ISRO to launch its key Spadex mission on December 30

Context: The Indian Space Research Organisation will end the year with its SPADEX
mission. The launch of two small satellites to demonstrate docking in space, is
about to take place on December 30 at 9:58 pm from the country’s spaceport at
Shriharikota. Docking is the process where two satellites are aligned and then
joined in space, a necessity for missions that the space agency hoped to
achieve in the future such as Chandrayaan-4 or setting up the Bharatiya
Antariksh Station. The last stage of the rocket will also be utilised to
demonstrate 24 payloads, including a robotic arm to capture space debris and an
experiment to demonstrate seed germination and plant growth up to two leaves in
space.

Key points

·       Overview: ISRO is
preparing to launch a record 24 scientific experiments on board the POEM
satellite under the Spadex Mission.

·       SpaDeX
Mission: The Space Docking Experiment (SpaDeX) is a groundbreaking mission by the
Indian Space Research Organisation (ISRO) aimed at developing autonomous space
docking technology. The mission involves PSLV-C60 as the launch vehicle to
demonstrate in-space docking technology using two small spacecraft: Chaser
(SDX01) and Target (SDX02). This technology is a critical milestone for future
lunar missions, the development of the Bharatiya Antariksh Station (BAS), and
other advanced space endeavours.

·       Mission
Overview: Docking and demonstration - After docking, the mission will
demonstrate electrical power transfer before undocking for payload operations.

Separation
dynamics - Target and Chaser spacecraft will separate with an initial velocity
difference to achieve 10-20 km inter-satellite separation. Propulsion systems
will be used to align spacecraft into the same orbit, achieving Far Rendezvous.

Orbit - 470 km circular
orbit at a 55-degree inclination.

Launch vehicle - PSLV-C60.

·       PSLV
Orbital Experimental Module (POEM): Developed by Vikram
Sarabhai Space Centre (VSSC). Repurposes the fourth stage of PSLV into an
orbital station for scientific experiments. First used in the PSLV-C53 mission
(2022) to minimize space debris. Equipped with a Navigation Guidance and
Control (NGC) system for attitude stabilization.