Launch

Chandrayaan-2 lifting off on 22 July 2019 at 02.43 PM IST

The launch of Chandrayaan-2 was initially scheduled for 14 July 2019, 21:21 UTC (15 July 2019 at 02:51 IST local time). However, the launch was aborted 56 minutes and 24 seconds before launch due to a technical glitch, so it was rescheduled to 22 July 2019. Unconfirmed reports later cited a leak in the nipple joint of a helium gas bottle as the cause of ancellation.

Finally Chandrayaan-2 was launched on board the GSLV MK III M1 launch vehicle on 22 July 2019 at 09:13 UTC (14:43 IST) with a better-than-expected apogee as a result of the cryogenic upper stage being burned to depletion, which later eliminated the need for one of the apogee-raising burns during the geocentric phase of mission. This also resulted in the saving of around 40 kg fuel on board the spacecraft.

Immediately after launch, multiple observations of a slow-moving bright object over Australia were made, which could be related to upper stage venting of residual LOX / LH2 propellant after the main burn.

Geocentric phase

After being placed into a 45,475 × 169 km parking orbit by the launch vehicle,^[33] the Chandrayaan-2 spacecraft stack gradually raised its orbit using on-board propulsion over 22 days. In this phase, one perigee-raising and five apogee-raising burns were performed to reach a highly eccentric orbit of 142,975 × 276 km^[120] followed by trans-lunar injection on 13 August 2019.^[121] Such a long Earth-bound phase with multiple orbit-raising manoeuvres exploiting the Oberth effect was required because of the limited lifting capacity of the launch vehicle and thrust of the spacecraft's on-board propulsion system. A similar strategy was used for Chandrayaan-1 and the Mars Orbiter Mission during their Earth-bound phase trajectory. On 3 August 2019, the first set of Earth images were captured by the LI4 camera on the Vikram lander, showing the North American landmass.

Selenocentric Phase

After 29 days from its launch, the Chandrayaan-2 spacecraft stack entered lunar orbit on 20 August 2019 after performing a lunar orbit insertion burn for 28 minutes 57 seconds. The three-spacecraft stack was placed into an elliptical orbit that passed over the polar regions of the Moon, with 18,072 km (11,229 mi) aposelene and 114 km (71 mi) periselene. By 1 September 2019, this elliptical orbit was made nearly circular with 127 km (79 mi) aposelene and 119 km (74 mi) periselene after four orbit-lowering manoeuvres followed by separation of Vikram lander from the orbiter on 07:45 UTC, 2 September 2019.

Planned Landing Site

Landing site [130]	Coordinates
Prime landing site	70.90267°S 22.78110°E
Alternate landing site	67.87406°S 18.46947°W

 

The flat highland between craters Manzinus C and Simpelius N was the planned landing zone for the Vikram lander.

Two landing sites were selected, each with an ellipse of 32 km × 11 km (19.9 mi × 6.8 mi). The prime landing site (PLS54) was at 70.90267°S 22.78110°E (600 km (370 mi) from the south pole,) and the alternate landing site (ALS01) was at 67.87406° South 18.46947° West. The prime site was on a high plain between the craters Manzinus C and Simpelius N, on the near side of the Moon.

Source: https://en.wikipedia.org/wiki/Chandrayaan-2#Launch