According to web portal Spaceflight, ISRO is set to launch its first-ever Space Docking Experiment (SpaDEX) mission on December 30, 2024, using the PSLV-C60 rocket. This mission marks a significant milestone for India as it aims to demonstrate autonomous docking technology in space, a capability that only a few countries, including the US, Russia, and China, have mastered.

Two satellites named "Chaser" and "Target," each weighing 400 kg will perform their docking maneuver at an altitude of approximately 700 km.

The mission aims to achieve several critical objectives:

The Chaser will autonomously reendezvou to dock with the Target satellite, the mission will be demonstrating precise control to maintain relative positions in orbit. Another feature of the docking is testing the ability to control one satellite using the attitude control system of another while docked. ISRO explores for the first time to use robotic technologies for in-space manipulation. The experiment aims to demonstrate technology for capturing satellites and debris in space, contributing to ISRO's broader goal of achieving a debris-free environment by 2030.

The capture will utilize a long tether attached to the cubesat, which will be deployed to grab and secure it. This method is designed to facilitate the deorbiting of both the satellite and any debris captured, ensuring they burn up upon re-entry into the Earth's atmosphere

The tethered satellite capture will involve a free-flying cubesat that will be tethered to the POEM (PS4 Orbital Platform) and captured by a robotic arm fitted on the platform.

Implementing this technology involves several technical challenges, including precise targeting of fast-moving objects, effective tether deployment and control, and safe deorbiting of captured debris

Significance

If successful, SpaDEX will enhance India's capabilities in space operations and is expected to pave the way for future projects such as:

Chandrayaan-4: A lunar sample return mission.

Bharatiya Antariksha Station: India's proposed space station.

Gaganyaan: India's human spaceflight program.

The mission's success could also extend the operational life of geostationary satellites by allowing for in-orbit servicing and refuelling, which is crucial for long-term space missions.

ISRO has emphasised that this mission represents a collaborative effort with significant contributions from private sector partners, showcasing India's growing capabilities in space technology development.

This experiment represents a significant step in developing technologies for space operations that could enhance satellite manoeuvrability and contribute to sustainable practices in space exploration.