Artemis: From Gateway to Low Lunar Orbit

One concept Gateway may be in a polar orbit with an apolune of 70,000 km and perilune of 3,000 km. One concept is for the lander and Orion to meet at Gateway. Our alternative is for Artemis to stay in a low lunar orbit and be met there by Orion, the cargo transfer vehicle and the tanker. There are many orbit maneuver sequences that will get us from Gateway to our 15 km altitude orbit. A simple one is shown below. We first lower apogee to 3,000 km we then do a Hohmann transfer from the 3,000 km orbit to the 1753 km orbit (that is 15 km altitude). The maneuver to lower apogee is shown below.

The delta-v for the first maneuver is 0.49 km/s and for the Hohmann transfer is 0.39 km/s.

While in low lunar orbit in between landings the lunar lander will do high resolution photo surveys of the surface. These will be used to train the neural network for landing navigation.

Lunar Cube Module for 2016.1

We are adding the Lunar Cube Module in 2016.1 to our CubeSat Toolbox for MATLAB! It allows users to analyze and simulateCubeSats in lunar transfer and lunar orbit. It includes a new dynamical model for CubeSats that includes:

  • Earth, Moon and Sun gravity based on the JPL ephemerides
  • Spherical harmonic lunar gravity model
  • Reaction wheels
  • Thrusters
  • Power generation from solar panels
  • Battery energy storage
  • Variable mass due to fuel consumption
  • Solar pressure disturbances
  • Lunar topographic model
  • New graphics functions for lunar orbit operations
  • Lunar targeting function
  • Lunar mission control function for attitude control and orbit control

The module includes a script with a simulation of a 6U Cubesat leaving Earth orbit and reaching the moon. The following figure shows the Earth to Moon trajectory.

LunarTrajectory

This figure shows the transfer orbit near the moon. The lunar topography is exaggerated by a factor of 10 to make it visible. It is based on Clementine measurements.

LunarEncounter

Here are results from the new LunarTargeting function. It finds optimal transfers to lunar orbits. The first shows the transfer path to the Moon’s sphere of influence.

Test21

The next shows the lunar hyperbolic orbit. In this case the transfer is into a high inclination lunar orbit.

Test22

Contact us for more information!