ISRO INSAT-3C Mission: Objectives, Launch Date, Status, UPSC Notes

India’s space programme, led by the Indian Space Research Organisation (ISRO), has evolved from modest beginnings into one of the most respected space agencies in the world. Over the years, ISRO has designed and executed a range of missions—from satellite navigation, Earth observation, interplanetary exploration, to solar studies—that have not only enhanced India’s technological self-reliance but also contributed to global scientific collaboration. Its cost-effective approaches and mission diversity—from Chandrayaan and Mangalyaan to Aditya-L1 and the upcoming Gaganyaan—have become case studies in innovation.

For UPSC aspirants, ISROs journey is more than current affairs—it directly intersects with the syllabus of General Studies Paper 3 (Science & Technology), provides examples for GS Paper 2 (International Relations, Governance), and can enrich perspectives in the Essay Paper, Ethics, and even Optional subjects like Geography or PSIR. In this article, we will explore detailed insights about ISRO INSAT-3C Mission —its objectives, timelines, key technologies, and strategic implications.

ISRO INSAT-3C Mission Overview

INSAT-3C was designed and executed with the primary aim of supporting advancements in Communication, Broadcasting.ISRO positioned INSAT-3C in Geostationary Orbit to meet its operational goals.

• For this mission, INSAT-3C was placed into orbit using Ariane-42L.
• The spacecraft was sent into orbit from Kourou, French Guyana.
• INSAT-3C aimed to accomplish the primary task of Augment INSAT capacity for telecom, TV, VSAT services.
• INSAT-3C was further expected to aid in Mobile Satellite Services (MSS).
• The mission is currently in the stage of Successful, Mission completed.

INSAT-3C Space Mission Overview for UPSC
Mission Name	INSAT-3C
Mission Abbreviation	N/A
Mission Type	Communication, Broadcasting
Target Celestial Body or Orbit	Geostationary Orbit
Primary Objective	Augment INSAT capacity for telecom, TV, VSAT services
Secondary Objectives	Mobile Satellite Services (MSS)
Mission Status	Successful, Mission completed

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Timeline & Milestones of ISRO INSAT-3C Mission

• The mission timeline of INSAT-3C began with its launch on 24/01/2002.
• The primary mission life of INSAT-3C is projected to conclude around Around 2014 (12 years planned life).

Timeline & Milestones
Proposal Date	N/A
Critical Design Review (CDR) Date	N/A
Assembly Complete Date	N/A
Launch Date	24/01/2002
Landing / Flyby Date	N/A
End of Primary Mission Date	Around 2014 (12 years planned life)

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ISRO INSAT-3C Mission Technical Specifications

The satellite’s technical blueprint included Mass 2750 kg; Power 275 kW, allowing for stability and performance in space.The choice of Geostationary, 74° E longitude aligned with the mission’s overall strategy for scientific observation and technical validation.

• For this Communication, Broadcasting effort, the scientific payloads onboard included Transponders (C, Ext-C, S-band), MSS transponder, ensuring compatibility with its planned orbit.
• INSAT-3C relied on C-band, Extended C-band, S-band to transmit navigation and system data to ground stations.

Technical Specifications
Spacecraft Technical Specifications	Mass 2750 kg; Power 275 kW
Scientific Payloads	Transponders (C, Ext-C, S-band), MSS transponder
Orbit Details	Geostationary, 74° E longitude
Communication Frequencies / Band	C-band, Extended C-band, S-band
Key Technologies Used	Indigenous communication satellite technology

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INSAT-3C Launch Information

• INSAT-3C was successfully launched on 24/01/2002 by ISRO.
• To execute the launch of INSAT-3C, the Ariane-42L was deployed.
• The mission was initiated from Kourou, French Guyana.

Launch Information
Launch Vehicle	Ariane-42L
Launch Site	Kourou, French Guyana

Who are the Stakeholders & Collaborators?

According to official information, ISRO were associated with the mission.

• Collaboration with Launch by Arianespace added a global dimension to the objectives of INSAT-3C.

Stakeholders & Collaboration
Agencies Involved	ISRO
Commercial Partners	N/A
International Partners	Launch by Arianespace
Payload Contributions by Partners	N/A
Data Sharing Policy	N/A

Outputs, Applications & Impact of ISRO INSAT-3C Mission

INSAT-3C, launched from Kourou, French Guyana, accomplished Continued expansion of INSAT services.INSAT-3C generated data outputs including Communication and broadcasting services.

• INSAT-3C considered aspects of sustainability through Standard satellite decommissioning procedures.
• The technologies developed under Communication, Broadcasting are relevant for Communication, broadcasting, VSAT.
• The mission was conceptualized in line with broader policy directions, including Augmenting INSAT capacity.
• Following the milestones achieved under INSAT-3C, ISRO has outlined potential developments such as INSAT/GSAT series to build a more robust mission series.

Outputs, Applications & Impact of INSAT-3C Mission
Data Outputs and Applications	Communication and broadcasting services
Major Achievements	Continued expansion of INSAT services
Applications in Civilian Life	Communication, broadcasting, VSAT
Impact on Policy & Global Collaboration	N/A
Environmental Impact & Sustainability	Standard satellite decommissioning procedures
Strategic Significance & Policy Alignment	Augmenting INSAT capacity
Follow-up Missions or Extensions	INSAT/GSAT series
Cost Estimate	N/A

ISRO INSAT-3C Space Mission Risks, Failures & Mitigation

Risks, Failures & Mitigation
Challenges Faced	N/A
Risk Mitigation Measures	N/A
Failures or Anomalies	N/A
Corrective Actions Taken	N/A
Lessons Learned	N/A

UPSC Relevance of ISRO INSAT-3C Space Mission

• Candidates should be able to identify which ISRO mission belongs to which application area, such as communication, meteorology, navigation, or planetary exploration.
• Incorporating current ISRO developments into GS answers can elevate them from generic to analytical, showing depth in understanding and real-world application.
• Case studies on transparent communication during mission failures or ISROs non-militaristic space stance fit well into discussions on ethical decision-making.
• ISRO’s satellite missions are highly relevant to Geography optional, especially under topics like remote sensing, resource mapping, and environmental monitoring.

Past UPSC Mains PYQs on ISRO Space Missions

Q1. Discuss the role of the private sector in the growth of the space industry in India. How has the governments policy of 2023 affected it? (2023, GS Paper 3 - Science & Technology)

Q2. What is India’s plan to have its own space station and how will it benefit our space programme? (2022 & 2019, GS Paper 3 - Science & Technology)

Q3. Space has been the next big frontier for mankind after sea and land. In this context, discuss Indias policy and preparedness for space wars. (2019, GS Paper 3 - Science & Technology)

Q4. Discuss the utility of the Mars Orbiter Mission (MOM) for India. (2016, GS Paper 3 - Science & Technology)

Q5. What do you understand by Standard Positioning Systems and Precision Positioning Systems in the GPS era? Discuss the advantages India perceives from its ambitious IRNSS programme employing just seven satellites. (2015, GS Paper 3 - Science & Technology)

Past UPSC Prelims PYQs on ISRO Space Missions

Q1 [2025]: GPS-Aided Geo Augmented Navigation (GAGAN) uses a system of ground stations to provide necessary augmentation. Which of the following statements is/are correct in respect of GAGAN?

I. It is designed to provide additional accuracy and integrity.
II. It will allow more uniform and high quality air traffic management.
III. It will provide benefits only in aviation but not in other modes of transportation.

Select the correct answer using the code given below.

(a) I, II and III
(b) II and III only
(c) I only
(d) I and II only

Correct Answer: (d) I and II only

Explanation: Statements I and II correctly describe the core purpose and benefit of the GAGAN system. (I) GAGAN is designed to augment GPS signals by correcting for errors, which provides much greater accuracy and guarantees the integrity (reliability) of the positioning information. (II) This enhanced accuracy and reliability directly enables more precise aircraft routing and landing procedures, thus improving the uniformity and quality of air traffic management.

Q2 [2022]: If a major solar storm (solar flare) reaches the Earth, which of the following are the possible effects on the Earth?

1. GPS and navigation systems could fail.
2. Tsunamis could occur at equatorial regions.
3. Power grids could be damaged.
4. Intense auroras could occur over much of the Earth.
5. Forest fires could take place over much of the planet.
6. Orbits of the satellites could be disturbed.
7. Shortwave radio communication of the aircraft flying over polar regions could be interrupted.

Select the correct answer using the code given below:

(a) 1, 2, 4 and 5 only
(b) 2, 3, 5, 6 and 7 only
(c) 1, 3, 4, 6 and 7 only
(d) 1, 2, 3, 4, 5, 6 and 7

Answer: The correct answer is (c).

Explanation: A major solar storm can disrupt GPS, power grids, satellite orbits, polar radio communication, and cause auroras, but cannot trigger tsunamis or forest fires.

Q3 [2020]: The experiment will employ a trio of spacecraft flying in formation in the shape of an equilateral triangle that has sides one million kilometres long, with lasers shining between the craft.” The experiment in question refers to

(a) Voyager-2
(b) New horizons
(c) Lisa Pathfinder
(d) Evolved LISA

Answer: The correct answer is (d) Evolved LISA.

Explanation: Evolved LISA (Laser Interferometer Space Antenna) is a planned space-based gravitational wave observatory by ESA and NASA, using three spacecraft in a triangular formation with laser beams to detect cosmic gravitational waves.

Q4 [2016]: Consider the following statements:

The Mangalyaan launched by ISRO

1. is also called the Mars Orbiter Mission
2. made India the second country to have a spacecraft orbit the Mars after USA
3. made India the only country to be successful in making its spacecraft orbit the Mars in its very first attempt

Which of the statement(s) given above is/are correct?

(a) 1 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1, 2 and 3

Answer: c) 1 and 3 only

Explanation: Mangalyaan is the informal name of Mars Orbiter Mission (MOM), launched by ISRO on 5 November 2013 and India is the only nation to date to have succeeded on its maiden attempt.

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UPSC Practice Questions on ISRO Space Missions

Q1. Satellites TeLEOS-2 and Lumelite-4 were launched in April 23 from Sriharikota by the launcher
1. SSLV-D2
2. LVM3-M4
3. PSLV-C55
4. GSLV-F12
Answer: Option 3
Solution: Satellites TeLEOS-2 and Lumelite-4 were launched on April 23, 2023, from Sriharikota by the launcher PSLV-C55. The PSLV-C55 is a mission conducted by the Indian Space Research Organisation (ISRO) using the Polar Satellite Launch Vehicle (PSLV).

Key Features of PSLV-C55:
- Launch Date: The PSLV-C55 mission was launched on April 22, 2023.
- Primary Payload: The mission carried two Singaporean satellites:
- TeLEOS-2: A synthetic aperture radar (SAR) satellite, developed to provide all-weather, day-and-night coverage of Singapore and the surrounding region. It is capable of high-resolution imaging.
- LUMELITE-4: A technology demonstration satellite designed for ship identification and tracking.
- Launch Vehicle: The PSLV-C55 used the PSLV Core Alone configuration, which is the lightest version of ISRO's workhorse launch vehicle. PSLV is known for its versatility and reliability, capable of launching various types of satellites into different orbits.
- Mission Highlights: The PSLV-C55 mission also incorporated ISRO's PSLV Orbital Experimental Module (POEM), which utilized the spent fourth stage of the PSLV as a platform for conducting in-orbit experiments. POEM-2 carried payloads from multiple organizations to conduct space research experiments, further optimizing the mission's utility.
- Launch Site: The mission was launched from Satish Dhawan Space Centre (SDSC), Sriharikota, India.

Q2. India's Mars rover will help in getting information about which planet?
1. Mars
2. Mercury
3. Jupiter
4. Venus
Answer: Mars
Solution: ISRO launched its Mars Orbiter Mission on 5th November 2013. It was the maiden interplanetary mission of ISRO. The mission got inserted into Martian orbit on 24th September 2014 in its first attempt. The mission completed its 1000 Earth days in its orbit on 19th June 2017. The mission was launched with an objective to explore and observe Mars surface features, morphology, mineralogy, and the Martian atmosphere. Mars Orbiter Mission was launched with an XL variant of the PSLV, PSLV C-25. Mars Orbiter Mission made ISRO the fourth space agency to achieve this feat after Roscosmos, NASA, and the European Space Agency. India is the first Asian country to reach Martian orbit as well as the first nation in the world to achieve this in its maiden attempt. The Mars Orbiter Mission (MOM) is also called Mangalyaan.

Q3. When will PSLV-C56 carrying DS-SAR satellite be launched from Singapore?
1. October 23
2. September 23
3. July 23
4. August 23
Answer: July 23
Solution: The PSLV-C56 mission is scheduled to launch in July 2023. The primary satellite on this mission is the DS-SAR satellite from Singapore. PSLV-C56 is part of the Polar Satellite Launch Vehicle (PSLV) series, operated by the Indian Space Research Organisation (ISRO). This mission aims to strengthen the cooperation between India and Singapore in the field of space technology and satellite applications.

Additional Information:
- PSLV (Polar Satellite Launch Vehicle) is an expendable launch vehicle developed and operated by ISRO. It is known for its reliability and versatility in launching satellites into different orbits, including geostationary transfer orbits, low Earth orbits, and sun-synchronous orbits. PSLV has been a workhorse for ISRO, with numerous successful missions since its first launch in 1993. It is capable of carrying multiple satellites in a single mission, making it a preferred choice for international satellite launches.

Q4. Which team of Indian Space Research Organisation (ISRO) won the Vigyan Team award in 2024?
1. Chandrayaan-2 Team
2. XPoSat Team
3. Aditya-L1 Team
4. Chandrayaan-3 Team
Answer: Chandrayaan-3 Team
Solution: The Chandrayaan-3 Team of ISRO was awarded the Vigyan Team award in 2024. Chandrayaan-3 is the third lunar exploration mission by the Indian Space Research Organisation (ISRO). The mission aims to demonstrate the capability of soft-landing on the lunar surface and operate a rover. Chandrayaan-3 was built upon the experience gained from the Chandrayaan-2 mission.

Additional Information:
- Chandrayaan-2 was launched on 22 July 2019. It aimed to explore the south pole of the Moon. The mission included an orbiter, a lander named Vikram, and a rover named Pragyan.
- Aditya-L1 is ISRO's mission to study the Sun. The mission aims to understand the dynamic processes of the Sun and its impact on the space environment.
- XPoSat (X-ray Polarimeter Satellite) is a dedicated mission to study cosmic X-ray sources. It aims to observe the polarization of X-rays from various sources like pulsars and black hole binaries.
- ISRO has successfully launched missions like Mars Orbiter Mission (Mangalyaan) and various communication satellites. It has made significant contributions to space exploration and satellite technology.

Q5. Which is India’s first dedicated Space Astronomy Observatory?
1. XPoSat
2. AstroSat
3. Aditya-L1
4. Chandrayaan-2
Answer: AstroSat
Solution: AstroSat is India's first dedicated multi-wavelength space telescope. AstroSat is India's first multi-wavelength space observatory, which aims to study the universe in multiple wavelengths such as visible, ultraviolet, and X-rays. It is designed to observe celestial sources in different wavelengths of light to help scientists understand the universe's various phenomena better.

Important Points:
- Ultraviolet Imaging Telescope (UVIT)
- Large Area Soft X-ray Spectrometer (LAXPC)
- Cadmium Zinc Telluride Imager (CZTI) for X-rays
- Visible Emission Line Coronagraph (VELC) for observing the Sun's corona

These instruments allow for a detailed study of different cosmic events like black holes, neutron stars, supernovae, and distant galaxies.

Additional Information:
- XPoSat (X-ray Polarimeter Satellite) is an upcoming mission by ISRO and is designed to study the polarization of cosmic X-rays. It is not India's first space astronomy observatory.
- Aditya-L1 is India's mission to study the Sun, focusing on understanding solar phenomena and their effect on space weather. It is not a general-purpose space astronomy observatory.
- Chandrayaan-2 is a mission aimed at exploring the Moon. It includes an orbiter, lander, and rover, but it is not designed as a space astronomy observatory.

Q6. Consider the following statements regarding ISRO's Kulasekarapattinam spaceport:
Statement 1: It is located in Nellore district of Andhra Pradesh.
Statement 2: This spaceport will focus on critical advancements in spacecraft and launch vehicle thermal management.
Statement 3: It is India's 2nd spaceport after Satish Dhawan Space Center.
Which of the above statements is/are correct?
1. 1 and 2
2. 1 and 3
3. 2 and 3
4. 1, 2 and 3
Answer: Statement 2 and Statement 3
Solution: Statement 1 is incorrect because the Kulasekarapattinam spaceport is located in Thoothukudi district of Tamil Nadu, not Nellore district of Andhra Pradesh. This spaceport will serve as ISRO's second launch complex, and its strategic location in Tamil Nadu is expected to enhance India's satellite launch capabilities. Statement 2 is correct as the Kulasekarapattinam spaceport will focus on advancements in spacecraft and launch vehicle thermal management. This is a key area for India's space mission goals. Thermal management is essential for ensuring the safety and longevity of spacecraft and satellites, as they face extreme temperatures during launch and in space. The spaceport will play a crucial role in research related to heat transfer, cooling systems, and fluid dynamics, which are critical for the next generation of spacecraft and satellite technologies. Statement 3 is correct because Kulasekarapattinam is indeed India's second spaceport. The first spaceport is the Satish Dhawan Space Center in Sriharikota, Andhra Pradesh. With the establishment of the Kulasekarapattinam spaceport, ISRO aims to strengthen its satellite launch capabilities, particularly for small satellite and polar launches. This new spaceport will also support ISRO's plans to expand its global satellite launch services.

In News: ISRO's Kulasekarapattinam spaceport in Tamil Nadu will see its first SSLV launch in 2027, marking a significant milestone for ISRO's expanding space infrastructure.

Key Points:
- Location: The Kulasekarapattinam spaceport is located in Thoothukudi, Tamil Nadu, and will serve as a major center for small satellite launches. Its strategic location enhances ISRO's capabilities for various types of space missions, particularly polar satellite launches.
- Thermal Management Focus: The spaceport will support ISRO's research in spacecraft and launch vehicle thermal management, a critical area for ensuring the safe operation and longevity of space missions. The spaceport's research will focus on innovations in heat transfer, cooling systems, and fluid dynamics.
- ISRO's 2nd Spaceport: Kulasekarapattinam is ISRO's second spaceport after the Satish Dhawan Space Center in Sriharikota. This new spaceport will help ISRO handle increased satellite launches and enhance its global presence in the satellite launch industry.

Q7. For the study of the Sun, ISRO developed the spacecraft:
1. Aditya L1
2. Vikram
3. Aditya
4. None of these
Answer: Aditya-L1
Solution: Aditya-L1 is ISRO's first solar mission. The aim is to study the outer layers of the Sun, including the corona, chromosphere, solar flares, solar wind, and magnetic field. The spacecraft was successfully launched on September 2, 2023, from Sriharikota, Andhra Pradesh. The spacecraft will reach Lagrange Point 1 (L1), a point where the gravitational forces of the Earth and the Sun balance, allowing for continuous observation of the Sun.

Instruments on Aditya-L1:
- VELC – Visible Emission Line Coronagraph
- SUIT – Solar Ultraviolet Imaging Telescope
- ASPEX, PAPA – Plasma Analyzers
- SoLEXS, HEL1OS, Magnetometer – Various solar observation instruments.

Q8. In February 2023, ISRO carried out the first successful launch using its new rocket.
1. Small Satellite Launch Vehicle
2. Geo Synchronous Satellite Launch Vehicle
3. Polar Satellite Launch Vehicle
4. Scramjet Engine-TD
Answer: Small Satellite Launch Vehicle
Solution: The Small Satellite Launch Vehicle (SSLV) is a new generation rocket developed by the Indian Space Research Organisation (ISRO) to meet the rising demand for small satellite launches. SSLV is designed as a cost-effective and flexible solution, capable of launching payloads up to 500 kg to Low Earth Orbit (LEO). The SSLV is a three-stage rocket that uses solid propulsion systems in all stages, making it simpler and faster to manufacture and assemble compared to other ISRO rockets. On February 10, 2023, ISRO successfully launched the SSLV-D2 mission, marking the first operational flight of the SSLV, which carried three payloads into orbit.

Additional Information:
- Comparison with Other ISRO Rockets:
- Polar Satellite Launch Vehicle (PSLV): Known as ISRO's workhorse, PSLV is capable of launching payloads up to 1,750 kg to Sun-Synchronous Orbit (SSO) and has been used for a wide range of missions, including Chandrayaan-1 and Mars Orbiter Mission.
- Geo Synchronous Satellite Launch Vehicle (GSLV): Designed for launching heavier payloads into Geostationary Transfer Orbit (GTO), GSLV is used for missions requiring higher altitudes, such as communication satellites.
- Scramjet Engine-TD: This is a technology demonstrator for air-breathing engines and is not a launch vehicle. It represents ISRO's efforts in developing advanced propulsion systems for future space missions.

Q9. What is the name of India's first privately developed rocket?
1. Bazoomq
2. Prarambh
3. Vikram-S
4. Skyroot
Answer: Vikram-S
Solution: Vikram-S is India’s first privately developed rocket, designed and built by the Hyderabad-based startup Skyroot Aerospace. It was successfully launched on November 18, 2022, from the Indian Space Research Organisation facility at Sriharikota. The mission, named Prarambh (The Beginning), marked a historic milestone for India's private space sector. Vikram-S is a single-stage, sub-orbital rocket powered by solid fuel and advanced composite materials, and it reached a peak altitude of 89.5 km. The rocket is part of the Vikram series, named after Dr. Vikram Sarabhai, the father of the Indian space program.

Additional Information:
- Skyroot Aerospace:
- A Hyderabad-based space technology startup founded in 2018 by former ISRO scientists.
- It aims to democratize access to space by developing cost-effective and flexible launch vehicles for small satellites.
- Skyroot’s rockets are designed with 3D-printed engines and advanced carbon composite structures.
- Prarambh Mission:
- The maiden mission of Skyroot Aerospace, symbolizing the beginning of private sector participation in India's space exploration.
- The payload included three customer satellites to validate the rocket’s performance.
- Vikram Series Rockets:
- A family of rockets under development by Skyroot Aerospace, designed for low-cost and on-demand satellite launches.
- The series comprises Vikram-I, Vikram-II, and Vikram-III, with varying payload capacities.
- Private Space Sector in India:
- The Indian government opened the space sector to private players in 2020, promoting innovation and investment.
- The establishment of IN-SPACe (Indian National Space Promotion and Authorization Center) facilitates private sector participation in space activities.
- Startups like Skyroot, Agnikul, and Pixxel are leading India’s private space revolution.

Q10. Consider the following space missions:
I. Axiom-4
II. SpaDeX
III. Gaganyaan
How many of the space missions given above encourage and support micro-gravity research?
1. Only one
2. Only two
3. All the three
4. None
Answer: All the three
Solution:
I. Axiom-4: Axiom Mission 4 (Ax-4) is a private space mission organized by Axiom Space, launched to the International Space Station (ISS). The ISS is a microgravity laboratory where astronauts conduct a variety of experiments in medicine, physics, biology, and materials science. Therefore, Axiom-4 enables microgravity research.

II. SpaDeX (Space Docking Experiment): SpaDeX is an Indian space mission by ISRO designed to demonstrate autonomous docking technology between satellites. The mission is expected to include studies and hardware testing in microgravity conditions since autonomous docking must function in orbit under such conditions. As such, SpaDeX contributes to microgravity-related R&D and technology validation.

III. Gaganyaan: Gaganyaan is India’s first crewed space mission being developed by ISRO. It aims to send humans into low Earth orbit (LEO), where microgravity conditions prevail. The crewed module will be used to conduct microgravity experiments related to biological sciences, physical sciences, and space medicine.

Thus, all three missions encourage and support microgravity research.

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