DART v.221201
Add-on for Orbiter2016

REQUIREMENTS
Launch scenario requires:
Falcon9 for Orbiter2016
https://www.orbiter-forum.com/resources/falcon9-for-orbiter2016.291/


INSTALLATION
Extract all files to the root of your Orbiter2016 program directory, preserving the directory structure. This should NOT overwrite anything in the standard Orbiter package.

DIDYMOS & DIMORPHOS MESHES
There are alternative meshes for asteroids Didymos and Dimorphos included in the Meshes/DART/ folder, for use with older versions of D3D9 Graphics Client. Copy-and-paste the meshes into your main Meshes folder.


WHAT'S IN THIS ADD-ON?
The DART and LiciaCube spacecraft, asteroid Didymos and its moonlet Dimorphos.
Launch and post-launch scenarios in "DART" folder.
Scenarios use custom Solar system config file "Sol_DART.cfg" which includes default Orbiter2016 planets and Didymos/Dimorphos.

MISSION
Double Asteroid Redirection Test (DART) is a NASA space mission aimed at testing a method of planetary defense against near-Earth objects (NEOs). It was designed to assess how much a spacecraft impact deflects an asteroid through its transfer of momentum when hitting the asteroid head-on.
More Info:
https://en.wikipedia.org/wiki/Double_Asteroid_Redirection_Test
https://dart.jhuapl.edu/Mission/index.php

NOTES
Press V at T-10 for Falcon9 ascent autopilot to parking orbit.
*** "Dog-leg" Launch! ***
*** Use Falcon9 Control Panel to set target orbit inclination to 64.685 after booster separation.***
Make Earth escape burn manually.
Deploy LiciaCube ~15 days before impact, maintain ~1000km distance trailing DART for flyby of Dimorphos ~165s after impact.
You will need to keep making correction burns for impact targeting right up until 1hr before impact.
(spacecraft perturbed by Earth/Moon, but asteroid is not (uses Keplerian elements for orbit) ?)

IMAGING
Both DART and LiciaCube can take images which are saved as monochrome .bmp in their respective "DART_Images" or "LiciaCube_Images" folder in your Orbiter2016 root folder.
Orbiter FOV is temporarily set to 5deg and HUD cleared.
Images are 2deg FOV at the centre of the vessel internal (cockpit) forward view.
Processing/transmission takes ~1s.


ADD-ON SPACECRAFT INFO
DART:
Low-thrust/high-efficiency "Next-C" Ion engine (Main engine, +Z thrust direction).
12 x RCS engines for rotation (3-axis balanced) and linear thrust (up/down, left/right, forward only).
Linear RCS cosine losses - up/down/left right 30% - forward 13%
Momentum wheels for rotation (3-axis).
LiciaCube stowed for deployment before impact (1m/s separation velocity).
Solar arrays auto sun-tracking after deployment.
DRACO imaging ;-)

Controls:
G = Deploy Solar Arrays
K = Remove DRACO camera cover
J = Jettison LiciaCube (1m/s separation velocity)
Shift+NumPad = Momentum Wheel rotation control
Shift+NumPad5 = Momentum Wheel Kill-Rotation
F7 = Take Image

Data:
Empty Mass                                   500kg
Main Propellant Mass (Xenon)         60kg
RCS Propellant Mass (Hydrazine)   50kg
Main (Ion) Engine Thrust                0.25N
Main (Ion) Engine ISP                  41104Ns/kg
RCS Engine Thrust                           1.0N
RCS Engine ISP                            3200Ns/kg


LICIACUBE:
4 x RCS engines for rotation (3-axis unbalanced) and linear thrust (+Z forward only).
Linear RCS cosine losses 13%
Momentum wheels for rotation (3-axis).
LEIA imaging ;-)

Controls:
G = Deploy Solar Arrays
Shift+NumPad = Momentum Wheel rotation control
Shift+NumPad5 = Momentum Wheel Kill-Rotation
F7 = Take Image

Data:
Empty Mass                                   12kg
Propellant Mass                                2kg
RCS Engine Thrust                      0.05N
RCS Engine ISP                           400Ns/kg


TIMELINE
Launch 24 Nov 2021 06:21:02 UTC
Set target inclination to 64.685 after booster stage separation.
Deploy LiciaCube 11 Sep 2022 23:14 UTC
DART impact with Dimorphos 26 Sep 2022 23:14 UTC
LiciaCube flyby of Dimorphos ~165s after DART impact, distance 56.7km.

ASTEROIDS
Didymos and Dimorphos surfaces are represented by simple mesh - not really landable!
Orbit osculating elements from JPL Horizons.


Cheers!
BrianJ
10 Dec 2022