Calculateur d'Excentricité Orbitale
Calculez l'excentricité d'une orbite elliptique.
km
km
Eccentricity
0.016711
Demi-grand axe149,600,000 km
Eccentricity vs Periapsis Distance
Formule
## Orbital Eccentricity Eccentricity describes how elongated an orbit is (0 = circle, approaching 1 = very elongated ellipse). ### Formula **e = (r_a - r_p) / (r_a + r_p)** Semi-major axis: **a = (r_a + r_p) / 2**
Exemple Résolu
Earth: perihelion 147.1M km, aphelion 152.1M km.
- 01e = (152.1M - 147.1M) / (152.1M + 147.1M)
- 02e = 5M / 299.2M ≈ 0.01672
- 03a = 299.2M / 2 = 149.6M km
Questions Fréquentes
What eccentricity is a circle?
A perfect circle has e = 0. Most planets have e < 0.1.
What does e = 1 mean?
Eccentricity of 1 is a parabolic escape trajectory. Above 1 is hyperbolic.
Which planet is most eccentric?
Mercury at about 0.2056 among the eight planets.