was safely disposed of using the main engines, paving the way for future atmospheric re-entry experiments.
ISRO’s PSLV Orbital Experimental Module (POEM) enables scientific experiments using the spent PS4 stage as an orbital platform. This platform is equipped with Flexible Solar Panels, a 50Ah Li-ion battery, and avionic systems for precise control during payload testing.
Key experiments on the PSLV Orbital Experimental Module include:
1. Bellatrix Aerospace: Testing Rudra 0.3 HPGP, a green monopropellant thruster, and ARKA-200, a heater-less hollow cathode for Hall thrusters.
2. InspeCity Space Labs:Testing the Green Impulse TrAnsmitter (GITA), a green bipropellant CubeSat propulsion unit.
3. TakeMe2Space:Testing Radiation Shielding Experimental Module (RSEM) designed to evaluate the effectiveness of Tantalum coating, enhancing CubeSat lifespan.
4. LBS Institute of Technology for Women: Contributing the Women Engineered Satellite (WESAT), measuring solar irradiance and UV Index.
5. KJ Somaiya Institute of Technology: Featuring BeliefSat-0, an amateur radio satellite.
6. ISRO’s Vikram Sarabhai Space Centre (VSSC):Contributing the Fuel Cell Power System (FCPS) and Silicon-based High Energy Cell.
7. Physical Research Laboratory: Sending the Dust Experiment (DEX) to measure interplanetary dust count.
Among these experiments, the testing of FCPS in the lower orbit aligns with ISRO’s broader strategy to validate technologies crucial for the proposed Indian Space Station’s success.