After the five Earth-bound maneuvers that had raised Chandrayaan-2’s orbit around Earth, the spacecraft has now entered a lunar transfer trajectory, that is, a trajectory that will carry it to the moon. The Indian Space Research Organisation (ISRO) performed the final maneuver yesterday (August 14, 2019) according to clocks in India. A statement from ISRO said:
The final orbit-raising maneuver of Chandrayaan-2 spacecraft was successfully carried out today … at 02:21 a.m. IST [21:00 UTC on August 13]. During this maneuver, the spacecraft’s liquid engine was fired for about 1,203 seconds. With this, Chandrayaan-2 entered the lunar transfer trajectory. Since its launch on July 22, 2019, by GSLV MkIII-M1 vehicle, all systems onboard Chandrayaan-2 spacecraft are performing normally.
This trajectory will take Chandrayaan-2 to the moon’s vicinity on August 20, 2019. Once there, the spacecraft’s engines will fire again, with the goal of inserting the craft into an orbit around the moon. Four orbit maneuvers are planned to decrease its orbit until it is about 60 miles (100 km) above the moon’s surface, at which point the mission’s Vikram lander will attempt to soft-land at the moon’s south pole.
Vikram carries a six-wheeled, solar-powered rover designed to travel 500 meters (about the length of five American football fields, end to end) to perform on-site chemical analysis for one lunar day (14 Earth days). Meanwhile, the orbiter, among other tasks, has the goal of providing a quantitative estimation of water content present at the moon’s poles. The orbiter is expected to last for one year.
August 20, 2019: Chandrayaan-2’s lunar insertion burn.
September 1, 2019: After the fifth burn, the desired orbit of 70 to 80 miles (114 x 128 km) around the moon is expected to be achieved.
September 2, 2019: The lander Vikram along with the rover Pragyan will separate and begin its descent towards the moon’s south pole.
Bottom line: The Chandrayaan-2 spacecraft has shifted trajectories and is now on its way to the moon.
Sharmila Kuthunur is a freelance science writer based in India. A computer engineer by profession, she found her love for astronomy in one of Carl Sagan's books - The Pale Blue Dot and has been hooked ever since. She has a fondness for old school astronomy and spends almost all of her free time either gazing up at the sky or reading about it. She is also the Contributor for Astronomy magazine since October 2017. She loves putting thoughts into words and talking about all things space.