After orbit-lowering, Chandrayaan closer to Moon

After orbit-lowering, Chandrayaan closer to Moon

An artist's impression of the Chandrayaan-2's Orbiter-Lander-Rover composite orbiting over the lunar surface. Image: ISRO

Now firmly entrenched in a lunar orbit, Chandrayaan-2 got a bit more closer to the Moon’s surface on Wednesday afternoon with a successful second orbit maneouvre. This was performed at 12.50 pm as planned, using the spacecraft’s onboard propulsion system.

The maneouvre lasted 1,228 seconds (about 21 minutes). The Indian Space Research Organisation (Isro) declared that all the spacecraft parameters are normal. The new orbit achieved, closer to the lunar surface, is 118 km X 4,412 km.

The space agency has scheduled the next lunar-bound orbit maneouvre of the spacecraft for August 28 between 5.30 am and 6.30 am. Following Tuesday’s Lunar Orbit Insertion and Monday’s lowering, the mission will undergo three more orbit-lowering operations on August 28, 30 and September 1.

Once the Lander, Vikram separates from the Orbiter on September 2, Retro De-Orbit maneouvre is planned to ensure that no damage has been caused to the onboard instruments. This would be a preparation to get the Lander eventually on autonomous mode, away from the remote control of mission engineers.

But the most anticipated Chandrayaan-2 operation is the Lander’s final powered descent onto the lunar surface on September 7, beginning at 1.40 am. If all goes well, Vikram will touchdown at 1.55 am in the lunar south polar region, recording a landmark achievement for India and Isro.

Meanwhile, space buffs are eagerly awaiting the first
photographs of the lunar surface taken by the mission’s onboard cameras. Isro has so far only released an artist’s impression of the Orbiter-Lander-Rover composite orbiting the Moon.

The real images would be critical to analyse and identify a flat surface for Vikram to land and the Rover, Pragyan to roll out for a closer probe. The first maps of the landing site are expected to emerge by September 4.

Isro Chairman K Sivan had on Tuesday informed that the landing surface had to be flat with a slope of less than 12 degrees. Anything beyond that would force the Lander to topple over.