UPSC PRELIMS 2020: Chandrayaan-2


Topic: Chandrayaan-2


Topic in Syllabus: Science and Technology



  • The furthest that any spacecraft has gone from the equator was Surveyor 7, launched by NASA, that made a moon landing way back on January 10, 1968. This spacecraft landed near 40-degree south latitude.
  • Its lander module, called Vikram, will land at a location very close to the south pole of the moon, near a latitude of about 70 degree south of lunar equator.
  • It is easier and safer to land near the equator.


Conditions at Equator of Moon:

  • The terrain and temperature are more hospitable, and conducive for longer and sustained operation of instruments.
  • The surface here is even and smooth, very steep slopes are almost absent, and there are fewer hills or craters.
  • Sunlight is present in abundance, at least on the side facing the earth, thus offering regular supply of energy to solar-powered instruments.


Conditions at Polar Regions:

  • The polar regions of the moon, however, are a very different, and difficult, terrain.
  • Many parts lie in a completely dark region where sunlight never reaches, and temperatures can go below 230 degree Celsius.
  • Lack of sunlight and extreme low temperatures create difficulty in operation of instruments.
  • There are large craters all over the place, ranging from a few cm in size to those extending to several thousands of kilometres.
  • As a result, the polar regions of the moon have remained unexplored.
  • There are indications of presence of ice molecules in substantial amounts in the deep craters in this region.
  • The extremely cold temperatures here mean that anything trapped here would remain frozen in time, without undergoing much change. The rocks and soil in this region could therefore provide clues to early solar system.

Therefore, there is an immense potential to reveal new science through the exploration of polar regions of the moon.

Chandrayaan-2 was to be launched by India and Russia in 2011; it’s delayed but better

  • Chandrayaan-2 was originally scheduled to be launched way back in 2011 itself, immediately after Chandrayaan-1 which was launched in 2008 and remained functional in its orbit till about a year later.
  • Chandrayaan-2 was supposed to be a joint collaborative mission between India and Russia.
  • While the Indian Space Research Organisation (ISRO) was to provide the rocket and the Orbiter module, the lander and rover modules were to come from Russia’s Roscosmos space agency.
  • ISRO did not have the capability to build its own lander and rover at that time.
  • The kind of lander and rover that Russia was preparing to send on Chandrayaan-2, however, developed problem on a different mission.
  • The new proposed design was found to be incompatible to Chandrayaan-2.
  • Russia had to eventually pull itself out from the collaboration, which left ISRO to make efforts to develop its own lander and rover through research and development.
  • This delay also provided ISRO additional time to improve on the design of the main spacecraft.

At 2.1 km above Moon surface, ISRO loses contact with Vikram

  • India’s hopes of becoming the first nation to touch down on the Moon’s South Polar region seems to have ended in disappointment as it lost contact with the Vikram lander of Chandrayaan-2, moments before the historic touchdown on Saturday.
  • Chandrayaan-1 had also sent a vehicle to the lunar South Pole, though that spacecraft crash landed into the ground, in November 2008, rather than land intact.
  • Sivan had earlier described Chandrayaan 2 as the “most complex mission ever undertaken by ISRO” and said that the prospect of the landers’ 15 minute descent — navigating its way autonomously — as “terrifying”.
  • Out Of the 38 previous attempts of ‘soft landing’ on the lunar surface so far, only 20 have been successful. Successful Orbiter
  • But all is not lost. More than half of the scientific instruments it carried to the Moon are safe on the orbiter, which continues to hover around 100 km above the Moon.
  • It will spend the next year mapping the lunar surface and studying the deposits of water ice at the South Pole.


Why presence of Water on Moon matters:

  • It has totally changed the way scientists now view the moon and has led to a renewed interest in lunar exploration.
  • Presence of water is crucial for the hopes of using moon as a future launch pad to send probes deeper in to space.
  • Human beings can use moon for extended period stays which is not possible in the absence of water.
  • A lot of water is believed to be present in the polar regions of the moon, trapped as ice in deep craters.
  • It can be used for life support and manufacturing rocket fuel.


Forms of Water on Moon:

  • Lunar surface is full of oxides of different elements. These oxides could react with hydrogen ion in the solar winds to make hydroxyl molecules, which could combine again with hydrogen to make H20.
  • The water could also have come from external sources.


Sample Question:

What are the objectives of launching Chandrayaan-2 moon mission?

a) To map the surface of the moon.
b) Signature of water-ice on the lunar surface.
c) To collect data on minerals and formation of rocks.
d) All the above

Answer: d)

Explanation: Scientific objectives are to map the Moon’s surface, its mineral and element content, moonquakes and signatures of water-ice on the lunar surface.