Chandrayaan 3 : A journey to the Moon

by Yogi P - August 19, 2023

Chandrayaan 3

Think of Chandrayaan 3 as India’s next step in exploring our closest neighbor in space, the Moon. This mission is the sibling of Chandrayaan 2, aiming to show that India can safely land a spacecraft on the Moon and have it take a little stroll there (that’s the “roving” part).

Chandrayaan 3 Mission

Chandrayaan 3, India’s third lunar exploration mission is ready to take off in fourth operational mission (M4) of LVM3 launcher. ISRO is crossing new frontiers by demonstrating soft landing on lunar surface by its lunar module and demonstrate roving on the lunar terrain. It is expected to be supportive to ISRO’s future interplanetary missions. Additionally the deployment of rover and in-situ scientific experiment will scale new heights in lunar expeditions by deploying Rover. Yes, ISRO is bringing the Moon closer to us.

Mission sequence

The various mission phases are classified as follows:

1. Earth Centric Phase (Phase-1)

• Pre-launch Phase
• Launch and Ascent Phase
• Earth-bound Manoeuvre Phase

2. Lunar Transfer Phase (Phase-2)

• Transfer Trajectory Phase

3. Moon Centric Phase

• Lunar Orbit Insertion Phase (LOI)-(Phase-3)
• Moon-bound Manoeuvre Phase (Phase-4)
• PM and Lunar Module Separation (Phase-5)
• De-boost Phase (Phase-6)
• Pre-landing Phase (Phase-7)
• Landing Phase (Phase-8)
• Normal Phase for Lander and Rover (Phase-9)
• Moon Centric Normal Orbit Phase (100 km circular orbit) – For Propulsion Module (Phase-10)

Propulsion Module

Chandrayaan 3 consists of an indigenous propulsion module, lander module, and a rover with an objective of developing and demonstrating new technologies required for inter-planetary missions.

The propulsion module will carry the lander and rover from injection orbit to till 100 km lunar orbit. It also carries a Spectro-polarimetry of Habitable Planetary Earth (SHAPE) payload to study the spectral and polarimetric measurements of earth from the lunar orbit.

The main function of Propulsion Module is to carry the LM from launch vehicle injection orbit to till Lander separation.

LMV3

LVM3 is the operational heavy lift launch vehicle of ISRO and has a spectacular pedigree of completing 6 consecutive successful missions. This is the 4th operational flight of LVM3, aims to launch the Chandrayaan-3 spacecraft to Geo Transfer Orbit (GTO).

LVM3 has proved its versatility to undertake most complex missions like:

• Injecting multi-satellites
• Mission planning to ensure safe relative distance among separated satellites through re-orientation and velocity addition maneuvers.
• Multi orbit (LEO, MEO, GEO) and execute interplanetary missions.
• India’s largest and heaviest launch vehicle ferrying indian and international customer satellites.

LVM3-M4 will be launched from the Second Launch Pad (SLP), SDSC, SHAR

Here’s the game plan:

The Journey Begins: The Chandrayaan 3 mission is being launched by a mighty rocket called LVM3. It’s set to lift off from Sriharikota, a spaceport in India.

A Guiding Star: Once launched, the Propulsion Module (think of it as the spacecraft’s engine room) will guide the Lander and Rover, essentially giving them a lift, until they’re just 100 km away from the Moon.

Eyes on Home: The Propulsion Module isn’t just a workhorse; it’s also got a keen eye. It carries a special tool called SHAPE, which will be studying Earth from the Moon’s orbit, like a sailor uses a telescope to see the shore from the sea.

Once the spacecraft is near the Moon:

Touchdown: The Lander, aptly equipped with cutting-edge technology, aims to perform a “soft landing”, which is space talk for landing smoothly and not crashing. Imagine it like landing a plane gently and with precision on a runway.

To help it land as safe as houses, it has Laser and RF based Altimeters (to measure height), Doppler Velocimeters (to measure speed), and special cameras and algorithms to spot and avoid any dangerous rocks or slopes.

Science Time: After the landing, it’s not just going to sit and twiddle its thumbs. The Lander has its own set of scientific tools, including:

• ChaSTE, which will act like the Moon’s doctor, checking its ‘temperature’ and ‘thermal pulse’.
• ILSA to detect ‘moonquakes’, which are like earthquakes but on the Moon.
• LP to estimate the density of plasma (charged particles) around the Moon.

A bonus item from NASA, a passive Laser Retroreflector Array, for special laser experiments. Think of this as a friendly nod between scientists from across the globe.

Moonwalk: The Rover, which is like the Lander’s pet robot, will then be deployed. It will explore the Moon’s surface like a detective on the beat, examining the soil and rocks.

The Rover is armed with its own set of investigative tools, APXS and LIBS, to analyze the elements found in the Moon’s soil, like a prospector panning for gold.

Testing, Testing: Before this grand journey, the team conducted several special tests on Earth, using helicopters, cranes, and special ‘moon-like’ test beds. This was to ensure that the Lander and Rover are ready to face the music, and can handle the conditions they’ll meet on the Moon.

And that’s Chandrayaan-3 for you! India’s way of shooting for the moon – quite literally – and exploring new frontiers in space. 🚀🌕

Reference:

https://www.isro.gov.in/media_isro/pdf/Missions/LVM3/LVM3M4_Chandrayaan3_brochure.pdf