Satellite launch geometry — to directly attain a geostationary (synchronous) equatorial orbit, the preferred launch site latitude is:

Introduction / Context:
Geostationary (synchronous) orbits are circular, equatorial, and prograde with zero inclination relative to Earth’s equator. Achieving such an orbit most efficiently requires launching into an equatorial plane to avoid costly plane-change maneuvers at high velocity.

Given Data / Assumptions:

• Target orbit is geostationary: inclination i = 0°, period = sidereal day.
• Plane-change maneuvers in orbit are expensive in delta-v, especially at GEO speeds (~3.07 km/s).
• Earth rotation provides an eastward velocity boost greatest at the equator.

Concept / Approach:

Launching from the equator aligns the initial orbital plane with the Earth’s equator, eliminating inclination. Any non-equatorial site injects into an inclined orbit requiring a plane change later, increasing fuel requirements. Additionally, equatorial sites maximize the rotational speed assist, improving payload to orbit.

Step-by-Step Solution:

Verification / Alternative check (if short method exists):

Compute plane-change delta-v: Δv_pc ≈ 2vsin(i/2); at GEO speeds even a few degrees imply substantial propellant. i = 0° makes Δv_pc = 0.

Why Other Options Are Wrong:

Latitudes 30°, 45°, 60°, or poles inject into inclined planes that need correction. Polar launches are most inefficient for GEO plane matching.

Common Pitfalls (misconceptions, mistakes):

Assuming any latitude is equivalent because plane changes can be done “later”; underestimating the large Δv penalty of inclination changes at high orbital velocities.

Final Answer:

on the equator