‘POEM’ Platform

In Context

• ISRO successfully launched the PSLV Orbital Experimental Module or ‘POEM’.

What is POEM?

• The PSLV Orbital Experimental Module (POEM) activity performs in-orbit scientific experiments using the spent PS4 stage as an orbital platform.
•  It is the first time that the PS4 stage would orbit the earth as a stabilised platform. 
•  POEM derives the power from the solar panels mounted around the PS4 tank and a Li Ion battery.
• It navigates using four sun sensors, a magnetometer, gyros & NavIC. 

• POEM has a dedicated Navigation Guidance and Control (NGC) system for attitude stabilisation, which stands for controlling the orientation of any aerospace vehicle within permitted limits.
  •  The NGC will act as the platform’s brain to stabilise it with specified accuracy.

• It carries dedicated control thrusters using Helium gas storage. It is enabled with a telecommand feature.
  • POEM carries six payloads including two from Indian Space Start-ups M/s Digantara and M/s Dhruva Space, enabled though IN-SPACe and NSIL.

Has ISRO repurposed and used PS4 rocket junk earlier?

• The Indian space agency first demonstrated the capability of using PS4 as an orbital platform in 2019 with the PSLV-C44 mission that injected Microsat-R and Kalamsat-V2 satellites into their designated orbits.
  •  The fourth stage in that mission was kept alive as an orbital platform for space-based experiments.

Source:IE