Mars
...Roman god, see Mars (disambiguation).
Mars Astronomical symbol of Mars The planet Mars
Mars as seen by the Hubble Space Telescope
Orbital characteristics[1]
Epoch J2000
Aphelion 249,209,300 km
1.665861 AU
Perihelion 206,669,000 km
1.381497 AU
Semi-major axis 227,939,100 km
1.523679 AU
Eccentricity 0.093315
Orbital period 686.971 day
1.8808 Julian years
668.5991 sols
Synodic period 779.96 day
2.135 Julian years
Average orbital speed 24.077 km/s
Inclination 1.850°
5.65° to Sun's Equator
Longitude of ascending node 49.562°
Argument of perihelion 286.537°
Satellites 2
Physical characteristics
Equatorial radius 3,396.2 ± 0.1 km[2][3]
0.533 Earths
Polar radius 3,376.2 ± 0.1 km[2][3]
0.531 Earths
Flattening 0.00589 ± 0.00015
Surface area 144,798,500 km²
0.284 Earths
Volume 1.6318×1011 km³
0.151 Earths
Mass 6.4185×1023 kg
0.107 Earths
Mean density 3.934 g/cm³
Equatorial surface gravity 3.69 m/s²
0.376 g
Escape velocity 5.027 km/s
Sidereal rotation
period 1.025957 day
24.62296 h
Equatorial rotation velocity 868.22 km/h
Axial tilt 25.19°
North pole right ascension 21 h 10 min 44 s
317.68143°
North pole declination 52.88650°
Albedo 0.15
Surface temp.
Kelvin
Celsius
min mean max
186 K 227 K 268 K[5]
−87 °C −46 °C −5 °C
Apparent magnitude +1.8 to -2.91[4]
Angular diameter 3.5" 25.1"[4]
Adjectives Martian
Atmosphere
Surface pressure 0.70.9 kPa
Composition 95.72% Carbon dioxide
2.7% Nitrogen
1.6% Argon
0.2% Oxygen
0.07% Carbon monoxide
0.03% Water vapor
0.01% Nitric oxide
2.5 ppm Neon
300 ppb Krypton
130 ppb Formaldehyde
80 ppb Xenon
30 ppb Ozone
10 ppb Methane
Note: This article contains special characters.
Mars (pronounced /ˈmɑrz/) is the fourth planet from the Sun in the Solar System. The planet is named after Mars,...
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