๐ Q.5 IAS Prelims 2023 โ Science & Technology (Satellite Navigation Systems)
๐งท Authentic Classroom Explanation by IAS Monk
๐ The Question:
Which one of the following countries has its own Satellite Navigation System?
(a) Australia
(b) Canada
(c) Israel
(d) Japan
โ Answer: (d) Japan
๐งโ๐ซ Classroom Explanation:
Satellite Navigation Systems provide real-time positioning, navigation, and timing (PNT) services by using signals from satellites.
Currently, the major Global Navigation Satellite Systems (GNSS) are:
- GPS โ USA
- GLONASS โ Russia
- Galileo โ European Union
- BeiDou โ China
Apart from these, some countries operate regional navigation systems:
- India operates NavIC (IRNSS)
- Japan operates QZSS (Quasi-Zenith Satellite System)
Now check the options:
โข Australia โ โ No independent satellite navigation system
โข Canada โ โ Relies on GPS
โข Israel โ โ No independent GNSS
โข Japan โ
โ Operates QZSS, its own regional satellite navigation system
Hence, Japan is the correct answer.
๐ Curiosity Raiser:
๐ฐ๏ธ Why does Japan need a special navigation system when GPS already exists?
๐ Enrichment Notes (UPSC Edge):
- QZSS complements GPS by improving accuracy in urban canyons and mountainous regions
- Satellites follow highly inclined elliptical orbits, staying nearly overhead over Japan
- Used in:
- Disaster management
- Autonomous vehicles
- Precision agriculture
- Maritime navigation
- NavIC (India) covers India and ~1500 km beyond its borders
๐ง IAS Monk Whisper:
๐ Navigation is not about knowing where you are โ it is about knowing where you can go.















