Call of The Moon
India achieved a landmark in its space odyssey on September 7 when the Lunar lander, Vikram, named after Dr.Vikram A. Sarabhai, touched the surface of the Moon. The Chandrayaan-2 lunar mission attained 90 to 95 % success, according to Indian Space Research Organisation.
Vikram lost contact with the earth station minutes before its scheduled touchdown. It was located later by the Orbiter, which is all set to continue its journey in the orbit for seven years.
A chronicle of the mission, as outlined by ISRO, follows:
July 22: Chandrayaan-2 spacecraft launched by GSLV MkIII-M1 successfully from Satish Dhawan Space Centre SHAR, Sriharikota.
July 24: First earth bound orbit raising manoeuvre for the spacecraft performed successfully.
July 26: The second earth bound orbit raising manoeuvre performed successfully.
July 29: Thethird earth bound orbit raising manoeuvre performed successfully.
August 2: The fourth earth bound orbit raising manoeuvre performed successfully.
August 4: First set of beautiful images of the Earth captured by Chandrayaan-2 Vikram Lander.
August 6: The fifth earth bound orbit raising manoeuvre performed successfully.
August 14: The final orbit raising manoeuvre performed and Chandrayaan-2 enters Lunar Transfer Trajectory.
August 20: Lunar Orbit Insertion (LOI) manoeuvre
completed successfully. Chandrayaan-2
successfully inserted into a Lunar orbit. The orbit achieved is 114 km x 18072
At a press meet organised at ISRO Headquarters, Bengaluru, Dr. K Sivan, Chairman, ISRO,said, “the satellite is currently located in a lunar orbit with a distance of about 114 km at perilune (nearest point to the Moon) and 18,072 km at apolune (farthest point to the Moon).”He explained the details of the mission as follows: Till September 1, 2019, a series of four orbit manoeuvresare to be performed on Chandrayaan-2spacecraft to enable it to enter its final orbit passing over the lunar poles at a distance of about 100 km from the Moon’s surface.
Subsequently, on September 2, the Vikram lander will separate from the Orbiter. Following this, orbit manoeuvres will be performed on Vikram to place it in a 100 km X 30 km orbit around the Moon. Vikram will perform a series of complex braking manoeuvres to soft land in the South polar region of the Moon between two craters, Manzinus C and Simpelius N on September 7, 2019. A few hours later, the Rover Pragyaan will roll down from Vikram and will perform in situ exploration of the surrounding lunar surface.
August 21:Second Lunar bound orbit manoeuvre for Chandrayaan-2 spacecraft performed successfully, using the onboard propulsion system.
August 26: It was revealed that Lunar surface was imaged by Terrain Mapping Camera 2 (TMC-2) on August 23, 2019 at an altitude of ~4375 km showing impact craters such as Jackson, Mitra, Mach and Korolev.
Jackson is an impact crater located in the northern hemisphere of the far side of the Moon. It is a 71 km diameter crater at 22.4°N and 163.1°W . The interesting feature at the western outer rim of Mach crater is another impact crater, Mitra (92 km diameter). It is named after Prof. Sisir Kumar Mitra, who was an Indian physicist and Padma Bhushan recipient, known for his pioneering work in the field of ionosphere and Radiophysics. The Korolev crater is a 437 km crater which has several small craters of varying size.
August 28: The third Lunar Orbit manoeuvre performed successfully.
August 30: The fourth Lunar bound orbit manoeuvre performed successfully.
September 1: The final and fifth Lunar bound orbit manoeuvre performed successfully. The orbit achieved is 119 km x 127 km.
The next operation is the separation of Vikram Lander from Chandrayaan-2 Orbiter, scheduled on September 02. Following this, there will be two deorbit manoeuvres of Vikram Lander to prepare for its landing in the south polar region of the moon. The powered descent is to take place on September 7, 2019.
September 2: The Vikram Lander successfully separates from Chandrayaan-2 Orbiter. The Vikram Lander is located in an orbit of 119 km x 127 km. The Chandrayaan-2 Orbiter continues to orbit the Moon in its existing orbit. The health of the Orbiter and Lander is being monitored from the Mission Operations Complex (MOX) at ISRO Telemetry, Tracking and Command Network (ISTRAC) in Bengaluru with support from Indian Deep Space Network (IDSN) antennas at Bylalu, near Bengaluru
The soft landing of Chandrayaan-2 Vikram lander on lunar surface is scheduled between 1:30 am to 2:30 am on September 07. This will be followed by the Rover rollout between 5:30 am to 6:30 am.
September 3:Thefirst de-orbiting manoeuvre for Chandrayaan-2 performed successfully.
September 4: The second de-orbiting manoeuvre for Chandrayaan-2 spacecraft was performed successfully.
September 7: The Vikram Lander followed the planned descent trajectory from its orbit of 35 km to just below 2 km above the surface. All the systems and sensors of the Lander functioned excellently until this point.
Chandrayaan-2 mission was a highly complex mission, which represented a significant technological leap compared to the previous missions of ISRO, which brought together an Orbiter, Lander and Rover to explore the unexplored south pole of the Moon. The Chandrayaan-2 mission aimed at studying not just one area of the Moon but all the areas combining the exosphere, the surface as well as the sub-surface of the moon. The Orbiter has already been placed in its intended orbit around the Moon and shall perform the task of mapping of the minerals and water molecules in the Polar Regions.