Chandrayaan-1: India's First Mission to the Moon
A
complete study guide for students and UPSC aspirants
1. Introduction: Why Chandrayaan-1 Matters
On 22 October 2008, India launched its
first mission beyond Earth's orbit. Chandrayaan-1
was India's first lunar probe and the beginning of India's deep-space journey.
It was followed by Chandrayaan-2 (2019), Chandrayaan-3 (2023), the Mars Orbiter
Mission (2013) and Aditya-L1 (2023).
The name comes from Sanskrit: Chandra (Moon) + Yaan (vehicle or craft), so "Moon-craft".
For a UPSC aspirant, Chandrayaan-1 matters
for four reasons:
1.
Scientific: it contributed to the
discovery of water molecules on the Moon.
2.
Technological: it was India's first
mission to leave Earth's orbit and to deploy a probe that struck the Moon.
3.
Strategic: it made India the sixth
country to send a mission to the Moon, after the USSR, USA, Japan, the European
Space Agency (ESA) and China.
4.
Diplomatic: it carried instruments from
several countries and agencies, a model of "space diplomacy".
2. Background and Timeline of Approval
•
15 August 2003: Prime Minister Atal Bihari Vajpayee announced India's
lunar mission in his Independence Day speech. The project was sanctioned in
2003.
•
2003-2008: Design, payload selection,
building and testing. ISRO invited international scientists to propose
instruments, and several were selected.
•
22 October 2008: Launch.
•
29 August 2009: Radio contact with the
spacecraft was lost, and the mission was declared over.
Key
people
|
Role |
Name |
|
ISRO Chairman at launch |
G.
Madhavan Nair |
|
Project Director |
M.
Annadurai (later Director of ISRO Satellite
Centre, ISAC) |
Where
it was run from
•
The satellite was built at ISRO Satellite Centre (ISAC), Bengaluru.
•
It was launched from the Satish Dhawan Space Centre (SHAR),
Sriharikota, Andhra Pradesh.
•
The Spacecraft Control Centre was at ISTRAC (ISRO Telemetry, Tracking
and Command Network), Bengaluru.
•
Signals were received by the Indian Deep Space Network (IDSN) at Byalalu, near Bengaluru, which has
large dish antennas (18 m and 32 m).
•
Data was archived at the Indian Space Science Data Centre (ISSDC),
Byalalu.
3. Objectives of the Mission
Chandrayaan-1 had scientific, technological
and educational goals.
Scientific objectives
Technological objectives
Educational objective
•
Prepare a three-dimensional atlas of both the near side and far side of the
Moon.
•
Do chemical mapping of the entire lunar surface for elements such as
magnesium, aluminium, silicon, calcium, iron and titanium, as well as
radioactive elements like uranium and thorium.
•
Do mineralogical mapping to understand how the Moon formed and
evolved.
•
Search for water or ice, especially at the poles.
•
Study the lunar environment (radiation and particles).
•
Test the PSLV for launching a lunar mission.
•
Master the skills of deep-space navigation and
communication.
•
Release a Moon Impact Probe (MIP) to hit the lunar surface.
•
Test spacecraft systems in the
thermal and radiation environment of the Moon.
•
Inspire students and young
scientists, and create a trained workforce in space science.
4. The Launch Vehicle: PSLV-C11
Chandrayaan-1 was launched on PSLV-C11, the XL (extra-large) variant of the Polar Satellite Launch Vehicle.
•
The XL version uses six larger
strap-on boosters, giving it more lifting capacity than the standard PSLV.
•
PSLV-C11 was the first PSLV-XL launch, and it was used
to push the spacecraft toward a high elliptical orbit around Earth.
•
The spacecraft was placed in a Geosynchronous Transfer Orbit-like (highly
elliptical) orbit of about 255 km ×
22,860 km.
The PSLV is a four-stage rocket that
alternates solid and liquid propulsion (solid, liquid, solid, liquid). Its
reliability earned it the nickname "workhorse of ISRO".
5. The Spacecraft: Design and Features
•
Shape and size: roughly a cube of about
1.5 m on each side.
•
Mass: about 1,380 kg at launch, and about 675
kg after reaching lunar orbit (after burning most of the propellant).
•
Power: a single solar panel generating about 700
W at peak, with a lithium-ion
battery storing energy for periods when the Sun is blocked (eclipses).
•
Propulsion: a bipropellant system using a Liquid
Apogee Motor (LAM) of about 440 N for raising and lowering the orbit, plus
small thrusters for control.
•
Attitude control: three-axis stabilised, using star sensors, gyroscopes and reaction
wheels.
•
Communication: X-band for sending large payload data to Earth, and S-band for telemetry, tracking and
command.
•
Payloads: 11 scientific instruments, 5 Indian and 6 foreign.
6. The Eleven Payloads (Very Important for Prelims)
A. Indian payloads (5)
1.
Terrain Mapping Camera (TMC): a stereo
camera taking black-and-white (panchromatic) images with about 5 m resolution. It prepared a 3D map of
the Moon. Developed by the Space
Applications Centre (SAC), Ahmedabad.
2.
Hyper Spectral Imager (HySI): images the
Moon in many narrow wavelength bands (about 64 bands, visible and near-infrared) to map minerals. Also
developed by SAC.
3.
Lunar Laser Ranging Instrument (LLRI):
fires laser pulses at the surface and times their return to measure the height of lunar terrain precisely.
4.
High Energy X-ray Spectrometer (HEX):
detects high-energy X-rays and gamma rays (about 30-270 keV) to study
radioactive elements such as uranium and
thorium and to search for polar volatiles. Developed by the Physical Research Laboratory (PRL),
Ahmedabad, with ISRO.
5.
Moon Impact Probe (MIP): a 35 kg probe that separated from the
orbiter and crashed into the Moon (details in Section 8).
B. Foreign payloads (6)
From
ESA (European Space Agency), three instruments:
6.
Chandrayaan-1 Imaging X-ray Spectrometer (C1XS): maps major elements (magnesium,
aluminium, silicon, calcium, iron, titanium) by studying X-rays emitted
when solar radiation strikes the lunar surface. It was built by the UK's
Rutherford Appleton Laboratory with ISRO.
7.
Smart Near-Infrared Spectrometer (SIR-2):
studies the minerals of the Moon in near-infrared light. Built by the Max Planck Institute, Germany.
8.
Sub-keV Atom Reflecting Analyser (SARA):
studies how the solar wind interacts
with the lunar surface. It was a collaboration between Sweden, Switzerland,
Japan and India (ISRO's VSSC).
From
Bulgaria:
9.
Radiation Dose Monitor (RADOM-7):
measured the radiation environment in space around Earth and the Moon, which is
important for future human missions.
From
NASA (USA), two instruments:
10.
Mini-SAR (Miniature Synthetic Aperture Radar): searched for water-ice
in permanently shadowed craters near the poles.
11.
Moon Mineralogy Mapper (M3): an imaging
spectrometer built by Brown University
and NASA's JPL. It mapped minerals and found signs of water.
Memory
trick: "3
ESA, 2 NASA, 1 Bulgaria" = 6 foreign; "TMC, HySI, LLRI, HEX, MIP" = 5 Indian.
7. The Journey: From Earth to the Moon
Reaching the Moon was a step-by-step
process.
Stage 1: Launch and Earth orbit raising
Stage 2: Lunar Transfer Trajectory
Stage 3: Lunar Orbit Insertion (LOI)
Stage 4: Reducing the orbit
Stage 5: Operations
After PSLV-C11 placed the satellite in an
elliptical orbit of about 255 × 22,860 km, ISRO fired the on-board engine five times between about 23 October and
3 November 2008. Each firing at the point nearest to Earth (perigee) raised the
farthest point (apogee). Eventually the apogee reached about 380,000 km, close to the Moon's
distance.
In early November 2008 the spacecraft was
put on a path toward the Moon.
On 8
November 2008, the engine fired to slow the spacecraft so that the Moon's
gravity could capture it. This is a delicate manoeuvre: too little braking and
the spacecraft flies past the Moon, too much and it may crash. It succeeded,
and Chandrayaan-1 entered an elongated lunar orbit.
Over the next days, the orbit was lowered
step by step. By 12 November 2008,
the spacecraft was in a nearly 100 km
circular polar orbit, passing over both lunar poles. This orbit lets the
Moon rotate underneath, so over time the spacecraft can scan the entire
surface.
After the Moon Impact Probe was released
and the instruments were switched on, the orbiter began its mapping and
scientific work.
8. The Moon Impact Probe (MIP)
The MIP is one of the most frequently asked facts.
•
Date: 14 November 2008.
•
Mass: 35 kg.
•
It separated from the orbiter
and descended to the lunar surface,
landing near the Shackleton Crater
at the south pole.
•
It carried three instruments:
o
a video imaging system (for pictures during descent),
o
a radar altimeter (to measure altitude),
o
a mass spectrometer called CHACE
(Chandra's Altitudinal Composition Explorer) to study the thin lunar
atmosphere (exosphere).
•
The Indian tricolour was painted on the probe. ISRO described India as
becoming the fourth country to place its flag on the Moon.
•
The impact site was later named
Jawahar Point, honouring Jawaharlal Nehru; 14 November is his
birth anniversary.
•
CHACE detected water in the thin lunar
atmosphere during the descent.
The MIP was a stepping stone for later soft-landing capability (Chandrayaan-2
and 3). The MIP was a hard-landing
(crash) probe, not a soft lander.
9. Major Scientific Discoveries
9.1 Water molecules on the lunar surface (M3)
9.2 Water-ice at the poles (Mini-SAR)
9.3 Water in the exosphere (CHACE)
9.4 Mapping the chemistry (C1XS)
9.5 Mineral discoveries
9.6 Solar wind interaction (SARA)
9.7 3D maps and images (TMC)
9.8 Radiation (RADOM-7)
In September
2009, NASA scientists announced that M3 had detected signs of water (H₂O) and hydroxyl (OH) on the
lunar surface, spread widely and especially stronger at higher latitudes. This
overturned the older idea that the Moon was completely dry.
•
The water is very thin: it exists as molecules
attached to the soil grains, not as lakes or oceans.
•
A likely source is the solar wind. Hydrogen ions (protons)
from the Sun strike the surface, and combine with oxygen in the minerals.
•
M3 found the signal through a
characteristic absorption at wavelengths around 2.8-3.0 micrometres.
In March
2010, NASA announced that Mini-SAR had found over 40 small craters near the north pole containing ice. The total
estimate was at least about 600 million
metric tonnes of water-ice. These craters are permanently shadowed and extremely cold, so ice can survive for
billions of years.
The MIP's mass spectrometer detected water
vapour in the thin atmosphere during descent.
C1XS detected magnesium, aluminium and silicon on the surface, and supported the
theory of the Moon's early magma ocean.
Chandrayaan-1 data showed pure anorthosite-rich rock (a
light-coloured, calcium-aluminium-rich rock) in some regions, supporting the Lunar Magma Ocean hypothesis: early in
its history the Moon was largely molten, and lighter minerals floated up to
form the crust.
SARA found that a surprisingly large fraction (roughly 20%) of the solar
wind protons are reflected from the Moon's surface as neutral hydrogen
atoms, rather than absorbed. It also helped reveal "mini-magnetospheres" around regions with localised
magnetic fields.
The camera produced high-resolution stereo
images for 3D terrain maps and for studying craters, mountains and landing
sites.
It measured radiation doses, useful for
planning future crewed missions.
10. The Problems the Mission Faced
Chandrayaan-1 was planned for two years, but it worked for about 312 days (a little under 10.5 months).
•
Heating: The spacecraft ran hotter than
expected, because of intense sunlight and radiation reflected from the lunar
surface.
•
Orbit raised: In May 2009, ISRO raised the orbit from 100 km to about 200 km to help control temperature.
•
Star sensor failure: The star sensors,
used for orientation, failed, and ISRO shifted to using backup methods.
•
Loss of contact: On 29 August 2009, radio contact was lost, and the mission was
officially declared over.
ISRO said that about 95% of the mission's objectives had been achieved. The spacecraft
completed roughly 3,400 orbits and
sent back a very large amount of data (tens of thousands of images).
The "rediscovery"
In 2016,
NASA used ground-based radar to
locate Chandrayaan-1 still circling the Moon, roughly 200 km above the surface.
This was a remarkable demonstration of how a lunar spacecraft can be tracked
after it has been silent for years.
11. Cost and Economics
The mission cost about ₹386 crore (roughly US$80 million at the time), which was low
compared with similar missions from other countries. This supports the idea of
ISRO's "frugal innovation",
which is a useful example for Mains answers.
12. Quick-Revision Fact Table (For Prelims)
|
Item |
Detail |
|
Launch date |
22 October 2008 |
|
Launch site |
Satish Dhawan Space Centre, Sriharikota |
|
Launch vehicle |
PSLV-C11 (XL version) |
|
Announced by |
PM Atal Bihari Vajpayee (15 Aug 2003) |
|
ISRO Chairman |
G. Madhavan Nair |
|
Project Director |
M. Annadurai |
|
Launch mass |
About 1,380 kg |
|
Orbit |
100 km polar (later 200 km) |
|
Lunar Orbit Insertion |
8 November 2008 |
|
MIP impact |
14 November 2008, near Shackleton crater |
|
Payloads |
11 (5 Indian + 6 foreign) |
|
Planned life |
2 years |
|
Actual operation |
About 312 days |
|
Contact lost |
29 August 2009 |
|
Cost |
About ₹386 crore |
|
Main discovery |
Water/hydroxyl on the Moon, ice at the
poles |
|
Rank |
India: 6th nation to send a lunar mission |
13. Chandrayaan-1 in the Bigger Picture
Link to later missions
• Chandrayaan-2 (22 July 2019): launched
on GSLV Mk-III with an orbiter, lander (Vikram) and rover (Pragyan). The lander
crashed during descent in September 2019, but the orbiter continues to function and sends valuable data.
• Chandrayaan-3 (14 July 2023): launched
on LVM3. On 23 August 2023, Vikram made a successful soft landing
near the lunar south polar region,
making India the fourth country to
soft-land on the Moon and the first
to land near the south pole. The landing site was named "Shiv Shakti Point", and 23 August is celebrated as National Space Day.
•
Future plans: Chandrayaan-4 (a
sample-return mission) and a joint India-Japan mission, LUPEX, have been discussed or approved. Check the latest status
before your exam.
Other Indian space milestones
Policy context
•
Mangalyaan / Mars Orbiter Mission (2013-14): India's first Mars mission, which entered Mars orbit in its first
attempt.
•
Aditya-L1 (2023): India's first solar
observatory mission.
•
Gaganyaan: India's human spaceflight
programme.
•
IN-SPACe (2020) was created to open the
space sector to private companies.
•
NSIL (NewSpace India Limited) is the
commercial arm of ISRO.
•
Indian Space Policy 2023 defines roles
for ISRO, IN-SPACe and private firms.
•
India signed the Artemis Accords in 2023.
14. Why Chandrayaan-1 Matters: Multi-Dimensional Analysis
(For Mains)
Science and Technology (GS-3)
International Relations and Diplomacy (GS-2)
Economy and Development (GS-3)
Security and Strategy
Ethics and Society
•
Gave India deep-space mission
experience (navigation, communications, thermal control).
•
Contributed to global lunar
science, notably the discovery of water.
•
Built scientific capacity in
instrument design.
•
Demonstrated international scientific cooperation
with ESA, NASA and Bulgaria.
•
Raised India's prestige and
soft power.
•
Shows how space cooperation
builds trust.
•
Showed cost-effective engineering.
•
Spin-offs include better
satellite technology, remote sensing and communication.
•
Encouraged the space industry
and technical education.
•
Space capabilities are dual-use: the same rocket and
navigation skills have civilian and defence applications.
•
It strengthened India's
standing in the new "space race" for lunar resources.
•
The cost-benefit debate:
critics ask why a developing country spends on space; supporters point to
long-term returns in technology, agriculture, disaster management and
communication.
15. Possible Mains Questions
1.
"Chandrayaan-1 laid the foundation for India's later lunar and
planetary missions." Discuss.
2.
Examine the scientific significance of the discovery of water on the
Moon and its implications for future exploration.
3.
How does India's space programme reflect the idea of frugal
innovation and international cooperation?
4.
Discuss the role of space diplomacy with reference to missions with
international payloads.
A quick answer structure
•
Introduction: one or two lines with core
facts (launch, aim).
•
Body: scientific contributions,
technological learning, strategic and diplomatic value, and limitations.
•
Way forward / Conclusion: link to
Chandrayaan-2 and 3, the private space sector and future human missions.
16. Practice Questions (Prelims-Style)
Q1.
Chandrayaan-1 was launched using which launch vehicle? (a) GSLV Mk-II (b) PSLV-XL (c) LVM3 (d) SLV-3 Answer: (b)
Q2.
The Moon Impact Probe of Chandrayaan-1 was targeted near which crater? (a) Tycho (b) Shackleton (c) Copernicus (d) Aristarchus Answer: (b)
Q3.
Which instrument on Chandrayaan-1 searched for ice in polar craters? (a) HySI (b) LLRI (c) Mini-SAR (d) RADOM-7 Answer: (c)
Q4.
Which of the following were among the foreign payloads on Chandrayaan-1?
1.
SARA 2. C1XS 3. HEX 4. M3
Select the correct answer: (a) 1, 2 and 4 only (b) 1 and 3 only (c) 2 and 3
only (d) 1, 2, 3 and 4 Answer: (a).
HEX was an Indian payload.
Q5.
Which of the following statements about Chandrayaan-1 is/are correct?
1.
It was launched in 2008.
2.
It was India's first mission to
the Moon.
3.
It carried 11 payloads. Select
the correct answer: (a) 1 only (b) 1 and 2 only (c) 2 and 3 only (d) 1, 2 and 3
Answer: (d)
17. Common Mistakes to Avoid
•
Mixing up missions: Chandrayaan-1 was an
orbiter plus impact probe. It had no
lander or rover. Chandrayaan-2 had an orbiter, lander and rover. Chandrayaan-3
had a lander and rover plus a propulsion module.
•
Confusing "hard landing" with "soft landing": The MIP crashed on purpose, so it was a hard landing.
•
Confusing who discovered what: Water in
the surface soil came from NASA's M3.
The polar ice estimate came from Mini-SAR.
Water in the exosphere came from CHACE
on India's MIP.
•
Mixing the launch vehicle: Chandrayaan-1
used the PSLV (XL), while Chandrayaan-2 and 3 used the heavier GSLV Mk-III /
LVM3.
•
Forgetting the Indian-versus-foreign split: 5 Indian and 6 foreign payloads.
18. One-Page Summary (Last-Minute Revision)
Chandrayaan-1 was India's first lunar mission, launched on 22 October 2008 by PSLV-C11 from Sriharikota. It carried 11 payloads (5 Indian and 6 from ESA, Bulgaria and NASA) and entered a 100 km polar orbit around the Moon on 12 November 2008. The Moon Impact Probe struck near Shackleton crater on 14 November 2008. The mission helped confirm water and hydroxyl on the Moon (M3), found polar ice (Mini-SAR), and mapped the Moon's chemistry and minerals. Overheating and the failure of key systems ended contact on 29 August 2009, after about 312 days, but ISRO reported about 95% of objectives met. The mission cost about ₹386 crore, showed ISRO's frugal innovation and led to Chandrayaan-2 and Chandrayaan-3.