New Delhi

While India has proved its prowess in precision landing with Chandrayaan-3, the impending SpaDeX mission will achieve a historic space docking feat, said Union Minister of State (Independent Charge) for Science and Technology Dr Jitendra Singh on Saturday.

The Indian Space Research Organisation (ISRO) aims to launch the Space Docking Experiment (SpaDeX) mission, aboard the PSLV-C60 rocket, at 21:58 IST from Sriharikota on December 30.

The mission aims to dock two satellites in space, a challenge only mastered by the US, Russia, and China, so far.

“ISRO's year-end mission is going to be a historic one as it will seek the rare feat of docking or merging or joining together two satellites in space,” Singh said, adding that “the indigenous technology used for this mission is called the ‘Bharatiya Docking System’”.

"SpaDEX will mark a milestone, showcasing India's expertise in spacecraft docking technology,” Singh noted.

The success of this mission is vital for India’s future space ambitions. Docking technology will help upcoming missions like Chandrayaan-4 and the planned Indian space station, expected to be ready by 2035. It is also crucial for the eventual manned Gaganyaan mission, expected to launch in 2026.

With SpaDeX, “ISRO will attempt to dock two satellites orbiting at speeds of 28,800 km/h”. And both satellites must be carefully manoeuvred to reduce their relative velocities to a mere 0.036 km/h”.

The two satellites, SDX01 or Chaser and SDX02 or Target, will merge to form a single unit in space.

Each satellite weighs around 220 kilograms and will orbit 470 km above Earth.

The mission aims to include performing precision rendezvous and docking manoeuvres, validating power transfer between docked spacecraft, and operating payloads post-undocking, with a two-year lifespan.

SpaDEX will also use PSLV's fourth stage, POEM-4, for experiments. The stage will carry 24 payloads from academic institutions and startups. These experiments will utilise the microgravity environment in orbit.