KRC for Europa

Revision as of 15:38, 7 January 2019

Notes

Some parameters are set to realistic values by default, including:

Mat1 = "H2O" which assignes water ice Cp, Density, and Conductivity properties

Mat2 = "H2O" which assignes water ice Cp, Density, and Conductivity properties

ALBEDO = 0.67

PTOTAL = 0 which eliminates the atmosphere (ELEV, TAU, etc. unused)

When running the DaVinci interface, default Mars atmospheric values might be printed on the screen but not effectively used (PTOTAL = 0.)

Command Line Examples

Basic surface temperatures for Europa:

dv>  OUT = krc(lat = 0, INERTIA = 45., body="Jupiter,Europa", bodytype = "minor", ALBEDO = .55, LKofT = "F")

To include the visible and thermal infrared flux from Jupiter, two approaches are possible:

1: Use default built-in parameters, set PFlux = "T", and Lon_Hr

Lon_Hr [0-24] is the surface longitude relative to the sub-Jupiter point, expressed in hours.

When Lon_Hr < 6, the surface point is on the Antijovian hemisphere => No flux contributed.

When 6 < Lon_Hr < 18, the surface point is on the subjoin hemisphere => Flux is contributed (max at Lon_Hr = 12.).

When Lon_Hr > 18, the surface point is on the Antijovian hemisphere => No flux contributed.

dv> OUT  = krc(lat = 0., INERTIA = 70., body = "Jupiter,Europa", bodytype = "minor", ALBEDO = 0.55, PFlux = "T", Lon_Hr = 12., LKofT = "F")

2: Provide values for all the necessary input parameters, and set PFlux = "T" (Default provided for common bodies)

BT_Avg  : Average Brightness Temperature [K]

BT_Min  : Min Brightness Temperature, if diurnal cycle [K]

BT_Max  : Max Brightness Temperature [K]

Dis_AU  : Distance from Sun in AU

Geom_alb  : Geometric Albedo [1]

Mut_Period : Mutual Period [?]

Orb_Radius : Orbiting Radius [km]

Radius  : Radius of the Obiting body [km]

Lon_Hr  : Longitude Hour of the surface point (see above)

dv> OUT  = krc(lat = 0., INERTIA = 70., body = "Jupiter,Europa", bodytype = "minor", ALBEDO = 0.55, PFlux = "T", BT_Avg = 127., BT_Min = 127., BT_Max = 127., Dis_AU = 5.203, Geom_alb = 0.52, Mut_Period = 3.55, Orb_Radius = 670900, Radius = 670900, Lon_Hr = 12., LKofT = "F")

3: Provide Visible and IR flux tables vs. LTST, and set PFlux = "T"

The interface fits sin functions through the table values, and extracts parameters required by KRC (amplitude, phase, etc.). For Europa, this is not the preferred option.

IR: A 2 x n x 1 array with IR flux (1st col.) vs. LTST (2nd col.)

Vis: A 2 x n x 1 array with Vis flux (1st col.) vs. LTST (2nd col.)

dv> OUT  = krc(lat = 0., INERTIA = 70., body = "Jupiter,Europa", bodytype = "minor", ALBEDO = 0.55, PFlux = "T", Lon_Hr = 12., LKofT = "F")

To include an Eclipsed by Jupiter, set Eclipse = "T" and specify the following parameters:

Eclipse = "T" forces an eclipse (Default = "F")

body = "Jupiter,Europa"

Eclipser = "Jupiter_Jupiter" Eclipser name, for Example "Jupiter_Jupiter" or "Mars_Phobos"

Eclipse_Style = 1 because eclipses are assumed to occur daily; see dedicated Eclipse Section [Build Link Here]

Ecl_Cent_Hr: Eclipse central hour [subjovian point => =12.; Antijovian point => =0.]

Bias = 0.0: Eclipse Bias (0 => perfect alignement; 1 => partial eclipse); see dedicated Eclipse Section [Build Link Here]

Date: ???

 dv> OUT = krc(lat = 0., INERTIA = 045., N1 = 32, body = body, bodytype = "minor", N24 = 96, Eclipse = "T", Eclipser="Jupiter_Jupiter", Ecl_Cent_Hr = 12., Bias = 0., Eclipse_Style = 1., Date = 5000.)

Known Issues

1: The default Jupiter_Europa.porb.hdf file has an issue:

EUROPA = load($DV_SCRIPT_FILES + "/krc_support/porb_defaults/Jupiter_Europa.porb.hdf")
EUROPA.planet_flux.Radius = 3121.60  

==> THIS IS THE DIAMETER #REGENERATE .HDF (ONLY EUROPA SEEMS IMPACTED)

2: