Chandrayaan Missions of India – Part 2

(இதன் தமிழ் வடிவத்திற்கு இங்கே கொடுக்கவும்)

Chandrayaan 2

• Chandrayaan – 2 is the second lunar mission of India after the success of Chandrayaan 1.
• Chandrayaan-2 is India’s first Lander mission.
• This mission was conducted for topographical researches and mineralogical studies to have a better understanding of the Moon’s origin and evolution.
• It consists of an Orbiter, Lander and Rover.
• It is all equipped with scientific instruments to study the moon.
• The Lander and Rover modules will separate from the orbiter.
• It is makes a soft-landing on moon’s surface (either on September 5 or 6, 2019).
• The Lander and rover are designed to work for only 14 days (1 lunar day).
• While the orbiter would remain in orbit for a year.

Chandrayaan-2: Design and Mission Profile

Orbiter  

• The Orbiter would once again watch the moon from a 100-km orbit.
• The Orbiter is a 2379-kg spacecraft with 7 instruments on board.
• It is equipped with different kinds of cameras to take high-resolution three-dimensional maps of the surface.
• It also has instruments to study the mineral composition on the moon.
• It is to assess the lunar atmosphere and to the abundance of water.
• The Orbiter will observe lunar surface.
• It is to relay communication between Earth and the Lander.

Lander 

• ISRO has named the Lander module as Vikram, after Vikram Sarabhai.
• He was the pioneer of India’s space programme.
• The 1471-kg lander will remain stationary after touching down on the moon’s surface.

• It will carry three instruments that will mainly study the moon’s atmosphere.
• One of the instruments will also look out for seismic activity on lunar surface.

Rover  

• The Rover is a 6-wheeled, Artificial Intelligence-powered.
• It is solar-powered vehicle named Pragyan.  
• Pragyan means wisdom.
• Once on the moon, the rover will detach itself from the Lander.
• Equipped with two instruments, it would slowly crawl on the surface.
• It is making observations and collecting data.

• Its primary objective is to study the composition of the moon’s surface near the landing site.
• It would also determine the abundance of different elements on the moon’s surface.
• It was planned to land on the South Pole of the Moon, Chandrayaan-2.
• It was launched on 22th July in 2019.
• However, the lander Vikram hard-landed on 7th September 2019.
• ISRO recently announced the launch date (July 15, 2019) of Chandrayaan-3 mission.
• It was after the long delay from the scheduled launch.
• All of the above parts were developed in India.
• The orbiter, lander and rover collectively carried 14 scientific payloads.
• It was including a Laser Retro Reflector Array from NASA that provided precise measurements of the distance between the Moon and the Earth.

What are Chandrayaan-2’s features?

• The same kind of information was also obtained by NASA's Deep Impact-EPOXI mission.
• EPOXI mission passed near the Moon in June 2009.
• On 22 July 2019, India launched Chandrayaan-2.
• It is second lunar exploration mission after Chandrayaan-1 from Satish Dhawan Space Centre, Sriharikota.
• It is a Lunar orbiter, lander, rover type mission.
• It is expected to do soft-landing on the Moon on 7 September, 2019.
• Chandrayaan-2 is ISRO’s first attempt to land on any extraterrestrial surface.

Core Objective

• It aims to map the location, and abundance of lunar water.

Background

• The project began in 2007 with an agreement between India’s space agency ISRO and Russia’s ROSCOSMOS for mutual cooperation.
• However, the mission was postponed in January 2013.
• It was rescheduled to 2016 as Russia was unable to develop the lander on time.
• Later, after Russia’s withdrawal, India decided to develop the lunar mission independently.
• Finally, on 22 July 2019, GSLV MK III M1 on its first operational flight successfully launched Chandrayaan-2.
• Once successful, India will become the fourth country to soft-land a spacecraft on the Moon after the USSR, the USA and China.
• Chandrayaan-2 will make a landing at a site where no earlier mission has gone.
• It will be near the south pole of the Moon.
• Chandrayaan-2 is a natural sequel to Chandrayaan-1.
• It was an Orbiter mission launched in October 2008.

Mission Objectives

• India wanted to study the southern pole of the lunar surface.
• No country in the world has ever launched its spacecraft on the southern side of the Moon.
• The main objectives of the mission were as follows:
• To find the existence of water and the Hydroxyl group.

• To study the topology and exosphere of the Moon.
• To study the mineralogy, surface chemical structure, the lunar atmosphere.
• To study the origin and evolution of the Moon and thermo-physical elements.
• To Create a three-dimensional (3D) map of the lunar surface.
• To Try and build on the evidence of water molecules shown by Chandrayaan-I.
• To study the extent and distribution of water on the Moon
• To study the ancient rocks and craters.
• The Chandrayaan 2 components were designed to measure the thickness of the lunar regolith.
• India independently designed all the Chandrayaan 2 components.
• It wanted to experiment with soft landing on the lunar surface.
• It can offer indications of origin and evolution of the Moon.
• The South Pole region of the Moon also contains clues to the fossil records of early solar system.
• Thus, it will improve our understanding of the early solar system.
• It will Map the lunar surface and prepare 3D maps of it.

Mission Challenges

• Chandrayaan 2 is a technologically challenging mission.
• It requires the multifaceted developments of various new systems for the first time.
• The Lander is the distinguishing feature.
• As it is the first time that ISRO is attempting to soft-land a module in extra-terrestrial space.
• Once the Lander and the Rover, enter the Moon’s gravity, they would be in a state of free fall.
• That could end in crash-landing and destruction of instrument.
• The main challenge is thus in controlling its speed as it approaches the surface.
• To enable a smooth landing, the speed of the Lander just ahead of touchdown should be 1 m/s (3.6 km/h) or less.
• Due to lack of air to provide drag, these instruments cannot make use of parachute-like technologies.
• So instead, the Lander fires thrusters in the opposite direction to slow down.
• It requires a very high level of perfection.

Major challenges in the complete mission involve:

• Successfully performing the launch of its heaviest rocket GSLV-Mark III.
• Ensuring trajectory accuracy while travelling such a long distance.
• It will perform successive orbital manoeuvres to raise the module into higher orbits.
• It will perform Until it reaches the “Earth to Moon” transfer orbit.

Landing on safe hazard free zone

• ISRO had never performed soft landing on any space object.
• The lunar surface is covered with craters, rocks, dust, hot gases.
• It faces extreme surface temperature variations.
• Thus, it is an extremely hostile environment for Lander and rover operations.
• Further, the South Pole region of the Moon receives less sunlight compared to equatorial region.
• The equatorial region is required by solar-powered instruments.
• Thus, the margin of error is extremely narrow.
• The recent failure of Israel’s Moon landing mission indicates the difficulty in soft and precise moon landing.

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