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Reference Case 16:  .5 A.U. x 45° Inclination Heliocentric Orbit

Mission Description

  • Earth Departure Conditions, January 1, 2000:
    • Delta III Launch Vehicle (launch vehicle model number 50)
    • V infinity = 1.95 km/s (optimized)
    • Launch vehicle adapter mass (kadp) as a fraction of initial mass is 0.05
    • Or, fix initial mass at 2204 kg and use V infinity above
  • Target orbit:
    • Semimajor Axis = .5 AU
    • Eccentricity = 0
    • Inclination = 45 degrees
    • Longitude of Ascending Node = 183.57177 degrees
    • Argument of Periapsis = 0 degrees
    • Mean Anomaly of Epoch = 0 degrees
  • Circular coplanar ephemeris option (efemr=1, eopt=3)
  • Solar array model = “high”
  • Propulsion System efficiency

 equation

  • bb=0.768702649
  • dd=1019.830595
  • Specific Impulse constant at 5316.37 seconds (optimized)
  • Tankage Fraction kt is 0.1, fraction of propellant mass
  • Propulsion & Power System Mass 30 kg/kW
  • Power at 1 AU is 40 kW
  • Maximum allowed power is 50 kW
  • Spacecraft Housekeeping Power =0.25 kW
  • Flight Time is 630.6 days (optimized)
  • Originally modeled using VARITOP (Solarpolar.inp)

 

Additional Mission Options

A. 0.5-au NEP polar imager @ 45 degrees. Same as Reference Mission 16 except:

  • Constant Power, 193.4 kW (optimized)
  • Spiral escape from 800 km altitude circular orbit
  • Initial Mass 10,250 kg
  • Propulsion & Power System Mass: (alpha relationship TBD)
    • alfa(1:2)=10.137,33623,
    • alfa(5)=3.37,
    • alfa(7:8)=2672.6,110.36,
  • Specific Impulse constant at 6406.7 seconds (optimized)
  • Heliocentric Flight Time is 863.7 days (optimized)
  • Originally modeled using VARITOP (neppolar.inp)

B. 1 AU polar orbiter (90° to ecliptic)
C. Solar Polar Rendezvous

  • Launch from Earth on Julian date 2451452.5 (Oct. 1, 1999) -- fixed
  • Rendezvous with Target orbit on Julian Date 2452852.5 (Aug. 1, 2003)
  • Target Orbit: a=1.0AU, e=0.98, i = 90°, RAAN= 10°, argp=0°, MA = 345°
  • Launch Vehicle – Delta 7925-9.5; 10% contingency
  • Launch V∞ magnitude, direction: free
  • Propulsion Model: Nstar Engine G (up to 4 Engines)
  • Power Model: seps solar array, P0 = free,
  • Objective function: final mass
  • Originally modeled using SEPTOP

Input/Output files

Copernicus20060313.zip (download)

MALTO4_4.zip (download)

Mystic9_0_0.zip (download)

VARITOPv10_57.zip (download)

SEPTOP11_136.zip (download)

All Reference Case 16: 5 A.U. x 45° Inclination Heliocentric Orbit Files (download zip)