PSLV rocket with satellites of European Space Agency lifts off on ISRO rocket from Sriharikota

The proposed launch was delayed after an anomaly was detected in the satellite propulsion system.

Chennai: Indian Space Research Organisation (ISRO) on Thursday successfully launched two PROBA-3 satellites of the European Space Agency (ESA), designed to study the outer atmosphere of the Sun, from the Satish Dhawan Space Centre (SDSC) in Sriharikota near here.

At 4.04 pm, PSLV, the Indian space agency’s trusted workhorse, soared into the skies with the two spacecrafts, after the launch was rescheduled after an anomaly was detected on Wednesday, just an hour before the mission’s launch.

The mission also introduced precision formation flying technology as both satellites -- Coronagraph and Occulter – were launched together in a stacked configuration, the first-of-its-kind attempt. The launch was done by NewSpace India Limited (NSIL), the commercial arm of Isro, for its client, ESA.

Together with Isro’s solar mission, Aditya L1, the satellites launched on Thursday will help bring “fantastic science outcomes” in the coming weeks and months. As planned, the two satellites, which will study the Sun's corona or the surrounding atmosphere for scientific observation, were placed into the “right orbit” around 18 minutes after lift-off from the first launchpad of the SDSC.

“PSLV-C59/PROBA-3 Mission is successfully accomplished. The spacecraft has been placed in the right orbit, which is a very highly elliptical orbit of almost 600 km perigee (closest point to earth) and 60,000 km at its apogee, the farthest point with an inclination of 59 degree,” Isro Chairman S Somanath said.

He also announced that ISRO’s next project would be the Space Docking Experiment named SpadeX, which is likely to be launched by the end of this month.

Thursday’s launch was PSLV’s 61st mission, reinforcing the reliability of the launch vehicle which is known as the ISRO’s “workhorse.” After soaring into the skies, the PSLV successfully separated the two satellites and placed them into the intended orbit, which will be positioned at the desired orbit by the scientists of ESA in Belgium.

Josef Aschbacher, Director General, ESA, said almost instantaneously after separation, Yatharagga station in Australia began to receive the spacecraft's signal. “Telemetry is flowing to ESA's mission control centre in Belgium! Go Proba, go!,” he wrote on his X page.

Proba-3 will function as an orbital laboratory, demonstrating acquisition, rendezvous, proximity operations and formation flying, while validating innovative metrology sensors and control algorithms, opening up novel methods of mission control. The satellites adopted a fixed configuration in space, 150m apart while lined up with the Sun so that OSC blocks out the brilliant solar disk for the CSC.

“This will open up continuous views of the Sun’s faint corona, or surrounding atmosphere, for scientific observation,” the agency said.

NSIL Chairman and Managing Director D Radhakrishnan said this was the first time that the PSLV has gone into such an elliptical orbit of about 60,000 km).

"I have seen PSLV missions going to GTO (Geostationary Transfer Orbit) or sub-GTO, but reaching a 60,000 km orbit for ESA is really special. Proba-3 satellite is a single stack which has two spacecraft onboard which will get separated in the coming months," he said.