Orbital Characteristics of Mars

Orbital Characteristics

Perihelion: 206,669,000 km, 1.381497 AE
Aphelion: 249,209,300 km, 1.665861 AE
Semi-major axis: 227,939,100 km, 1.523679 AE
Eccentricity: 0.093315
Orbital period: 686.971 days, 1.8808 days, 668.5991 sols
Synodic period: 779.96 days, 2.135 years
Average orbital speed: 24.077 km/s
Mean anomaly:
Inclination: 1.850°
Longitude of ascending node: 49.562°
Argument of perihelion: 286.537°

Satellites/moons: 2 (Phobos, Deimos)

Physical Characteristics of Mars

Physical Characteristics

Equatorial radius: 3,396.2 ± 0.1 km km (0.533 x Earth)
Flattening: 0.00589 ± 0.00015
Surface area: 144,798,500 km2 (0.284 x Earth)
Volume: 1.6318×1011 km3 (0.151 x Earth)
Mass: 6.4185×1023 kg (0.107 x Earth)
Mean density: 3.934 g/cm3
Equatorial surface gravity: 3.69 m/s2
Escape velocity: 5.027 km/s
Sidereal rotation period: 1.025957 day Earth days, 24.62296 h Earth hours
Axial tilt : 25.19°
Albedo: 0.15
Average surface temperatures: 186/268 K, -87/-5 °C, -125/23 °F
Apparent magnitude: +1.8 to −2.91
Angular diameter: 3.5—25.1"
The Atmosphere of Mars

The Atmosphere

  • 95.72% Carbon Dioxide (CO2)
  • 2.7% Nitrogen (N2)
  • 1.6% Argon
  • 0.2% Oxygen (O2)
  • 0.07% Carbon Monoxide (CO)
  • 0.03% Water vapor (H2O)
  • 0.01% Nitrogen Oxide (NO)
  • 2.5 ppm Neon
  • 300 ppb Krypton
  • 130 ppb Formaldehyde (H2CO)
  • 80 ppb Xenon
  • 30 ppb Ozone (O3)
  • 10 ppb Methane (CH4)

    Mars images:

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