UPSC (2026)Prelims MCQs based on the recent issue related to NavIC and the failure of the atomic clock onboard IRNSS-1F.

  UPSC (2026)Prelims MCQs based on the recent issue related to NavIC and the failure of the atomic clock onboard IRNSS-1F.

Q1.

With reference to NavIC, consider the following statements:

1. It is India’s indigenous satellite navigation system.

2. It provides navigation services globally similar to GPS.

3. It is developed and operated by the Indian Space Research Organisation.

Which of the statements given above are correct?

A. 1 only
B. 1 and 3 only
C. 2 and 3 only
D. 1, 2, and 3

Answer: B

Explanation:

• Statement 1 – Correct (NavIC is India’s own navigation system).

• Statement 2 – Incorrect (NavIC provides regional coverage only: India + ~1500 km).

• Statement 3 – Correct (Developed by ISRO).

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Q2.

Atomic clocks in navigation satellites are primarily used for:

A. Generating power for satellites
B. Maintaining communication with ground stations
C. Measuring precise signal travel time for positioning
D. Stabilizing satellite orbit

Answer: C

Explanation:
Navigation systems calculate location using the time taken for signals to travel from the satellite to the receiver. Even nanosecond-level errors can cause large positional errors, so atomic clocks ensure extremely accurate timing.

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Q3.

Each satellite in the NavIC constellation typically carries how many atomic clocks for redundancy?

A. 1
B. 2
C. 3
D. 5

Answer: C

Explanation:
Each NavIC satellite carries three atomic clocks so that if one fails, others can continue providing accurate timing.

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Q4.

The atomic clocks used in earlier NavIC satellites were procured from:

A. Japan
B. France
C. Switzerland
D. Israel

Answer: C

Explanation:
The clocks were imported from SpectraTime, a Switzerland-based company.

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Q5.

Which of the following correctly describes the coverage area of NavIC?

A. Entire world
B. Asia-Pacific region only
C. India and up to about 1500 km beyond its borders
D. Indian Ocean only

Answer: C

Explanation:
NavIC provides regional navigation services covering India and about 1500 km around it.

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Q6.

Which of the following countries operate global satellite navigation systems?

1. United States

2. China

3. European Union

4. India

Select the correct answer using the code below:

A. 1 and 2 only
B. 1, 2, and 3 only
C. 1, 3, and 4 only
D. 1, 2, 3, and 4

Answer: B

Explanation:

Global systems:

• Global Positioning System – USA

• BeiDou Navigation Satellite System – China

• Galileo – EU

India’s NavIC is regional, not global.

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Q7.

Which of the following best explains the strategic importance of NavIC for India?

A. It helps India control global navigation services.
B. It reduces dependence on foreign navigation systems during conflicts.
C. It replaces satellite communication systems.
D. It provides weather forecasting services.

Answer: B

Explanation:
NavIC acts as a strategic backup navigation system in case India loses access to foreign systems like GPS during geopolitical tensions.

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Q8.

Consider the following statements regarding the NVS series satellites:

1. They are meant to replace ageing NavIC satellites.

2. They use indigenously developed rubidium atomic clocks.

3. The first satellite in this series was launched in 2023.

Which of the statements given above are correct?

A. 1 and 2 only
B. 2 and 3 only
C. 1 and 3 only
D. 1, 2 and 3

Answer: D

Explanation:

• NVS-01 launched in 2023.

• They replace ageing satellites.

• They use indigenous rubidium atomic clocks.

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Q9.

Which of the following services rely heavily on satellite navigation systems such as NavIC?

1. Maritime navigation

2. Disaster management

3. Telecommunications timing

4. Missile guidance

Select the correct answer:

A. 1 and 2 only
B. 1, 2 and 3 only
C. 2, 3 and 4 only
D. 1, 2, 3 and 4

Answer: D

Explanation:
Satellite navigation systems support:

• Transport navigation

• Disaster response

• Telecommunications synchronization

• Defence and missile guidance

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Q10.

Which one of the following best describes Indian Standard Time synchronization through satellites?

A. It uses atomic clocks onboard navigation satellites.
B. It uses ground-based quartz clocks only.
C. It depends exclusively on GPS signals from the US.
D. It is derived from astronomical observations only.

Answer: A

Explanation:
Satellite navigation systems use atomic clocks to transmit precise timing signals, which can be used to synchronize Indian Standard Time across devices and networks.