HEO, also known as Molniya, stands for which orbit type?

• A. High Earth Orbit
• B. Geosynchronous Orbit
• C. Highly Elliptical Orbit
• D. Highly Eccentric Orbit

Answer: (C)

The question tests understanding that HEO means a path that is highly elongated in shape. A highly elliptical orbit has a long, stretched ellipse with a very far apogee and a closer perigee, which creates extended visibility over certain regions when the orbit is timed with the right tilt and period. Molniya is a classic example of this type: it uses a roughly 12-hour period, a high eccentricity, and an inclination around 63.4 degrees, with a low perigee and a very distant apogee. This configuration keeps the satellite over northern latitudes for a large portion of each orbit, making it ideal for coverage there. The other terms are less specific to Molniya’s famous setup: a generic high Earth orbit lacks the characteristic shape; a geosynchronous orbit implies a 24-hour period and usually a near-equatorial, circular path; while describing it as highly eccentric is technically close, the standard label in this context is Highly Elliptical Orbit.