History of Chandrayaan

India on Moon

Discovering Bharat

The Chandrayaan missions are a series of Indian lunar exploration missions conducted by the Indian Space Research Organisation (ISRO) with a Dream of touching the Moon. These missions have been designed to explore the Moon's surface, study its mineral composition, and understand its geological and topographical features.

  1. Chandrayaan 1: The Chandrayaan-1 mission was launched on October 22, 2008, and the spacecraft entered lunar orbit on November 8. Six days later, the Moon Impact Probe, which had the Indian colours on its sides, was made to crash land on the lunar surface — to leave India's mark on the Moon. It was India's first attempt to reach the Moon and had a budget of Rs 386 crore. It was also known as India's budget mission to the Moon. It was one of major milestones in India's space programme.

  1. Chandrayaan 2: Chandrayaan-2 is India's second lunar exploration mission and was launched on July 22, 2019. It consisted of three components: the orbiter, the lander named Vikram, and the rover named Pragyan to explore the unexplored South Pole of the Moon.T On August 20, 2019, Chandrayaan-2 was successfully inserted into lunar orbit. While orbiting the moon in a 100 km lunar polar orbit, on September 02, 2019, Vikram Lander was separated from the Orbiter in preparation for landing. Subsequently, two de-orbit maneuvers were performed on Vikram Lander so as to change its orbit and begin circling the moon in a 100 km x 35 km orbit. Vikram Lander descent was as planned and normal performance was observed upto an altitude of 2.1 km. Subsequently communication from lander to the ground stations was lost. The orbiter continues to study the Moon from orbit, providing valuable data about its surface and composition. The Chandrayaan-2 mission cost India Rs 978 crore.

  1. Chandrayaan 3: India has created history as it became the first country to land on the South Pole of lunar surface. PM Modi congratulated Indians and space scientists for the achievement. ‘India will remember this day forever’ PM Modi said. Chandrayaan-3 was launched on 14 July 2023. The lander and rover landed at the lunar south pole region on 23 August 2023 at 18:04 IST, making India the first country to successfully land a spacecraft near the lunar south pole and the fourth country to soft-land on the Moon.

    Chandrayaan-3 is a follow-on mission to Chandrayaan-2 to demonstrate end-to-end capability in safe landing and roving on the lunar surface. It consists of Lander and Rover configuration. It was be launched by LVM3 from SDSC SHAR, Sriharikota.

    Lander payloads: Chandra’s Surface Thermophysical Experiment (ChaSTE) to measure the thermal conductivity and temperature; Instrument for Lunar Seismic Activity (ILSA) for measuring the seismicity around the landing site; Langmuir Probe (LP) to estimate the plasma density and its variations. A passive Laser Retroreflector Array from NASA is accommodated for lunar laser ranging studies.

    Rover payloads: Alpha Particle X-ray Spectrometer (APXS) and Laser Induced Breakdown Spectroscope (LIBS) for deriving the elemental composition in the vicinity of landing site.

Chandrayaan-3 consists of an indigenous Lander module (LM), Propulsion module (PM) and a Rover with an objective of developing and demonstrating new technologies required for Inter planetary missions. The Lander will have the capability to soft land at a specified lunar site and deploy the Rover which will carry out in-situ chemical analysis of the lunar surface during the course of its mobility. The Lander and the Rover have scientific payloads to carry out experiments on the lunar surface. The main function of PM is to carry the LM from launch vehicle injection till final lunar 100 km circular polar orbit and separate the LM from PM. Apart from this, the Propulsion Module also has one scientific payload as a value addition which will be operated post separation of Lander Module. The launcher identified for Chandrayaan-3 is LVM3 M4 which will place the integrated module in an Elliptic Parking Orbit (EPO) of size ~170 x 36500 km.

The mission objectives of Chandrayaan-3 are:

  1. To demonstrate Safe and Soft Landing on Lunar Surface

  2. To demonstrate Rover roving on the moon and

  3. To conduct in-situ scientific experiments.

To achieve the mission objectives, several advanced technologies are present in Lander such as,

  1. Altimeters: Laser & RF based Altimeters

  2. Velocimeters: Laser Doppler Velocimeter & Lander Horizontal Velocity Camera

  3. Inertial Measurement: Laser Gyro based Inertial referencing and Accelerometer package

  4. Propulsion System: 800N Throttleable Liquid Engines, 58N attitude thrusters & Throttleable Engine Control Electronics

  5. Navigation, Guidance & Control (NGC): Powered Descent Trajectory design and associate software elements

  6. Hazard Detection and Avoidance: Lander Hazard Detection & Avoidance Camera and Processing Algorithm

  7. Landing Leg Mechanism.

To demonstrate the above said advanced technologies in earth condition, several Lander special tests have been planned and carried out successfully viz.

  1. Integrated Cold Test - For the demonstration of Integrated Sensors & Navigation performance test using helicopter as test platform

  2. Integrated Hot test – For the demonstration of closed loop performance test with sensors, actuators and NGC using Tower crane as test platform

  3. Lander Leg mechanism performance test on a lunar simulant test bed simulating different touch down conditions.

The precise budget for Chandrayaan-3 is set at Rs. 615 crore. This is notably lower than the Chandrayaan-2 budget, indicating a consistent effort by ISRO to enhance efficiency and reduce costs. The allocated budget encompasses everything from the spacecraft and launch vehicle to the critical ground support facilities.