BENGALURU: The fifth and final Lunar-bound orbit manoeuvre for Chandrayaan-2 spacecraft was performed successfully on Sunday, beginning at 6.21 pm as planned, using the onboard propulsion system.
The duration of the manoeuvre was 52 seconds. The orbit achieved is 119 km x 127 km.
All spacecraft parameters are normal.
The next operation is the separation of Vikram Lander from Chandrayaan-2 Orbiter, which is scheduled on September 2 between 12.45 pm and 1.45 pm.
Following this, there will be two deorbit manoeuvres of Vikram Lander to prepare for its landing in the south polar region of the moon.
On Friday evening, the ISRO performed the penultimate orbit-lowering manoeuvre.
The fourth lunar-bound orbit manoeuvre fired the onboard propulsion system of the orbiter for 1,155 seconds at 6.18 pm to bring the spacecraft down to an orbital altitude of 124 km x 164 km.
On September 3, a three-second de-orbit manoeuvre will be conducted by the ISRO scientists to check if all systems are normal. Finally, on September 4, the actual de-orbit manoeuvre will be performed for about 6.5 secs to put the lander Vikram in an orbit of 35km perilune (closest to lunar surface) and 97 km apolune (farthest from the lunar surface).
For three days after September 4, the scientists will carry out all checks on the orbiting lander. On September 7, at the scheduled time of 1.40 am, the powered descent of the lander Vikram will begin -- a process which ISRO chairman has described as the “most terrifying” of the entire Rs 976 crore mission.
Vikram will land near the lunar South pole on a high plain between two craters, Manzinus C and Simpelius N, to record India as the first country ever to land near the lunar south pole.
The historic event will be witnessed live by Prime Minister Narendra Modi from ISRO Telemetry, Tracking and Command (ISTRAC) facility in Bengaluru.
After a successful landing, the rover Pragyan will emerge from Vikram and begin its exploration within 500 metres for a period of one lunar day (14 earth days), while the static Vikram and the orbiter will continue relaying scientific data back to the Deep Space Network (DSN) situated 35 Km from Bengaluru off Mysore Road.