Chandrayaan-3

Subject: Science and Technology

Context- chandrayaan-3 launch in June, ISRO

Chandrayaan-3 Mission-

The Chandrayaan-3 mission is a follow-up of Chandrayaan-2 of July 2019, which aimed to land a rover on the lunar South Pole.
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 2024.
It will have an orbiter and a landing module. However, this orbiter won’t be loaded with scientific instruments like the Chandrayaan-2.
- Its job will only be confined to carrying the lander to the moon, overseeing the landing from its orbit and communicating between the lander and the earth station.”

Chandrayaan-2 Mission-

Chandrayaan-2 consisted of an Orbiter, Lander and Rover, all equipped with scientific instruments to study the moon.
- The Orbiter would watch the moon from a 100-km orbit, while the Lander and Rover modules were to be separated to make a soft landing on the moon’s surface.
- ISRO had named the Lander module Vikram, after Vikram Sarabhai, the pioneer of India’s space programme, and the Rover module after Pragyaan, meaning wisdom.
It was sent aboard the country’s most powerful geosynchronous launch vehicle, the GSLV-Mk 3.
However, lander Vikram, instead of a controlled landing, ended up crash-landing and prevented rover Pragyaan from successfully travelling on the surface of the moon.

Information gathered by Chnadryaan-2-

Presence of water molecules on moon:
- The mission has given the most precise information about the presence of H2O molecules on the Moon till date.
Presence of Minor elements:
- Chromium, manganese and Sodium have been detected for the first time through remote sensing.
- The finding can lay the path for understanding magmatic evolution on the Moon and deeper insights into the nebular conditions as well as planetary differentiation.
Information about solar flares:
- A large number of microflares outside the active region have been observed for the first time, and according to ISRO, this “has great implications on the understanding of the mechanism behind heating of the solar corona”, which has been an open problem for many decades.
- Exploration of the permanently shadowed regions as well as craters and boulders underneath the regolith, the loose deposit comprising the top surface extending up to 3-4m in depth. This is expected to help scientists to zero in on future landing and drilling sites, including for human missions.

GSLV-Mk 3-

Geosynchronous Satellite Launch Vehicle Mark-III was developed by Indian Space Research Organisation (ISRO), is a three-stage vehicle, designed to launch communication satellites into geostationary orbit.
It has a mass of 640 tonnes that can accommodate up to 8,000 kg payload to Low Earth Orbit (LEO) and 4000 kg payload to GTO (Geo-Synchronous Transfer Orbit).

Why was the Lunar South Pole targeted for exploration?

The Lunar South pole is especially interesting because the lunar surface area that remains in shadow is much larger than that at the North Pole.
There could be a possibility of the presence of water in permanently shadowed areas around it.
In addition, the South Pole region has craters that are cold traps and contain a fossil record of the early Solar System.