The Martian Atmosphere

MARTIAN ATMOSPHERE


Surface pressure:  6.36 mb at mean radius (variable from 4.0 to 8.7 mb depending on season)  
                   [6.9 mb to 9 mb (Viking 1 Lander site)]
Surface density:  ~0.020 kg/m³
Scale height:  11.1 km
Total mass of atmosphere:  ~2.5 x 10¹⁶ kg
Average temperature:  ~210 K (-63 C)
Diurnal temperature range:  184 K to 242 K (-89 to -31 C) (Viking 1 Lander site)
Wind speeds:  2-7 m/s (summer), 5-10 m/s (fall), 17-30 m/s (dust storm) (Viking Lander sites)
Mean molecular weight:  43.34 g/mole 
Atmospheric composition (by volume): 
    Major:        Carbon Dioxide (CO₂) - 95.32%; Nitrogen (N₂) - 2.7%
                  Argon (Ar) - 1.6%; Oxygen (O₂) - 0.13%; Carbon Monoxide (CO) - 0.08% 
    Minor (ppm):  Water (H₂O) - 210; Nitrogen Oxide (NO) - 100; Neon (Ne) - 2.5;
                  Hydrogen-Deuterium-Oxygen (HDO) - 0.85; Krypton (Kr) - 0.3; Xenon (Xe) - 0.08

SOURCE: http://nssdc.gsfc.nasa.gov/planetary/factsheet/marsfact.html

Physical Properties of Martian Atmosphere in SI Units
(Viking 1 Lander site, daytime temperature)
Altitude
(meters) Temperature
(K) Pressure
(Pa) Density
(kg/m³)

-7,000 249 1.31E+3 2.74E-2

-6,000 248 1.20E+3 2.52E-2

-5,000 247 1.10E+3 2.31E-2

-4,000 246 1.00E+3 2.12E-2

-3,000 245 9.16E+2 1.94E-2

-2,000 244 8.37E+2 1.78E-2

-1,000 243 7.65E+2 1.64E-2

0 242 6.99E+2 1.50E-2

1,000 241 6.39E+2 1.38E-2

2,000 240 5.84E+2 1.27E-2

3,000 239 5.34E+2 1.16E-2

4,000 238 4.88E+2 1.07E-2

5,000 237 4.46E+2 9.79E-3

6,000 236 4.07E+2 8.98E-3

7,000 234 3.72E+2 8.26E-3

8,000 232 3.40E+2 7.64E-3

9,000 230 3.11E+2 7.05E-3

10,000 228 2.84E+2 6.50E-3

15,000 216 1.81E+2 4.36E-3

20,000 205 1.16E+2 2.93E-3

25,000 194 7.37E+1 1.97E-3

30,000 183 4.70E+1 1.34E-3

40,000 161 1.91E+1 6.18E-4

For h < 7,000
T = -31 - 0.000998 h
p = 0.699 × e^{-0.00009 h}
= p / (0.1921 × (T + 273.15))
For h > 7,000 (to about 46 km)
T = -23.4 - 0.00222 h
p = 0.699 × e^{-0.00009 h}
= p / (0.1921 × (T + 273.15))
h = altitude (m), T = temperature (^oC), p = pressure (kPa), = density (kg/m³)

SOURCE: http://www.grc.nasa.gov/WWW/K-12/airplane/atmosmrm.html

Physical Properties of Martian Atmosphere in SI Units (Viking 1 Lander site, daytime temperature)
Altitude (meters)	Temperature (K)	Pressure (Pa)	Density (kg/m³)

-7,000	249	1.31E+3	2.74E-2
-6,000	248	1.20E+3	2.52E-2
-5,000	247	1.10E+3	2.31E-2
-4,000	246	1.00E+3	2.12E-2
-3,000	245	9.16E+2	1.94E-2
-2,000	244	8.37E+2	1.78E-2
-1,000	243	7.65E+2	1.64E-2
0	242	6.99E+2	1.50E-2
1,000	241	6.39E+2	1.38E-2
2,000	240	5.84E+2	1.27E-2
3,000	239	5.34E+2	1.16E-2
4,000	238	4.88E+2	1.07E-2
5,000	237	4.46E+2	9.79E-3
6,000	236	4.07E+2	8.98E-3
7,000	234	3.72E+2	8.26E-3
8,000	232	3.40E+2	7.64E-3
9,000	230	3.11E+2	7.05E-3
10,000	228	2.84E+2	6.50E-3
15,000	216	1.81E+2	4.36E-3
20,000	205	1.16E+2	2.93E-3
25,000	194	7.37E+1	1.97E-3
30,000	183	4.70E+1	1.34E-3
40,000	161	1.91E+1	6.18E-4
For h < 7,000 T = -31 - 0.000998 h p = 0.699 × e^{-0.00009 h} = p / (0.1921 × (T + 273.15)) For h > 7,000 (to about 46 km) T = -23.4 - 0.00222 h p = 0.699 × e^{-0.00009 h} = p / (0.1921 × (T + 273.15)) h = altitude (m), T = temperature (^oC), p = pressure (kPa), = density (kg/m³)
SOURCE: http://www.grc.nasa.gov/WWW/K-12/airplane/atmosmrm.html

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