Eclipses
(→Artificial Eclipses) |
|||
Line 59: | Line 59: | ||
SEE IF fort46 file is being written | SEE IF fort46 file is being written | ||
− | |||
− | |||
− | |||
− | |||
− | |||
− | |||
− | |||
− | |||
==Definition of Bias== | ==Definition of Bias== |
Revision as of 14:03, 30 January 2020
KRC differentiates daily eclipses, such as those experiences by Galilean satellites, from rare eclipses, for example partial solar eclipse by Phobos as seen from the surface of Mars.
Contents |
Daily Eclipses
Daily eclipses are recurring events modeled identically for each day of the year. To include a daily, eclipse, a few parameters must be specified:
- Eclipse #forces an eclipse (Default = "F")
- Eclipser #Eclipser name, for example "Mars_Mars" for a Phobos or Deimos study
- Ecl_Cent_Hr #Eclipse central hour [0-24]
- Bias #Eclipse Bias (0 => perfect alignement; 1 => partial eclipse); see below for a graphical definition of Bias
- Eclipse_Style = 1 #=1 Forces daily eclipses
- Date #[ J2000 date of Rare eclipse ] Unused by the KRC for rare eclipses (but required / need to test?)
Example: include a solar eclipse by Mars on Phobos using standard Phobos/Mars orbital properties:
- Eclipse = "T" #forces an eclipse (Default = "F")
- Eclipser = "Mars_Mars" #Eclipser name
- Ecl_Cent_Hr = 12. #Eclipse central hour
- Bias = 0.0 #Eclipse Bias (0 => perfect alignement; 1 => partial eclipse)
- Eclipse_Style = 1
- Date = 0.
out = krc( lat = 12. ,INERTIA = 50. ,body = "Mars,Phobos", LKofT = "T", Eclipse = Eclipse, Eclipser = Eclipser, Ecl_Cent_Hr = Ecl_Cent_Hr, Bias = Bias, Eclipse_Style = Eclipse_Style,Date = Date)
When working with eclipses, it may be beneficial to increase the time resolution of the output by increasing N24
out = krc( lat = 12. ,INERTIA = 50. ,body = "Mars,Phobos", LKofT = "T", Eclipse = Eclipse, Eclipser = Eclipser, Ecl_Cent_Hr = Ecl_Cent_Hr, Bias = Bias, Eclipse_Style = Eclipse_Style,Date = Date, N24 = 96 * 100)
Rare Eclipses
Rare eclipses are one time events. To include a rare, eclipse, a few parameters must be specified:
Eclipse #forces an eclipse (Default = "F")
- Eclipser #Eclipser name, for example "Mars,Phobos" for a partial solar eclipse by Phobos
- Ecl_Cent_Hr #Eclipse central hour [0-24]
- Bias #Eclipse Bias (0 => perfect alignement; 1 => partial eclipse); see below for a graphical definition of Bias
- Eclipse_Style = 2 #=2 Forces rare eclipses
- Date #[ J2000 date of Rare eclipse ]
DEVELOP AN EXAMPLE HERE
SEE IF fort46 file is being written
Definition of Bias
Eclipses require to provide the "Bias", defined as Sun/Eclipsed Body center line closest approach to the Occulting Body center, as a fraction of the Occulting Body radius; + is North.
See the figure below: the Bias quantifies how "long" or how "perfect" an eclipse is, and is quantified for Earth as "Gamma" (here Bias = -0.3014).
Input Files
Earth/Moon
Mars/Phobos
Europa/Jupiter
Known Issues
1. If Ecl_Cent_Hr is provided, an eclipse will be simulated even if Eclipse is set to "F"