CHADRAYAAN 3

 CHADRAYAAN 3 

The launch of Chandrayaan-3 took place on 14 July 2023, at 2:35 pm IST and the injection of a 100 km circular polar orbit was completed successfully as part of phase one. The lander and rover are expected to land near the lunar south pole region on 23 August 2023.

 Chandrayaan-3 is the third lunar exploration mission by the Indian Space Research Organisation (ISRO). It consists of a lander and the Pragyan rover similar to Chandrayaan-2, but does not have an orbiter. Its propulsion module behaves like a communication relay satellite. The propulsion module carries the lander and rover configuration until the spacecraft is in a 100 km lunar orbit.

Following Chandrayaan-2, where a last-minute glitch in the landing guidance software led to the lander crashing after entering lunar orbit, another lunar mission was proposed.

The launch of Chandrayaan-3 took place on 14 July 2023, at 2:35 pm IST  and the injection of a 100 km circular polar orbit was completed successfully as part of phase one. The lander and rover are expected to land near the lunar south pole region on 23 August 2023.

Background

In the second phase of the Chandrayaan program to demonstrate a soft landing on the Moon, ISRO launched Chandrayaan-2 on board a Launch Vehicle Mark-3 (LVM 3) launch vehicle consisting of an orbiter, a lander, and a rover. The lander was scheduled to touchdown on the lunar surface in September 2019 to deploy the Pragyan rover.

Earlier reports had emerged about a collaboration with Japan on a mission to the lunar south pole where India would be providing the lander while Japan would provide both launcher and rover. The mission may include site sampling and lunar night survival technologies.

The subsequent failure of the Vikram lander led to the pursuit of another mission to demonstrate the landing capabilities needed for the Lunar Polar Exploration Mission proposed in partnership with Japan for 2025. During mission-critical flight operations, the European Space Tracking (ESTRACK) operated by European Space Agency (ESA) will support the mission according to a contract.

Objective

ISRO has set three main objectives for the Chandrayaan-3 mission, which include:

1. Getting a lander safe and soft and perfect landing on the surface of the Moon.
2. Observing and demonstrating the rover’s loitering capabilities on the Moon
3. In-site scientific observation making scientific experiments on the chemical and natural elements, soil, water, etc. available on the surface of the Moon to better understand and practice the composition of the Moon. Interplanetary refers to the development and demonstration of new technologies required for missions between two planets.

Design

Chandrayaan-3 comprises three main components:

Propulsion Module:

The propulsion module will carry the lander and rover configuration till the 100 km lunar orbit. It is a box-like structure with one large solar panel mounted on one side and a large cylinder on top (the Intermodular Adapter Cone) that acts as a mounting structure for the lander. In addition to the lander, the module carries a payload called Spectro-polarimetry of Habitable Planet Earth (SHAPE) to study the spectral and polarimetric measurements of Earth from the lunar orbit.

Lander

The lander is responsible for the soft landing on the Moon. It is also box-shaped, with four landing legs and four landing thrusters of 800 newtons each. It will carry the rover and various scientific instruments to perform in-site analysis.

The lander for Chandrayaan-3 will have only four throttle-able engines, unlike Vikram on Chandrayaan-2 which had five 800 Newtons engines with a fifth one being centrally mounted with a fixed thrust. Additionally, the Chandrayaan-3 lander will be equipped with a Laser Doppler Velocimeter (LDV). The impact legs are made stronger compared to Chandrayaan-2 and increased instrumentation redundancy. ISRO is working on improving the structural rigidity and adding multiple contingency systems.

The lander will carry three payloads:

• Chandra's Surface Thermophysical Experiment (ChaSTE) will measure the thermal conductivity and temperature of the lunar surface.
• Instrument for Lunar Seismic Activity (ILSA) will measure the seismicity around the landing site.
• Langmuir Probe (LP) will estimate the plasma density and its variations.

Rover:

Chandrayaan-3 Rover Overview:

• Six-wheeled design
• Weight of 26 kilograms (57 pounds)
• Range of 500 meters (1,640 feet)
• Scientific instruments including cameras, spectrometers, and a drill
• Expected lifespan of one lunar day (14 Earth days)
• Communication with the lander and ground control team in India

The Chandrayaan-3 Rover is expected to make several important scientific discoveries, including:

• The composition of the lunar surface
• The presence of water ice in the lunar soil
• The history of lunar impacts
• The evolution of the Moon’s atmosphere

The Chandrayaan-3 Rover is a major step forward for India’s space program. It is a testament to the country’s growing technological capabilities, and it is sure to make significant contributions to our understanding of the Moon.