Ephemeris and Lambert Algorithms:

Test Cases

ASEN 5519 – Interplanetary Mission Design

Fall, 2006

Introduction

Later in the semester, you will be constructing many porkchop plots to construct interplanetary mission designs to the outer planets. The fundamental building block of a porkchop plot is the solution to Lambert’s Problem. Hence, to be a successful interplanetary mission designer, your Lambert code must be a strong foundation to stand on! The algorithms also require good ephemeris code and good JD converters. This document will provide some test cases to test out your code.

Assumptions!!!

1 AU / 149,597,870 km (Vallado)
Solar Gravitational Parameter / 1.327 124 28 x 1011 km3/(solar sec)2 (Vallado)
1 Day / 86400 seconds

Date to JD Conversion

Date = Nov. 25th, 1978; 4h 30m 0s

JD = 2443837.6875

Date = Sept. 15th, 2006; 10h 00m 20s

JD = 2453993.9169

Date = Jan. 1st, 2007; 0h 00m 00s

JD = 2454101.5

Ephemeris and Lambert Checks:

Planet 1: Earth Planet 2: Mars

Departure JD: 2454367.90000 Arrival JD: 2454577.90000

Transfer Duration: 210.00000 days (1.81440000e+007 seconds)

------

Earth's Position at JD1: [150064539.403983 2267759.896369 -276.754311] km wrt the Sun

Earth's Velocity at JD1: [-0.935067 29.673807 -0.000519] km/s wrt the Sun

Mars' Position at JD2: [-207818935.305987 136713926.487051 7968576.434594] km wrt the Sun

Mars' Velocity at JD2: [-12.404508 -18.175755 -0.076153] km/s wrt the Sun

Spacecraft Velocity at JD1: [-0.075289 33.476420 1.907380] km/s wrt the Sun

Spacecraft Velocity at JD2: [-14.189471 -14.839340 -0.833227] km/s wrt the Sun

Spacecraft V-inf out: [0.859778 3.802612 1.907899] km/s wrt Earth

Spacecraft V-inf in: [-1.784964 3.336414 -0.757073] km/s wrt Mars

C3 at Launch: 18.839158 km^2/s^2 |V-inf| at Arrival: 3.858875 km/s

Planet 1: Earth Planet 2: Venus

Departure JD: 2454367.90000 Arrival JD: 2454577.90000

Transfer Duration: 210.00000 days (1.81440000e+007 seconds)

------

Earth's Position at JD1: [150064539.403983 2267759.896369 -276.754311] km wrt the Sun

Earth's Velocity at JD1: [-0.935067 29.673807 -0.000519] km/s wrt the Sun

Venus' Position at JD2: [108502685.373919 981095.895427 -6248799.806056] km wrt the Sun

Venus' Velocity at JD2: [-0.465174 34.859502 0.504045] km/s wrt the Sun

Spacecraft Velocity at JD1: [23.041751 0.806102 4.344444] km/s wrt the Sun

Spacecraft Velocity at JD2: [34.742706 0.947442 4.007763] km/s wrt the Sun

Spacecraft V-inf out: [23.976818 -28.867706 4.344962] km/s wrt Earth

Spacecraft V-inf in: [35.207880 -33.912060 3.503718] km/s wrt Venus

C3 at Launch: 1427.110960 km^2/s^2 |V-inf| at Arrival: 49.009169 km/s

Planet 1: Earth Planet 2: Venus

Departure JD: 2454257.00000 Arrival JD: 2454402.00000

Transfer Duration: 145.00000 days (1.25280000e+007 seconds)

------

Earth's Position at JD1: [-40907159.776698 -146166176.029225 2524.752269] km wrt the Sun

Earth's Velocity at JD1: [28.201602 -8.140052 0.000094] km/s wrt the Sun

Venus' Position at JD2: [21214945.229277 105654723.068676 221755.525408] km wrt the Sun

Venus' Velocity at JD2: [-34.453939 6.720951 2.080517] km/s wrt the Sun

Spacecraft Velocity at JD1: [26.151206 -6.439026 -0.747977] km/s wrt the Sun

Spacecraft Velocity at JD2: [-36.925365 8.695987 1.053181] km/s wrt the Sun

Spacecraft V-inf out: [-2.050396 1.701026 -0.748071] km/s wrt Earth

Spacecraft V-inf in: [-2.471426 1.975036 -1.027336] km/s wrt Venus

C3 at Launch: 7.657223 km^2/s^2 |V-inf| at Arrival: 3.326279 km/s

Planet 1: Earth Planet 2: Jupiter

Departure JD: 2454208.00000 Arrival JD: 2455648.00000

Transfer Duration: 1440.00000 days (1.24416000e+008 seconds)

------

Earth's Position at JD1: [-133790709.833879 -68187957.669580 1327.392275] km wrt the Sun

Earth's Velocity at JD1: [13.041750 -26.652198 0.000422] km/s wrt the Sun

Jupiter's Position at JD2: [713873801.986079 196242257.471874 -16779211.940408] km wrt the Sun

Jupiter's Velocity at JD2: [-3.622026 13.220510 0.026292] km/s wrt the Sun

Spacecraft Velocity at JD1: [9.811753 -37.136284 -4.217053] km/s wrt the Sun

Spacecraft Velocity at JD2: [-6.852424 6.013385 0.951383] km/s wrt the Sun

Spacecraft V-inf out: [-3.229997 -10.484087 -4.217474] km/s wrt Earth

Spacecraft V-inf in: [-3.230398 -7.207125 0.925092] km/s wrt Jupiter

C3 at Launch: 138.136042 km^2/s^2 |V-inf| at Arrival: 7.951975 km/s

Planet 1: Earth Planet 2: Saturn

Departure JD: 2454400.00000 Arrival JD: 2456850.00000

Transfer Duration: 2450.00000 days (2.11680000e+008 seconds)

------

Earth's Position at JD1: [125312162.328009 80094189.561700 -1620.778825] km wrt the Sun

Earth's Velocity at JD1: [-16.527724 24.988254 -0.000417] km/s wrt the Sun

Saturn's Position at JD2: [-916332981.031387 -1169747308.621389 56877707.789551] km wrt the Sun

Saturn's Velocity at JD2: [7.056768 -5.985045 -0.176776] km/s wrt the Sun

Spacecraft Velocity at JD1: [-26.139293 30.300255 -4.576393] km/s wrt the Sun

Spacecraft Velocity at JD2: [3.406155 -2.080308 0.414463] km/s wrt the Sun

Spacecraft V-inf out: [-9.611569 5.312002 -4.575976] km/s wrt Earth

Spacecraft V-inf in: [-3.650613 3.904737 0.591239] km/s wrt Saturn

C3 at Launch: 141.539187 km^2/s^2 |V-inf| at Arrival: 5.378058 km/s