With the mission, ISRO aims to exhibit technologies needed for spacecraft rendezvous, docking, and undocking using two small satellites which have been mastered by only an elite group of spacefaring nations

SRIHARIKOTA (TIP): The Indian Space Research Organisation (ISRO) successfully launched the Space Docking Experiment (SpaDeX) mission on Monday , December 30, 2024.

The PSLV C60 rocket carrying two small satellites, SDX01 (Chaser) and SDX02 (Target), along with 24 payloads, lifted off from the first launchpad of the Satish Dhawan Space Centre in Sriharikota at 10 p.m. About 15 minutes after liftoff, the two small spacecraft weighing about 220 kg each were launched into a 475-km circular orbit as intended.

“The rocket has placed the satellites in the right orbit which is into a 475-km circular orbit. The spacecraft’s solar panels have been deployed successfully. The two SpaDeX satellites have moved one behind another so over a period of time it will pick up travel further distance, the distance will increase by 20 km over the next few days and then the rendezvous and docking process will start. The docking process can happen in another one week; the nominal time will be approximately January 7,” said ISRO Chairman S Somanth.

With the SpaDeX mission, ISRO aims to exhibit technologies needed for spacecraft rendezvous, docking, and undocking using two small satellites which have been mastered by only an elite group of spacefaring nations.

The demonstration of this technology is essential for futuristic missions such as sending an Indian astronaut on the Moon, sample return from the Moon, the building and operation of the Indian Space Station.

ISRO said that the demonstrated precision of the PSLV vehicle will be utilized to give a small relative velocity between the Target and Chaser spacecraft at the time of separation from the launch vehicle.

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“This incremental velocity will allow the Target spacecraft to build a 10-20 km inter-satellite separation with respect to the Chaser within a day. At this point, the relative velocity between the Target will be compensated using the propulsion system of the Target spacecraft,” ISRO said.

ISRO added that at the end of this drift arrest maneuver, Target and Chaser will be in the same orbit with identical velocity but separated by about 20 km, known as Far Rendezvous.

“With a similar strategy of introducing and then compensating for a small relative velocity between the two spacecraft, the Chaser will approach the Target with progressively reduced inter-satellite distances of 5 km, 1.5 km, 500 m, 225 m, 15 m, and 3 m, ultimately leading to the docking of the two spacecraft,” it added.

U R Rao Satellite Centre Director M. Sanakaran said the docking is expected between January 7 and 10.

Twenty-four PS4-Orbital Experiment Module (POEM-4) payloads will also onboard the PSLV-C60 SpaDeX mission.