What is Highly Elliptical Orbit (HEO)?

What is Highly Elliptical Orbit (HEO)?

• A. Orbit providing long coverage over low latitudes.
• B. Satellite orbit well above Earth’s atmosphere with fixed ground track.
• C. Orbit optimized for near-polar, rapid cycling.
• D. Orbit providing long coverage over high latitudes.

Answer: (D)

Highly Elliptical Orbit means the satellite follows a very elongated path around Earth, so it spends most of its time far from the planet and moves slowly at the farthest point (apogee). That slow motion at apogee translates into long dwell times over the region beneath that part of the orbit. When the apogee is oriented toward high latitudes, the satellite lingers over those polar and high‑latitude areas for many hours, providing extended coverage there. This is the hallmark of HEO: extended visibility over high latitudes, unlike orbits that keep a fixed ground track, circle the Earth quickly, or favor low-latitude coverage. An example class of HEOs, like Molniya-type orbits, uses a high inclination to maximize this long-duration coverage of northern regions.

Highly Elliptical Orbit means the satellite follows a very elongated path around Earth, so it spends most of its time far from the planet and moves slowly at the farthest point (apogee). That slow motion at apogee translates into long dwell times over the region beneath that part of the orbit. When the apogee is oriented toward high latitudes, the satellite lingers over those polar and high‑latitude areas for many hours, providing extended coverage there. This is the hallmark of HEO: extended visibility over high latitudes, unlike orbits that keep a fixed ground track, circle the Earth quickly, or favor low-latitude coverage. An example class of HEOs, like Molniya-type orbits, uses a high inclination to maximize this long-duration coverage of northern regions.