9 Aug 2019

Chandrayaan -2

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Source: The Hindu

Manifest pedagogy:

ISRO is in full swing in terms of its back to back successful missions. It is not heeding to its failures. With the initial setback it bounced back to meet its self set deadline. Chandrayaan 2 again is one of its kind mission and it has set many firsts. Hence, Chandrayaan 2 is a very hot topic for both Prelims and Mains

In news:

  • Recently ISRO successfully raised Chandrayaan-2’s orbit for fifth time.

Placing it in syllabus:

  • Indigenisation of Science and technology 

Current dimensions:

  • Components of Chandrayaan- 2
  • Glimpse of Chandrayaan-1
  • Far side of the moon
  • South Pole of the moon 
  • Lunar missions of other countries 


On July 22, 2019 , the Chandrayaan-2 was injected into an elliptical orbit of 170×45,475km by India’s heavy lift rocket Geosynchronous Satellite Launch Vehicle-Mark III (GSLV Mk III). The ISRO has said the trans-lunar insertion of Chandrayaan-2, which will send it to the moon, is scheduled on August 14. After that, the Chandrayaan-2 is scheduled to reach the Moon by August 20 and the lander will land on the moon on September 7,2019.

Components of Chandrayaan-2:

Moon provides the best linkage to Earth’s early history. It offers an undisturbed historical record of the inner Solar system environment. Extensive mapping of the lunar surface to study variations in lunar surface composition is essential to trace back the origin and evolution of the Moon. 

       India has successfully launched the Chandrayaan-2 mission on July 22, 2019

It consists of a lunar orbiter, lander named Vikram and a lunar rover named Pragyan, all developed in India.The main scientific objective is to map the location and abundance of lunar water. 

Chandrayaan-2 is a follow-up mission from the Chandrayaan-1 mission that assisted in confirming the presence of water/hydroxyl on the moon in 2009. The orbiter will perform mapping from an altitude of 100 kilometers (62 miles), while the lander will make a soft landing on the surface in a high plain between two craters, Manzinus C and Simpelius N, at a latitude of about 70° south and send out the rover

What makes Chandrayaan 2 special?

  • 1st space mission to conduct a soft landing on the Moon’s south polar region.
  • 1st Indian expedition to attempt a soft landing on the lunar surface with home-grown technology.
  • 1st Indian mission to explore the lunar terrain with home-grown technology.
  • 4th country ever to soft land on the lunar surface

Science experiments

Chandrayaan-2 has several science payloads to expand the lunar scientific knowledge through detailed study of topography, seismography, mineral identification and distribution, surface chemical composition, thermo-physical characteristics of top soil and composition of the tenuous lunar atmosphere, leading to a new understanding of the origin and evolution of the Moon

  • For understanding of the Lunar composition, it is planned to identify the elements and mapping its distribution on the lunar surface both at global and In-situ level.
  • In addition detailed 3-dimensional mapping of the lunar regolith will be done. 
  • Measurements on the near surface plasma environment and electron density in the Lunar ionosphere will be studied. 
  • Thermo-physical property of the lunar surface and seismic activities will also be measured.
  • Water molecule distribution will be studied using infrared spectroscopy, synthetic aperture radiometry & polarimetry as well as mass spectroscopy techniques

Key payloads

  • Chandrayaan 2 Large Area Soft X-ray Spectrometer – for Elemental composition of the Moon
  • Imaging IR Spectrometer– for Mineralogy mapping and water-ice confirmation
  • Synthetic Aperture Radar (L & S Band) – for Polar-region mapping and sub-surface water-ice confirmation
  • Orbiter High Resolution Camera – for High-resolution topography mapping
  • Chandra’s Surface Thermo-physical Experiment – for Thermal conductivity and temperature gradient
  • Alpha Particle X-ray Spectrometer and Laser Induced Breakdown Spectroscopy – for In-situ elemental analysis and abundance in the vicinity of landing site

Glimpse of Chandrayaan- 1:

  • Chandrayaan-1 was India’s first mission to the moon, which was launched by Polar Satellite Launch Vehicle, PSLV-C11 on October 22, 2008, from Sriharikota.
  • Chandrayaan-1 made more than 3,400 orbits around the moon.
  • It was operational for 312 days till August 29, 2009. 
  • The lift-off mass of Chandrayaan-1 was 1380 kg, according to ISRO

Chandrayaan-1 key achievements: 

  • The Chandrayaan-1 discovered traces of water on the moon-a path-breaking discovery in the world of space science. 
  • Chandrayaan-1 also discovered water ice in the North polar region of the Moon.
  •  It also detected Magnesium, Aluminium and Silicon on the lunar surface. 
  • Global imaging of the moon is another achievement of this mission.

Scientific instruments on-board Chandrayaan-1: 

  • There were eleven scientific instruments onboard Chandrayaan-1 spacecraft.
  •  Five of them were Indian and other six were from ESA (3), NASA (2) and Bulgarian Academy of Sciences (1) selected through ISRO Announcement of Opportunity (AO). 
  • Two of the ESA instruments had Indian collaboration

Far side of the moon:

  • The far side of the Moon is the hemisphere of the Moon that always faces away from Earth. 
  • The far side’s terrain is rugged with a multitude of impact craters and relatively few flat lunar maria compared to the near side.
  • It has one of the largest craters in the Solar System, the South Pole–Aitken basin. 
  • Both sides of the Moon experience two weeks of sunlight followed by two weeks of night; even so, the far side is sometimes called the “dark side of the Moon”, where “dark” is used to mean unseen rather than lacking sunlight.
  • About 18 percent of the far side is occasionally visible from Earth due to libration.
  • The remaining 82 percent remained unobserved until 1959, when it was photographed by the Soviet Luna 3 space probe.
  • The Apollo 8 astronauts were the first humans to see the far side with the naked eye when they orbited the Moon in 1968. 
  • All manned and unmanned soft landings had taken place on the near side of the Moon, until 3 January 2019 when the Chang’e 4 spacecraft made the first landing on the far side. 
  • On 22 July ISRO launched Chandrayaan-2 lander and rover near the lunar south pole on the far side of the moon.

South Pole of the moon:

The lunar south pole is of special interest to scientists because of the occurrence of water ice in permanently shadowed areas around it. The lunar south pole region features craters that are unique in that the near-constant sunlight does not reach their interior.

Such craters are cold traps that contain a fossil record of hydrogen, water ice, and other volatiles dating from the early Solar System. In contrast, the lunar north pole region exhibits a much lower quantity of similarly sheltered craters

Important Lunar missions by other countries:

By the US-

  1. Surveyor 1 was NASA’s first lunar soft-lander in the uncrewed Surveyor program that was launched on May 30, 1966.
  2. Surveyor 3 launched on April 17, 1967 – It was the first Surveyor mission that carried a surface-soil sampling-scoop which was a huge deal.
  3. Apollo 11 was launched from Cape Kennedy on 16th July, 1969 and it was the first space flight that landed humans on the Moon. 
  4. Apollo 14 was launched on 31st January 1971 with 3 crew members on board. It was the first to land in the lunar highlands. It was marked as the last of the “H missions”, targeted landings with two-day stays on the Moon with two lunar moonwalks. 
  5. Apollo 15 was launched on 26th July 1971 which was the first “J mission” with a longer stay on the Moon and a greater focus on science as compared to the earlier landings. It also saw the first use of the Lunar Roving Vehicle.
  6. Apollo 17 was launched on 7th December 1972 which was the final mission of NASA’s Apollo program 

To date, the United States is the only country to have successfully conducted crewed missions to the Moon, with the last departing the lunar surface in December 1972

By the Soviet Union- 

  1. Luna 9 was an unmanned space mission of the Soviet Union’s Luna programme launched on 3rd February 1966. It became the first spacecraft to achieve a soft landing on the Moon.
  2. Luna 13 launched on 21st December 1966 landed in the region of Oceanus Procellarum (“Ocean of Storms”) of the Moon. 
  3. Luna 16, also known as Lunnik 16, was the first robotic probe to land on the Moon and return a sample of lunar soil to Earth. 
  4. Luna 17, also known as Lunik 17, was responsible for deploying the first robotic rover onto the surface of the Moon. 
  5. Luna 21 launched on 8th January 1973 with objectives of collecting images of the lunar surface, perform laser ranging experiments from Earth, observe solar X-rays and studying mechanical properties of the lunar surface material. 
  6. Luna 23 was launched on 28th October 1974 which intended to return lunar samples to Earth.

By China-

  1. Chang’e 3 is an unmanned lunar exploration mission operated by the China National Space Administration (CNSA) that was launched on December 2013.It incorporated a robotic lander and China’s first lunar rover. On 28 December 2015, Chang’e 3 discovered a new type of basaltic rock, rich in ilmenite, a black mineral.
  1. Chang’e 4 is a robotic spacecraft mission that was launched on 7th May 2018 as part of the second phase of the Chinese Lunar Exploration Program.It achieved the first soft landing on the far side of the Moon, on 3 January 2019