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Kepler’s war with Mars

Kepler’s War with Mars

Mars Fact Sheet

from nasa:

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

Mars/Earth Comparison

Bulk parameters

                                   Mars           Earth     Ratio (Mars/Earth)

Mass (10²⁴ kg)                     0.64185         5.9736         0.107

Volume (10¹⁰ km³)                 16.318         108.321          0.151

Equatorial radius (km)              3396.2         6378.1          0.532

Polar radius (km)                  3376.2         6356.8          0.531

Volumetric mean radius (km)        3389.5         6371.0          0.532

Core radius (km)                   1700           3485            0.488

Ellipticity (Flattening)           0.00589         0.00335        1.76

Mean density (kg/m³)               3933           5515            0.713

Surface gravity (m/s²)             3.71            9.80           0.379

Surface acceleration (m/s²)        3.69            9.78           0.377

Escape velocity (km/s)             5.03           11.19           0.450

GM (x 10⁶ km³/s²)                  0.04283         0.3986         0.107

Bond albedo                        0.250           0.306          0.817

Visual geometric albedo            0.170           0.367          0.463

Visual magnitude V(1,0)           -1.52           -3.86             -

Solar irradiance (W/m²)          589.2          1367.6            0.431

Black-body temperature (K)       210.1           254.3            0.826

Topographic range (km)               30             20            1.500

Moment of inertia (I/MR²)          0.366           0.3308         1.106

J₂ (x 10^-6)                     1960.45         1082.63           1.811

Number of natural satellites          2              1

Planetary ring system                No             No

Orbital parameters

                                   Mars           Earth     Ratio (Mars/Earth)

Semimajor axis (10⁶ km)          227.92          149.60           1.524

Sidereal orbit period (days)     686.980         365.256          1.881

Tropical orbit period (days)     686.973         365.242          1.881

Perihelion (10⁶ km)              206.62          147.09           1.405

Aphelion (10⁶ km)                249.23          152.10           1.639

Synodic period (days)            779.94             -               -

Mean orbital velocity (km/s)      24.13           29.78           0.810

Max. orbital velocity (km/s)      26.50           30.29           0.875

Min. orbital velocity (km/s)      21.97           29.29           0.750

Orbit inclination (deg)            1.850           0.000            -

Orbit eccentricity                 0.0935          0.0167         5.599

Sidereal rotation period (hrs)    24.6229         23.9345         1.029

Length of day (hrs)               24.6597         24.0000         1.027

Obliquity to orbit (deg)          25.19           23.44           1.075

Mars Observational Parameters

Discoverer:      Unknown

Discovery Date:  Prehistoric

Distance from Earth

        Minimum (10⁶ km)           55.7

        Maximum (10⁶ km)          401.3

Apparent diameter from Earth

        Maximum (seconds of arc)   25.1

        Minimum (seconds of arc)    3.5

Mean values at opposition from Earth

        Distance from Earth (10⁶ km)         78.39

        Apparent diameter (seconds of arc)   17.9

        Apparent visual magnitude            -2.0

Maximum apparent visual magnitude            -2.91

Mars Mean Orbital Elements (J2000)

Semimajor axis (AU)                  1.52366231

Orbital eccentricity                 0.09341233

Orbital inclination (deg)            1.85061

Longitude of ascending node (deg)   49.57854

Longitude of perihelion (deg)      336.04084

Mean Longitude (deg)               355.45332

North Pole of Rotation

Right Ascension: 317.681 - 0.106T

Declination    :  52.887 - 0.061T

Reference Date : 12:00 UT 1 Jan 2000 (JD 2451545.0)

T = Julian centuries from reference date

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

Satellites of Mars

                                    Phobos         Deimos

Semi-major axis* (km)                9378          23459

Sidereal orbit period (days)        0.31891        1.26244

Sidereal rotation period (days)     0.31891        1.26244

Orbital inclination (deg)            1.08           1.79

Orbital eccentricity                0.0151         0.0005

Major axis radius (km)                13.4            7.5

Median axis radius (km)               11.2            6.1

Minor axis radius (km)                 9.2            5.2

Mass (10¹⁵ kg)                       10.6            2.4

Mean density (kg/m³)                 1900           1750

Geometric albedo                      0.07           0.08

Visual magnitude V(1,0)             +11.8          +12.89

Apparent visual magnitude (V₀)        11.3           12.40

*Mean orbital distance from the center of Mars.

Phobos

http://nssdc.gsfc.nasa.gov/image/planetary/mars/f854a81-3.jpg

Deimos

http://nssdc.gsfc.nasa.gov/imgcat/html/object_page/vo2_428b60.html

http://nssdc.gsfc.nasa.gov/imgcat/html/mission_page/MS_Viking_2_Orbiter_page1.html

Sons of War:

Fear and Panic

Phobos

http://nssdc.gsfc.nasa.gov/photo_gallery/photogallery-mars.html#satellites

Deimos

http://nssdc.gsfc.nasa.gov/imgcat/html/object_page/vo2_413b83.html

Deimos - Viking 2 Orbiter

High-resolution view of Mars' moon Deimos from 30 km

This is one of the highest resolution images ever taken from an orbiting or flyby spacecraft. This Viking 2 Orbiter image shows the surface of Mars' moon Deimos from a distance of 30 km. The image covers an area 1.2 km by 1.5 km and features as small as 3 meters across can be seen. Note many of the craters are covered over by a layer of regolith estimated to be about 50 meters thick. Large blocks, 10 to 30 meters across, are also visible. North is at 11:30.

http://nssdc.gsfc.nasa.gov/imgcat/html/object_page/vo2_423b63.html

Phobos - Viking 1 Orbiter

Mars' moon Phobos and Stickney crater from 1600 km

Viking 1 Orbiter global view of the Martian satellite Phobos. The 10 km diameter Stickney crater is at the left, centered at 5 S, 55 W. The Mars facing point is at the bottom center of Phobos, and the north pole is at about 1:00 from this point. Radiating grooves and crater chains can be seen around Stickney. Phobos is roughly 20 km across in this image.

http://nssdc.gsfc.nasa.gov/imgcat/html/object_page/vo1_357a64.html

Page 1

Keplers Elliptical Orbit .

Page 2

Orbit Data.

Page 3

Mars Fact Sheet. (nasa)