Lunar Case 8c: NRHO - Delta Radius
Scenario 8c tests Keplerian propagation of the Apollo LM model in a low-fidelity 8x8 GRAIL gravity field with Sun and Earth perturbations. This case uses a Near-rectilinear Halo Orbit (NRHO) and tests the sensitivity of Scenario 8 to changes in initial conditions.
Constants and models
The gravitational constant is defined from the GRAIL model specified in the table below. The ephemerides are: DE440. Time is expressed in UTC. Although test case initial conditions may be in the future, the following constants are used: TAI − UTC = 37 sec; DUT1 = 0.0 sec Low-Fidelity GRAIL uses the GRAIL gravity model of degree and order 8 (i.e. 8x8 GRAIL).
Initial Conditions
| Scenario | Lunar Case 8c: NRHO - Delta Radius | |||
|---|---|---|---|---|
| Body | Apollo Model | |||
| Orientation | Major axis is approximately along the velocity vector quaternionWrtMi = [0.646080387557766 0.334383101748747 0.685546322693561 0.0281835682522564] Where the components are ordered [W X Y Z]' |
|||
| Rotation | [0.001, 0, 0] deg/s To be specified in inertial frame. Body angular rate w.r.t. MI expressed in body |
|||
| Gravitation | Low-Fidelity GRAIL | Gravity Gradient Effects | Off | |
| Sun/Earth Perturbations | On | Duration | 604,800 s | |
| Output Interval | 60 s | Output Format | CSV | |
| Initial states | ||||
| Time | 2026-1-28 6:42:03.51 UTC corresponds to output j2000UtcTime_s J2000 epoch of January 1.5, 2000 = -2451545.0 days Using 37 leap seconds j2000TtTime_s = j2000UtcTime + 32.184 + 37 = j2000UtcTime + 69.184 (s) Note that delta UT1/UTC is not relevant for checkcase and is thus not specified |
|||
| Frame | Planet-Centered Inertial | |||
| Position (m) |
miPosition_m_X miPosition_m_Y miPosition_m_Z |
-5838149.197823560 2538928.800553022 1055567.832616975 |
||
| Velocity (m/s) |
miVelocity_m_s_X miVelocity_m_s_Y miVelocity_m_s_Z |
-685.576059820879546 751.297639180154464 -621.913991301902946 |
||
Latest Results
Posted :
| Sim | Raw Data Link |
|---|
Interactive Plots
Posted :
Note: pp_euler variables are Euler angles automatically calculated from sim provided quaternions.
A link to the conversion used can be accessed from the References menu in the navigation bar.
Note: All quaternions are modified to be scalar positive.
Load Data
A CSV file matching the format of the files found in the "Latest Results" table can be loaded from the input below to compare to the results from the Lunar Check Case study, this is a temporary load in your browser only.