Info

mars

Mars
Designations
Pronunciation UK English: /mɑːz/
US English: /ˈmɑːrz/
Adjectives Martian
Orbital characteristics [2]
Epoch J2000
Aphelion 1.6660 AU
249.2 Gm
Perihelion 1.3814 AU
206.7 Gm
Semi-major axis
1.523679 AU
227.9392 Gm
Eccentricity 0.0934
Orbital period
1.8808 Julian years
686.971 d
668.5991 sols
Synodic period
779.96 days
2.135 Julian years
Average orbital speed
24.077 km/s
Mean anomaly
19.373°
Inclination 1.850° to ecliptic
5.65° to Sun's equator
1.67° to invariable plane[1]
Longitude of ascending node
49.558°
Argument of perihelion
286.502°
Satellites 2
Physical characteristics
Mean radius
3,389.5±0.2 km[a][3]
Equatorial radius

3,396.2±0.1 km[a][3]

0.533 Earths
Polar radius

3,376.2±0.1 km[a][3]

0.531 Earths
Flattening 0.00589±0.00015
Surface area

144,798,500 km2

0.284 Earths
Volume

1.6318×1011 km3[4]

0.151 Earths
Mass

6.4171×1023 kg[5]

0.107 Earths
Mean density
3.9335±0.0004 g/cm³[4]
Surface gravity

3.711 m/s²[4]

0.376 g
Moment of inertia factor
0.3662±0.0017[6]
Escape velocity
5.027 km/s
Sidereal rotation period

1.025957 d

24h 37m 22s[4]
Equatorial rotation velocity
868.22 km/h (241.17 m/s)
Axial tilt
25.19° to its orbital plane[7]
North pole right ascension

21h 10m 44s

317.68143°
North pole declination
52.88650°
Albedo 0.170 (geometric)[8]
0.25 (Bond)[7]
Surface temp.minmeanmax
Kelvin 130 K 210 K[7] 308 K
Celsius −143 °C[10] −63 °C 35 °C[11]
Fahrenheit −226 °F[10] −82 °F 95 °F[11]
Apparent magnitude
+1.6 to −3.0[9]
Angular diameter
3.5–25.1″[7]
Atmosphere[7][12]
Surface pressure
0.636 (0.4–0.87) kPa
0.00628 atm
Composition by volume
  • 95.97% carbon dioxide
  • 1.93% argon
  • 1.89% nitrogen
  • 0.146% oxygen
  • 0.0557% carbon monoxide