Chandrayaan 2 nails third of five orbit-lowering manoeuvres before entering moon's orbit

From 2 September, all eyes will be on the lander, Dr Sivan said, much like a bridegroom on her wedding.


The second moon mission from India, Chandrayaan 2, has successfully carried out a series of orbit manueovres to lower its orbit around the moon for a third time, ISRO confirmed in a tweet. The lunar-bound manueovre was started at 9.04 am on 28 August using the onboard propulsion system, and lasted 1190 seconds. This third or five orbit-lowering manoeuvre gas placed Chandrayaan 2 in a 179km x 1411 km (nearest x farthest distance) elliptical orbit, and ISRO has said that all parameters of the spacecraft seem to be healthy.

The Chandrayaan 2 composite has carried out three successful in-orbit manueovres since it entered lunar orbit — all in an attempt to lower its altitude in preparation to land. The final orbit manueovre, planned for 6-7 pm IST on 30 August, will put Chandrayaan 2 on a path that passes over the lunar poles at a distance of about 100 km from the surface. Entering this circular orbit is the mission's final milestone before the Vikram lander separates from the orbiter to make its planned soft-landing on the moon's surface on 7 September.

Chandrayaan 2 nails third of five orbit-lowering manoeuvres before entering moons orbit

Chandrayaan-2 launch will kick off at 2:51 am on 15 July.

The spacecraft, which was earlier in an elliptical 118 x 4412 km (nearest x farthest distance) orbit around the moon before the successful manoeuvre is now in a 100 x 100 km circular orbit. This is close enough for the separation and landing sequences that are planned for 2 September and 7 September, respectively.

The next manoeuvre in lunar orbit is scheduled for 30 August, ISRO has said, following by the Vikram lander's pre-landing manueovres on 1 September and separation on 2 September. From 2nd September, all eyes will be on the lander, Dr Sivan said, much like a bridegroom on her wedding.

Orbit-raising diagram for the Chandrayaan 2 misson. Image: ISRO

Orbit-raising diagram for the Chandrayaan 2 misson. Image: ISRO

On 3 and 4 September, the first maps of the landing site will be created to ensure the landing site is as safe as previously thought to make a soft-landing. This is crucial since ISRO's mission engineers won't be operating the spacecraft remotely. This is an important part of the orbiter's mission: surveilling its year-long home for the first time, ensuring that no damage was caused to its instruments on the journey thus far, and a thorough examination of the Vikram lander's landing site at the moon's South Polar region.

Chandrayaan 2 is expected to make its long-awaited powered descent and landing on 7 September at 1.40 am IST in a landing sequence that the ISRO Chief describes as '15 minutes of terror'.

While subsequent events in the mission won't be streamed live, you can catch live updates on the mission on our dedicated Chandrayaan 2 domain, our Twitter pageISRO's website, or Twitter page.