Chandrayaan-3 Closer to Moon Landing; How Propulsive Manoeuvre Came into Play & What's Next | Explained

India’s third lunar mission Chandrayaan-3 has completed its orbits around the Earth and is now heading towards the Moon after successfully injected into the translunar orbit.

The Indian Space Research Organisation (ISRO) on August 1 performed the Trans Lunar Injection (TLI), a propulsive manoeuvre to slingshot the spacecraft towards the Moon from Earth’s orbit.

Chandrayaan-3 was launched on July 14 into an orbit around Earth and has been slowly boosting its orbit ahead of a final shot toward the moon. Here is all you need to know the current phase of India’s lunar mission and what to expect from Chandrayaan-3 in the coming days.

All About Chandrayaan’s Propulsive Manoeuvre

Chandrayaan-3 consists of three components- indigenous Lander module (LM), Propulsion module (PM) and a Rover which are used during different phases of the inter-planetary missions.

While the Lander has the capability to soft land at a specified lunar site and deploy the rover which to carry out research, the Propulsion module carry the lander from launch vehicle injection till final lunar 100 km circular polar orbit.

The Trans Lunar Injection which was conducted on Tuesday was a propulsive manoeuvre which sends the Chandrayaan on a trajectory that will set it towards the Moon.

In other words, the propulsive manoeuvre put Chandrayaan-3 in a translunar orbit moving it out of the Earth’s orbit and closing in on the Moon’s orbit. In around five days from now, the spacecraft will reach the Moon’s orbit.

This process included a significant burn, done by a chemical rocket engine, which surged the spacecraft’s velocity. The increased velocity changes the spacecraft’s orbit from a circular low Earth orbit to a highly eccentric one, thus getting closed to Moon’s orbit. According to ISRO, the Lunar-Orbit Insertion is now planned for August 5.

What Happens Next?

Chandrayaan-3 has completed its orbits around the Earth and will now head towards the Moon. The spacecraft has begun its journey towards the Moon on Tuesday as the TLI manoeuvre placed it on ‘lunar transfer trajectory’.

The Chandrayaan-3 is expected to reach the lunar orbit on August 5 and the spacecraft’s liquid engine will be fired again to insert the spacecraft into a lunar orbit.

The Chandrayaan will then orbit the moon four times and get closer to the lunar surface with each loop. Once the craft is in the lunar orbit, the Lander will separate from the Propulsion Module and attempt a soft landing near the South Pole of the moon on August 23 evening at 5.47 pm.

After a successful touchdown, the mission lander and rover will collect data on the surface of the moon for up to 14 Earth days.

What Data will Chandrayaan-3 Collect?

The propulsion module as explained earlier is equipped with the Spectro-polarimetry of Habitable Planet Earth (SHAPE) payload, which is designed to conduct spectral and polarimetric measurements of Earth from the lunar orbit.

This payload will provide valuable data and insights into the Earth’s characteristics and habitability from a unique vantage point on the Moon.

The lunar mission aims to explore the Moon’s surface, particularly areas that have been deprived of sunlight for billions of years. The exploration will not be limited to the surface but will also focus on studying the sub-surface and exosphere, as per reports.