Why GEO launches favor the equatorial plane Geosynchronous satellites are placed in the Earth’s equatorial plane primarily because only this plane yields what key property?

Introduction / Context:
A satellite is geosynchronous if its orbital period equals Earth’s rotation. It is geostationary only if the orbit is both geosynchronous and equatorial with zero eccentricity, making the satellite appear fixed in the sky.

Given Data / Assumptions:

• Target: continuous coverage of a fixed Earth footprint.
• Orbit altitude: ~35,786 km (geosynchronous radius).
• Eccentricity ≈ 0 and inclination ≈ 0 for truly “stationary.”

Concept / Approach:
The equatorial plane with zero inclination ensures no north–south apparent motion. Zero eccentricity ensures no east–west oscillation in longitude. Together these conditions produce a geostationary satellite fixed above one longitude, ideal for broadcast and point-to-point services requiring stationary ground antennas.

Step-by-Step Solution:
Recognize distinction: geosynchronous (period match) vs geostationary (period + equatorial + circular).Only equatorial, circular orbits provide a “stationary” sub-satellite point.Therefore the unique property provided by the equatorial plane is stationarity.

Verification / Alternative check:
Inclined geosynchronous orbits produce figure-eight ground tracks (analemmas), requiring tracking antennas—not stationary.

Why Other Options Are Wrong:

• 24-hour period occurs for any inclination if the semi-major axis is correct.
• Global communication is not possible with a single GEO; multiple satellites are needed.
• Zero-gravity environment is unrelated; microgravity exists in all orbits.

Common Pitfalls:

• Using “geosynchronous” and “geostationary” interchangeably.
• Ignoring the role of eccentricity in apparent satellite drift.

Final Answer:
A stationary (geostationary) satellite relative to Earth’s surface