📘 Q.5 IAS Prelims 2023 — Science & Technology (Satellite Navigation Systems)
🧷 Authentic Classroom Explanation by IAS Monk
📌 The Question:
Which one of the following countries has its own Satellite Navigation System?
(a) Australia
(b) Canada
(c) Israel
(d) Japan
✅ Answer: (d) Japan
🧑🏫 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 — USA
- GLONASS — Russia
- Galileo — European Union
- BeiDou — 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:
• Australia ❌ — No independent satellite navigation system
• Canada ❌ — Relies on GPS
• Israel ❌ — No independent GNSS
• Japan ✅ — Operates QZSS, its own regional satellite navigation system
Hence, Japan is the correct answer.
🔍 Curiosity Raiser:
🛰️ Why does Japan need a special navigation system when GPS already exists?
📚 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
🧘 IAS Monk Whisper:
🌀 Navigation is not about knowing where you are — it is about knowing where you can go.
