EnVision Example Trajectories
================================

VERSION:        3.0
CREATION_DATE:  2020/06/10
ORIGINATOR:     ESA/ESOC (P. Munoz)


CONTENT: Trajectory files in OEM (*.oem) and Spice Kernel (*.bsd) formats
         covering the full mission duration consistent to the latest mission
         baseline:
  
  - ESC_T4_2032_NorthVOI: launch into direct escape at -5.0 deg declination
                          and Venus Orbit Insertion over the Northern
                          hemisphere.


NOTES:

  - Trajectory data is consistent with JPL planetary ephemerides DE-432.
  
  - Aerobraking phase is not realistically modelled. Drag effect is emulated
    as several impulsive delta-Vs distributed throughout the aerobraking
    duration.
  
  - Science orbit time span (2035/06/15 - 2039/06/14) covering the nominal
    mission duration of 6 Venus cycles.
  
  - Venus gravity field expansion to 40x40 degree and order used for
    propagation of the science orbit.


VERSION:        2.0
CREATION_DATE:  2019/07/26 
ORIGINATOR:     ESA/ESOC (P. Munoz)


CONTENT: Trajectory files in OEM (*.oem) and Spice Kernel (*.bsd) formats
         covering the full mission duration for two different scenarios:
  
  - ESC_T2_2032_SouthVOI: launch into direct escape at -3.0 deg declination
                          and Venus Orbit Insertion over the Southern
                          hemisphere.
  
  - HEO_T2_2032_NorthVOI: launch into HEO (310x100,000 km) and
                          Venus Orbit Insertion over the Northern hemisphere.


NOTES:

  - Trajectory data is consistent with planetary ephemeris DE-432.
  
  - Aerobraking phase is not realistic neither in duration nor in dynamic
    modelling.

  - Science orbit time span (2034/11/26 - 2040/03/24) extended to account
    for the uncertainty in the date of aerobraking finalisation.
  
  - Venus gravity field expansion to 40x40 degree and order used for
    propagation of the science orbit.


Contact Information
-----------------------------------------------------------------------------

   If you have any questions regarding this file contact the ESA SPICE
   Service at ESAC:

           Alfredo Escalante Lopez
           (+34) 91-8131-429
           spice@sciops.esa.int