 INTRODUCTION

Exploring the Mysteries of the Moon: The Chandrayaan Missions

The Moon, Earth's closest celestial neighbor, has long fascinated humankind with its enigmatic beauty and its
profound influence on our planet's tides, cultures, and imagination. In the pursuit of unraveling the lunar mysteries and
expanding our knowledge of the lunar landscape, India embarked on a remarkable journey with its Chandrayaan
missions.
The word "Chandrayaan," derived from the Sanskrit words "chandra" (moon) and "yana" (craft), aptly encapsulates
the essence of these missions – they are lunar craft, designed to venture into the enigmatic realm of the Moon.
Through these missions, the Indian Space Research Organisation (ISRO) has made a significant mark in the field of
space exploration, joining the league of nations engaged in lunar exploration.
The Chandrayaan missions represent a series of ambitious lunar expeditions undertaken by India, each with its
unique objectives and scientific goals. These missions have not only advanced our understanding of the Moon but
have also brought India to the forefront of lunar research. They have ignited the imaginations of scientists and space
enthusiasts around the world and set the stage for future lunar exploration.
This article takes you on a journey through India's Chandrayaan missions, exploring their key highlights,
discoveries, and significance in the realm of lunar exploration. From Chandrayaan-1, the maiden mission that made
groundbreaking discoveries, to Chandrayaan-2, the ambitious venture that captured global attention, and beyond, we
will delve into the missions' objectives, challenges, and the exciting possibilities they hold for the future.
Join us as we embark on a celestial journey, where science, technology, and the thirst for knowledge come
together to reveal the lunar mysteries hidden within the vast expanse of the Moon. The Chandrayaan missions
exemplify India's unwavering commitment to pushing the boundaries of space exploration and advancing our
understanding of the cosmos.
  Chandrayaan-1: India's Lunar Triumph
In the annals of space exploration, India's Chandrayaan-1 mission stands as a remarkable testament to scientific
ambition, technological prowess, and international collaboration. Launched on October 22, 2008, by the Indian Space
Research Organisation (ISRO), Chandrayaan-1 was India's first lunar exploration mission. Over the course of its brief
but eventful journey, this spacecraft not only discovered water molecules on the Moon's surface but also played a
pivotal role in advancing our understanding of Earth's nearest celestial neighbor.

 Mission Objectives
The Chandrayaan-1 mission had several key objectives:
1. Mapping the Lunar Surface: One of the primary goals was to create a high-resolution, 3D map of the Moon's
surface. This mapping was crucial for future lunar missions and scientific research.
2. Studying Lunar Topography: The spacecraft aimed to analyze the Moon's mineral composition and terrain,
providing valuable insights into its geological history.
3. Detecting Water on the Moon: Chandrayaan-1 was equipped with instruments capable of detecting water molecules
on the lunar surface, shedding light on the Moon's past and potential resources.
4. Exploring the Moon's Poles: The mission sought to investigate the Moon's polar regions, where water ice deposits
were suspected to exist.

 The Journey to the Moon

Chandrayaan-1 embarked on its journey to the Moon aboard India's Polar Satellite Launch Vehicle (PSLV-C11). After
a successful launch, it entered lunar orbit on November 8, 2008. The spacecraft's initial phase involved a series of
orbit adjustments and checks to prepare for its scientific objectives.Once in orbit, Chandrayaan-1 began its meticulous
mapping of the Moon's surface using its Terrain Mapping Camera (TMC) and Hyperspectral Imager. These
instruments provided valuable data on lunar topography and mineral composition, contributing to our understanding
of the Moon's geological history.

 Discovering Water on the Moon

One of the most significant discoveries made by Chandrayaan-1 was the presence of water molecules on the lunar
surface. This discovery was made possible by the Moon Impact Probe (MIP), which was released from the spacecraft
and crash-landed near the Moon's south pole. The MIP's Moon Impact Spectrometer (MIS) detected traces of water
vapor, confirming the presence of water molecules on the Moon.This discovery had profound implications for future
lunar exploration and potential human colonization efforts. Water is essential for sustaining life and can be used to
generate oxygen and hydrogen for rocket fuel. The presence of lunar water raised hopes of establishing a sustainable
human presence on the Moon in the future.

 Chandrayaan-1's Unexpected End

Unfortunately, Chandrayaan-1's mission came to an unexpected end on August 29, 2009, when ISRO lost contact with
the spacecraft. The exact cause of this communication failure remains unclear, but it marked the conclusion of
Chandrayaan-1's operational phase. Despite its premature end, the mission had achieved many of its scientific
objectives. The spacecraft had completed over 3,400 orbits of the Moon and had transmitted a wealth of data back to
Earth, including detailed maps of the lunar surface and critical findings related to water on the Moon.

 Legacy and Impact

Chandrayaan-1's legacy extends far beyond its operational life. It demonstrated India's growing capabilities in space
exploration and paved the way for future ambitious missions. ISRO's successful launch and management of the
mission garnered international recognition and respect. The discovery of water on the Moon by Chandrayaan-1 ignited
interest from space agencies worldwide. Subsequent lunar missions, such as NASA's Lunar Reconnaissance Orbiter
and the Chinese Chang'e series, built upon the findings of Chandrayaan-1 and further explored the Moon's resources
and potential for human exploration.
Chandrayaan-1 also highlighted the importance of international collaboration in space exploration. India cooperated
with various nations, including the United States, in sharing data and expertise, fostering an environment of global
cooperation in lunar research.
  Chandrayaan-2: India's Ambitious Lunar Mission
In the annals of space exploration, India etched its name with the launch of Chandrayaan-2, a ground-breaking lunar
mission that captured the world's attention. This ambitious venture, initiated by the Indian Space Research
Organisation (ISRO), aimed to build on the success of its predecessor, Chandrayaan-1, and further India's reputation
as a spacefaring nation. With a vision to unravel the mysteries of the Moon, Chandrayaan-2 embarked on a journey
filled with challenges and triumphs.

 The Genesis of Chandrayaan-2

The inception of Chandrayaan-2 can be traced back to Chandrayaan-1, India's maiden lunar mission launched in 2008.
Chandrayaan-1 made significant discoveries, including the detection of water molecules on the Moon's surface. This
success served as a catalyst for the development of Chandrayaan-2, a more complex and ambitious
mission.Chandrayaan-2 was officially announced in 2007, and its primary objectives were to conduct a detailed study
of the Moon's topography, mineral composition, and exosphere. Additionally, it aimed to examine the presence of
water ice on the lunar south pole and explore the Moon's origin and evolution.

 The Structure of Chandrayaan-2

Chandrayaan-2 comprised three major components: the Orbiter, the Lander named Vikram, and the Rover named
Pragyan. Each component had specific tasks and responsibilities, working in tandem to achieve the mission's
objectives.
1. The Orbiter: The Orbiter was the spacecraft that would remain in orbit around the Moon. It was equipped with a
suite of scientific instruments designed to study the Moon's surface, measure the composition of the exosphere, and
capture high-resolution images.
2. The Lander (Vikram): Vikram was designed to make a soft landing near the lunar south pole. It carried the Pragyan
Rover, which was intended to explore the Moon's surface and conduct experiments. Vikram was equipped with a
variety of scientific instruments, including a seismometer and a thermal probe, to study the Moon's geology and
thermal properties.
3. The Rover (Pragyan): Pragyan was a six-wheeled robotic rover designed to explore the lunar surface, collect data,
and conduct experiments. It was equipped with instruments such as an alpha particle X-ray spectrometer and a laser-
induced breakdown spectroscope to analyze the Moon's composition.

 The Launch and the Journey

Chandrayaan-2 embarked on its journey to the Moon on July 22, 2019, with a successful launch atop India's most
powerful rocket, the GSLV Mark III. The launch marked a significant milestone for ISRO, demonstrating its capability
to undertake complex interplanetary missions. Following its launch, Chandrayaan-2 embarked on a series of Earth-
bound maneuvers and lunar orbit insertion maneuvers to gradually reach its intended orbit around the Moon. These
precise maneuvers showcased ISRO's expertise in celestial navigation.

 The Challenges Faced

However, not all stages of Chandrayaan-2's mission were smooth sailing. The most critical moment, the soft landing
of Vikram on the lunar surface, proved to be a nail-biting ordeal. As Vikram descended towards the Moon on
September 6, 2019, it encountered a deviation from its intended trajectory, and communication with the lander was
lost. The entire world watched anxiously as ISRO attempted to re-establish contact with Vikram. Unfortunately, the
attempt was unsuccessful, and Vikram was declared lost.

 The Orbiter's Triumph

While Vikram's loss was undoubtedly a setback, the Orbiter continued to circle the Moon and functioned exceptionally
well. In fact, it surpassed its expected mission life and continued to send valuable data and images back to Earth. The
Orbiter's longevity and success highlighted the resilience and adaptability of ISRO's technology.

 Scientific Discoveries and Contributions

Despite the challenges faced during the soft landing, Chandrayaan-2 made significant scientific contributions. The
data collected by the Orbiter, including detailed images of the lunar surface and the Moon's exosphere, provided
valuable insights into the Moon's geological history. Additionally, the detection of water ice in the polar regions had
profound implications for future lunar exploration and resource utilization.

Chandrayaan-2's Legacy
Chandrayaan-2 demonstrated India's prowess in space exploration and bolstered ISRO's reputation on the global stage.
While the soft landing did not go as planned, the mission's overall success in achieving its scientific objectives and the
endurance of the Orbiter were noteworthy achievements.Furthermore, Chandrayaan-2 paved the way for future lunar
missions, both by India and international collaborators. The mission's findings about the Moon's water ice and
geological features generated renewed interest in lunar exploration, setting the stage for potential future missions
focused on resource utilization and sustained lunar presence.
  Chandrayaan-3
Chandrayaan-3 has made history by becoming the first mission to soft-land on the lunar south pole, a region that
has never been explored before. The mission aimed to demonstrate safe and soft lunar landing, rover mobility, and in-
situ scientific experiments.

 India now joins the United States, Russia, and China as one of the few countries to successfully land on the
Moon.

 How did Chandrayaan-3 Prevail over Obstacles

Encountered in the Previous Mission?
 Chandrayaan-3's successful landing came after the setback of the Chandrayaan-2 mission's landing failure in
2019.
o The Vikram lander of Chandrayaan-2 had lost control and communication during descent, leading to a
crash on the lunar surface.
 Lessons from the Chandrayaan-2 mission were applied to Chandrayaan-3, focusing on a "failure-based"
design approach to anticipate and mitigate potential issues.
o Critical changes included strengthening the lander's legs, increasing fuel reserves, and enhancing
landing site flexibility.

 Why did Chandrayaan-3 Choose Moon's Near Side for

Landing?
 Chandrayaan-3 aimed to investigate "permanently shadowed regions" near the South Pole for potential
water-ice and resources.
o The Vikram lander's controlled descent achieved one of the closest approaches to the Moon's South
Pole.
 While a notable achievement, Vikram's landing occurred on the Moon's near side, unlike China's Chang'e
4 on the far side.
o The near side, visible from Earth due to synchronous rotation, covers 60% of the Moon.
o The far side, though not always in darkness, remained hidden until the Soviet spacecraft Luna 3
captured images in 1959.
 Astronauts aboard the Apollo 8 mission in 1968 became the first humans to observe the far side
directly.
 The near side boasts smoother surfaces and numerous 'maria' (large volcanic plains), while the far side
features massive craters from asteroid impacts.
o The lunar crust on the near side is thinner, causing volcanic lava to flow and fill craters over time, creating
flat terrains.
 The decision to land on the near side was driven by the mission's primary goal of a controlled soft landing.
o Landing on the far side would require a relay for communication due to the lack of direct line-of-sight
with Earth.
  What are the Intended Actions for Chandrayaan-3 after
its Landing?
 Chandrayaan-3 is expected to operate for at least one lunar day (14 Earth days) on the lunar surface.
o The Pragyan rover will move around the landing site within a radius of 500 meters, conducting
experiments and sending data and images to the lander.
o The Vikram lander will relay the data and images to the orbiter, which will then transmit them to
Earth.
 Lander and Rover modules are collectively equipped with advanced scientific payloads.
o These instruments are designed to conduct comprehensive investigations into diverse facets of lunar
characteristics, encompassing terrain analysis, mineralogical composition, surface chemistry,
atmospheric attributes, and crucially, the exploration for water and potential resource reservoirs.
o The propulsion module that carried the lander and rover configuration till 100 km lunar orbit also
has a Spectro-polarimetry of Habitable Planet Earth (SHAPE) payload to study the spectral and Polari
metric measurements of Earth from the lunar orbit.
  What are ISRO's Future Expeditions?
 Chandrayaan-4: Navigating the Path of Lunar Evolution
o Building upon past missions, Chandrayaan-4 emerges as a potential candidate for a sample return
mission.
 If successful, it could mark the next logical step after Chandrayaan-2 and 3, offering the capability
to retrieve lunar surface samples.
o The mission holds promise for advancing our understanding of the Moon's composition and history.

 LUPEX: Lunar Polar Exploration (LUPEX) mission, a collaborative effort between ISRO and JAXA
(Japan), is poised to explore the Moon's Polar Regions.
o It will be specifically designed to venture into permanently shaded areas.
o Investigating the presence of water and assessing the potential for a sustainable long-term station are
among LUPEX's objectives.

 XPoSat (X-ray Polari meter Satellite): It is India’s first dedicated polarimetry mission to
study various dynamics of bright astronomical X-ray sources in extreme conditions.
o The spacecraft will carry two scientific payloads in a low earth orbit.

 NISAR: NASA-ISRO SAR (NISAR) is a Low Earth Orbit (LEO) observatory being jointly developed by
NASA and ISRO.
o NISAR will map the entire globe in 12 days and provide spatially and temporally consistent data for
understanding changes in Earth’s ecosystems, ice mass, vegetation biomass, sea level rise, ground
water and natural hazards including earthquakes, tsunamis, volcanoes and landslides.

 Gaganyaan: Gaganyaan mission aims to send humans to space and return them safely to
Earth. The mission will consist of two unmanned flights and one manned flight, using the GSLV Mk III
launch vehicle and a human-rated orbital module.
o The manned flight will carry three astronauts, including a woman, for up to seven days in low Earth
orbit.

 Shukrayaan 1: It is a planned mission to send an orbiter to Venus, the second planet from the Sun. It is
expected to study Venus’s geological and volcanic activity, emissions on the ground, wind speed, cloud cover,
and other planetary characteristics.

 Conclusion:
The Chandrayaan program reflects India's growing presence in space exploration and its dedication to advancing our
understanding of the Moon. Despite challenges, each mission has contributed valuable data and insights that benefit
lunar science. As India continues to reach for the stars, we can expect more exciting discoveries and lunar missions in
the years to come.
  Refferences
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surface/article67263267.ece#:~:text=This%20monumental%20achievement%20firmly
%20cemented,'%2030%2D40%20cm%20away.
2. https://www.drishtiias.com/daily-updates/daily-news-analysis/chandrayaan-3-successfully-lands-on-moon-s-
south-pole
3. https://www.isro.gov.in/Chandrayaan_1.html#:~:text=Chandrayaan%2D1%2C%20India's%20first
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4. https://en.wikipedia.org/wiki/Chandrayaan-1
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