NISAR's orbit regime is?

Question

NISAR's orbit regime is?

1. A. GTO
2. B. GEO
3. C. Polar sun-sync (Correct answer)
4. D. LEEO

Correct Answer

Option C — Polar sun-sync

Detailed Solution & Explanation

The correct answer is Polar sun-synchronous.

Key Points

• NISAR operates in a polar sun-synchronous orbit, the standard regime for Earth-observation satellites.
• A sun-synchronous orbit crosses any given latitude at the same local solar time on each pass, so lighting conditions stay consistent and images taken weeks apart can be compared directly.
• A polar path lets the satellite cover the entire globe as the Earth rotates beneath it — impossible from a geostationary position.

Additional Information

• NISAR — the NASA-ISRO Synthetic Aperture Radar mission — is a joint Earth-observation project carrying dual-frequency radar: an L-band instrument from NASA and an S-band instrument from ISRO.
• Being radar-based, it images through cloud and darkness, making it valuable for monitoring ecosystems, ice sheets, land deformation and natural hazards.
• Orbit types to keep distinct: LEO (roughly 160-2,000 km, used for Earth observation and the ISS), MEO (navigation constellations), GEO (35,786 km, communications and weather, appearing fixed over one point) and GTO (the transfer ellipse used to reach GEO).

प्रश्न (हिन्दी में)

NISAR की कक्षा व्यवस्था क्या है?

1. A. GTO
2. B. GEO
3. C. ध्रुवीय सूर्य-तुल्यकालिक
4. D. LEEO