The Chandrayaan 2 spacecraft on September 1 evening underwent a small, fifth and final orbit manoeuvre to refine its circular path around the moon.
The operation lasted less than a minute, the Indian Space Research Organisation said in an update . All spacecraft parameters are normal. The lunar orbiter-lander now has an orbit of 119 km x 127 km.
With this, the focus shifts to lander-related operations.
India’s maiden touchdown on the unexplored southern region of the moon depends on two key events: the separation of the lander Vikram, which is riding atop the main craft, on Monday afternoon; & the lander’s smooth descent on the southern crater area in the wee hours of September 7.
“The fifth and final lunar bound orbit manoeuvre for Chandrayaan 2 spacecraft was performed successfully today [September 1] beginning at 1821 hrs IST as planned using the onboard propulsion system. The duration of the manoeuvre was 52 seconds,” the update said.
On September 2, the lander Vikram is scheduled to separate from the orbiter between 12.45 p.m. and 1.45 p.m. IST. On September 3 and 4, ISRO will do two de-orbit manoeuvres of the lander to ready it for its landing.
The orbiter will remain in its orbit for a planned one year.
Tentative plan for future operations after the final lunar orbit manoeuvre
Date Time (IST) Orbit around moon Vikram Separation September 02, 2019 12:45 – 13:45 Deorbit #1 September 03, 2019 09:00 – 10:00 109 km x 120 km Deorbit #2 September 04, 2019 03:00 – 04:00 36 km x 110 km Powered Descent September 07, 2019 Vikram Touch Down September 07, 2019 01:30 – 02:30
