Perigee vs Apogee: The Definitive Differences & Decision Guide
Published by VsMatrix Editorial Team • Updated for 2026 Standards
Perigee is the point in the elliptical orbit of a satellite or the Moon where it is closest to Earth (approx. 363,300 km for the Moon), causing it to appear up to 14% larger and 30% brighter (a 'Supermoon') while traveling at its fastest orbital speed. Apogee is the orbital point where the celestial body is farthest from Earth (approx. 405,500 km for the Moon), where it appears smallest (a 'Micromoon') and moves at its slowest orbital velocity.
Apogee for Molniya satellite broadcast dwell times, apogee kick motor burns, and maximum orbital coverage
Perigee for spectacular Supermoons, extreme tidal ranges, and lowest satellite rocket communications latency
Side-by-Side Comparison Matrix
Direct technical specifications and distinguishing traits
| Key Criteria | Perigee | Apogee | Verdict |
|---|---|---|---|
| Distance from Earth (Lunar Orbit) | Closest approach: approximately 363,300 kilometers (225,623 miles) from Earth's center | Farthest distance: approximately 405,500 kilometers (251,966 miles) from Earth's center | Closest vs Farthest Point |
| Orbital Velocity (Kepler's 2nd Law) | Maximum velocity; the Moon travels fastest along its orbital trajectory (approx. 1.08 km/s) | Minimum velocity; the Moon travels slowest along its orbital trajectory (approx. 0.97 km/s) | Perigee Fastest Orbital Speed |
| Visual Size & Brightness (Full Moon) | Appears roughly 14% larger in angular diameter and up to 30% brighter in the night sky (Supermoon) | Appears roughly 14% smaller in diameter and 30% dimmer in the night sky (Micromoon) | Perigee Brighter & Larger Supermoon |
| Ocean Tidal Gravitational Influence | Stronger gravitational tidal pull; produces Perigean Spring Tides (King Tides) with high coastal water levels | Weaker gravitational tidal pull; produces subdued tidal ranges with lower high tides | Perigee Maximum Tidal Bulge |
| Spacecraft Satellite Operations | Lowest atmospheric orbital drag; ideal point to fire rocket engines for efficient burns (Oberth effect) | Maximum dwell time; Molniya communications satellites linger over high-latitude ground stations for hours | Application Dependent |
Interactive Decision Assistant: Which One Should You Choose?
Select your primary use case below to see which option fits your exact requirements:
- Planning astrophotography sessions to photograph full Supermoons rising over city skylines at maximum visual size
- Calculating Oberth effect propulsion maneuvers where firing rocket thrusters at maximum speed yields the highest energy efficiency
Can You Swap or Substitute Them?
Perigee and apogee apply specifically to orbits around Earth. If an object is orbiting the Sun, the corresponding terms are Perihelion and Aphelion; around Jupiter they are Perijove and定Apojove; for generic orbits around any body, they are Periapsis and Apoapsis.
Common Mistakes & Misconceptions
Thinking the Moon's distance to Earth stays constant. The Moon's orbit is an ellipse with an eccentricity of roughly 0.0549, causing its distance to vary by over 42,000 kilometers (26,000 miles) every single month.
Frequently Asked Questions
Concise answers to common queries regarding Perigee and Apogee
What is an anomalistic month?
An anomalistic month is the time it takes the Moon to travel from perigee to perigee, averaging approximately 27.55 days (slightly shorter than a synodic month from full moon to full moon).
What is a 'Supermoon'?
A Supermoon is a popular term for a perigee-syzygy: a Full Moon (or New Moon) that occurs within 90% of its closest approach to Earth, making it appear noticeably larger and brighter in the sky.
Why does a satellite move slowest at apogee?
Kepler's Second Law of Planetary Motion dictates that a line connecting a satellite to Earth sweeps out equal areas in equal times. As distance increases at apogee, the satellite must slow down to satisfy conservation of angular momentum.
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