ISRO Achieves Major Milestone As PSLV's POEM-3 Leaves Zero Debris At Re-Entry Into Earth

In another milestone for the Indian Space Research Organisation, its PSLV Orbital Experimental Module-3 (POEM-3) re-entered the Earth’s atmosphere on March 21 without leaving any debris in orbit.

After completing its mission of placing all satellites into their desired orbits, the terminal stage of PSLV was transformed into a 3-axis stabilised platform, known as the POEM-3.

The stage was then de-orbited from 650 km to 350 km, which helped its early re-entry. Measures were taken to passivate the stage and remove residual propellants so that any accidental break-up risks were minimised.

The operation took place on January 1, 2024. “The PSLV-C58/XPoSat mission has practically left zero debris in orbit,” the space agency said.

POEM-3 was configured with a total of nine different experimental payloads to carry out technology demonstrations and scientific experiments on the newly developed indigenous systems.

The POEM, a cost-effective platform for carrying out short-duration space-borne experiments, has served to open up new opportunities for academia, startups, and NGEs to experiment with their new payloads. This opportunity has been effectively utilised by numerous startups, universities, and NGEs for carrying out experiments in space, which include electric thrusters, satellite dispensers, and star-tracking.

POEM also incorporates new features such as total avionics in single-chain configuration, industrial-grade components in avionics packages including Mission Management Computer, standard interfaces for electric power, telemetry & telecommand, and new in-orbit navigation algorithms making use of rate-gyro, sun sensor, and magnetometer.

The Vikram Sarabhai Space Centre (VSSC) has taken the lead in conceptualising and realising the POEM by augmenting the fourth stage of PSLV.

PSLV-C58/XPoSat is the third such mission in the series, with POEMs being successfully scripted each time.  Till near re-entry, POEM-3 was tracked by ISTRAC ground stations. The Multi-Object Tracking Radar (MOTR) at Shriharikota also tracked the PS4 stage till the morning of March 21.