Bangalore:
ISRO said the propulsion module (PM) of Chandrayaan-3 was moved from lunar orbit to Earth orbit, calling the operation a unique experiment.
The primary objective of the Chandrayaan-3 mission was to demonstrate a soft landing near the lunar south pole region and conduct experiments using instruments from the lander Vikram and the Pragyan spacecraft.
The spacecraft was launched on July 14, 2023 aboard an LVM3-M4 rocket at the Satish Dhawan Space Center (SDSC-SHAR).
Chandrayaan-3 Mission:
Ch-3’s propulsion module (PM) has successfully detoured!
In another unique experiment, PM is transported from lunar orbit to Earth orbit.
An orbital lift maneuver and a cross-Earth injection maneuver placed the PM in an Earth-bound orbit. pic.twitter.com/qGNBhXrwff
— Isro (@isro) December 5, 2023
On August 23, the Vikram lander made a historic lunar landing, followed by the deployment of the Pragyan rover.
The lander and rover’s scientific instruments operated continuously for one lunar day, according to the defined mission duration.
“The mission objectives of Chandrayaan-3 have been fully achieved,” the Indian Space Research Organization (ISRO) said in a statement.
The main purpose of the propulsion module was to transport the lander module from geostationary transfer orbit (GTO) to the final polar orbit around the moon and to separate the lander.
After separation, the Spectroscopic Polarimetry (SHAPE) payload inside the PM was also activated, the space agency said.
The original plan was to operate this payload for approximately three months during the PM mission. Precise orbital injection and optimal Earth or lunar combustion operations by LVM3 made more than 100 kg of fuel available for the PM after more than a month of operation in lunar orbit, it added.
ISRO said it has been decided to use the fuel available in the PM to derive additional information for future lunar exploration missions and demonstrate mission operations strategies for sample return missions.
It was decided to reorbit the PM into a suitable Earth orbit to continue the SHAPE payload for Earth observation. According to the statement, the mission plan includes preventing the PM from colliding with the lunar surface or entering Earth’s geostationary equatorial orbit (GEO) zone at an altitude of 36,000 km or below. It is said that it was formulated with avoidance in mind.
The optimal Earth return trajectory was designed in October 2023, considering the estimated availability of fuel and the safety of the GEO spacecraft.
The first maneuver was conducted on October 9, 2023, increasing Apollon’s altitude from 150 km to 5,112 km and extending its orbital period from 2.1 hours to 7.2 hours. The second maneuver plan was then revised to target her 1.8 million km x 3.8 million km Earth orbit, taking into account estimates of available propellant.
The Trans-Earth Injection (TEI) maneuver was conducted on October 13, 2023. During the post-TEI maneuver realization trajectory, the Prime Minister conducted four lunar flybys before departing the lunar sphere of influence (SOI) on November 10.
PM is currently orbiting the Earth and passed its first perigee on November 22 at an altitude of 1.54 million km. The orbital period is approximately 13 days, and the orbital inclination is 27 degrees. ISRO said the perigee and apogee altitudes will change during the orbit, and the minimum expected perigee altitude is 1.15 million km.
“Therefore, based on the current trajectory predictions, there is no risk of it approaching operational Earth-orbiting satellites,” the ministry said.
Per the plan, the SHAPE payload is operational whenever Earth is in view. Also, a special operation of the SHAPE payload was performed on his October 28, 2023 during a solar eclipse. SHAPE payload operations will continue, the statement added.
“The flight dynamics team at UR Rao Satellite Center/ISRO has developed ab initio analysis tools for this operation, which have been validated through return maneuvers conducted on Chandrayaan-3 PM,” ISRO said. said.
According to ISRO, the key outcomes of the repatriation exercise conducted at PM in connection with future missions are: Plan and execute orbits and exercises for returning to Earth from the Moon. Development of software modules for planning such operations and their preliminary validation. Planning and executing gravity-assisted flybys across planets or celestial bodies. And it avoids uncontrolled impact of the PM on the lunar surface at the end of the PM’s life and meets the requirement of not producing debris.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)