NAVIC

Why in News?

Officials at the Indian Space Research Organisation (ISRO) said here on Sa-turday that they were looking to launch at least three satellites before 2026 end to replenish the defunct satellites that are part of the “Indian GPS”, or the Navic (Navigation with Indian Constellation) system.

UPSC Relevance

Prelims, Mains – GS3, Achievements of Indians in Science & Technology; Indigenization of Technology and Developing New Technology.Awareness in the fields of IT, Space, Computers, Robotics, Nano-technology, Bio-technology and issues relating to Intellectual Property Rights.

PYQ

Q. With reference to the Indian Regional Navigation Satellite System (IRNSS), consider the following statements: (2018)

1. IRNSS has three satellites in geostationary and four satellites in geosynchronous orbits.
2. IRNSS covers entire India and about 5500 sq. Km beyond its borders.
3. India will have its own satellite navigation system with full global coverage by the middle of 2019.

Which of the statements given above is/are correct?

(a) 1 only

(b) 1 and 2 only

(c) 2 and 3 only

(d) None

Q. Why is Indian Regional Navigational Satellite System (IRNSS) needed? How does it help in navigation? (2018)

NaVIC System

• The Navigation with Indian Constellation (NaVIC) system, also known as the Indian Regional Navigation Satellite System (IRNSS), is India’s indigenous satellite navigation system.
• It is designed to provide accurate location services, primarily within a 1,500 km radius of India.
• The system has enhanced accuracy over the Indian subcontinent, due to its unique orbital design.
• NaVIC serves as a fallback system in case access to foreign constellations like the American GPS, Russian GLONASS, or Chinese BeiDou is denied during conflicts.

Importance – contribute to India’s self-reliance (“Atmanirbhar Bharat”)

National Security and Defense

• NavIC is a direct response to a past vulnerability. During the 1999 Kargil War, the U.S. denied India access to GPS data, highlighting the risk of relying on foreign-controlled systems. NavIC prevents this from happening again by providing a secure and uninterrupted supply of precise location and timing data. It’s a key part of the military’s strategic operations, including missile guidance, troop movements, and border surveillance. The system has a dedicated, encrypted service for authorized military users to ensure its resilience against jamming or spoofing.

Economic and Civilian Applications

• Logistics : The Indian government has mandated NavIC-enabled trackers on commercial vehicles, improving efficiency in logistics, transportation, and fleet management.
• Mobile Devices: The integration of NavIC into modern smartphones and other consumer devices is boosting the development of location-based services and apps, fostering domestic innovation in the tech sector.
• Disaster Management: NavIC provides vital, real-time location data for relief and rescue operations during natural disasters like floods and earthquakes. It also provides a dedicated safety-of-life alert dissemination service for fishermen.
• Agriculture and Surveying: Farmers can use NavIC for precision farming, while surveyors can use it for high-precision mapping and land-use planning.

Current Status of the NaVIC Constellation

• Operational Satellites: Nine satellites have been launched since 2013, but only eight reached their intended orbit.
• Defunct Satellites: Based on a Right to Information (RTI) request, five satellites are completely defunct, with all three of their onboard atomic clocks not working.
• Partial Functionality: In one of the three satellites with some functionality, two out of its three atomic clocks have failed.
• Fully Functional Satellites: Only two satellites in the entire constellation have fully functional atomic clocks.
• Recent Launches: ISRO launched NVS-01 in May 2023, which successfully reached its designated orbit. However, NVS-02, launched in January 2025, failed to reach the required orbit.

The Atomic Clock Problem

• Imported Clocks: The atomic clocks in the current constellation were imported from the firm SpectraTime.
• Critical Failure: A significant number of these imported clocks have failed, rendering five satellites completely defunct.
• High-Precision Requirement: These clocks are crucial for providing the accurate timing and location services that are the very purpose of the navigation system. Each satellite is equipped with five such clocks.

What is an Atomic Clock?

An atomic clock is a super-accurate timepiece that works by measuring the “ticking” of atoms. Think of a grandfather clock that uses a swinging pendulum to keep time. An atomic clock uses atoms as its “pendulum.”

Each type of atom vibrates at a specific, constant frequency when it is in the right energy state. The atomic clock counts these vibrations. For example, a second is defined as the time it takes for a cesium-133 atom to vibrate exactly 9,192,631,770 times.

Examples of Atomic Clocks

• Cesium Atomic Clocks: These are the most common type and are used to define the international standard for time, Coordinated Universal Time (UTC). The NIST-F2, a cesium fountain clock at the National Institute of Standards and Technology (NIST) in the U.S., is a primary time standard.
• Rubidium Atomic Clocks: These are simpler and more compact than cesium clocks. They are often used in commercial applications where a balance between accuracy and size is needed, such as in telecommunications.
• Hydrogen Maser Clocks: These clocks offer excellent short-term stability and are used in scientific research and for applications like radio astronomy.
• Optical Atomic Clocks: A newer generation of atomic clocks, optical clocks use atoms like strontium or ytterbium. They operate at much higher frequencies than traditional atomic clocks.

Global Navigation Satellite Systems

• GPS is the oldest and most widely used GNSS, developed and operated by the United States. It’s a key part of daily life for most people, powering navigation apps, fitness trackers, and in-car GPS units. It consists of over 30 satellites in medium Earth orbit (MEO) that transmit signals to receivers on Earth to determine a precise location.
• GLONASS is the GNSS of the Russian Federation. It was developed to provide an alternative to GPS and is widely used within Russia and other countries. The system has 24 satellites in MEO and is particularly effective for navigation in high-latitude regions due to its orbital design.
• Galileo is a GNSS created by the European Union. Unlike GPS and GLONASS, Galileo was designed specifically for civilian use. It aims to provide highly accurate and reliable positioning, navigation, and timing services to users worldwide. The system has 26 satellites in orbit, with a plan for a full constellation of 30.
• BeiDou is China’s GNSS. It started as a regional system but has since expanded to provide global coverage. It is now a key part of China’s technological and military strategy. The system includes satellites in various orbits, including geostationary and MEO, giving it a unique architecture.

Regional Navigation Systems

In addition to the global systems, several countries operate regional navigation satellite systems (RNSS) that provide coverage over a more limited geographic area.

• NaVIC (Navigation with Indian Constellation): Operated by India, this system provides coverage over India and a surrounding area of approximately 1,500 km.
• QZSS (Quasi-Zenith Satellite System): Operated by Japan, this system is primarily designed to augment GPS signals in the Asia-Oceania region, improving accuracy in urban and mountainous areas.