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This is a reference mission timeline, used for costing, feasibility studies, and mission analysis. The final mission design may be quite different.
The trajectory and landing site are based on the Apollo 16 flight profile. Apollo 16 landed near Descartes Crater in April 1972. The mission profile assumes we loiter in Earth orbit for two days to stack and check out the vehicle at the start of the flight.
Launch to Low Earth Orbit
Date & Time Delta T Velocity Delta V Applied
Event Phase Complete Sec ft/sec ft/sec to...
---------------- -------------- ------- -------- ------- -------
Launch 4/08:00:00 0 0 0
LEO Insertion 4/08:11:57 717 25604 ~35000 Stack
Flight to the Moon
Date & Time Delta T Velocity Delta V Applied
Event Phase Complete Sec ft/sec ft/sec to...
---------------- -------------- ------- -------- ------- -------
Translunar Injection 6/08:11:57 172800 25631 27 Stack
TLI Burn Termination 6/08:17:32 335 35649 10018 Stack
Lunar Orbit Operations
Date & Time Delta T Velocity Delta V Applied
Event Phase Complete Sec ft/sec ft/sec to...
---------------- -------------- ------- -------- ------- -------
LUNO Insertion 8/22:03:20 222348 2807 Stack
Descent Orbit Init 9/12:14:12 51052 5486 -
DOI burn termination 9/12:14:36 24 5280 206 Stack
Undock and sep 10/05:52:13 63457 - -
LTV Lunar Orbit Circularization
Date & Time Delta T Velocity Delta V Applied
Event Phase Complete Sec ft/sec ft/sec to...
---------------- -------------- ------- -------- ------- -------
LTV circ. burn Init 10/07:20:27 5294 5724 -
LTV circ. burn term 10/07:20:32 5 5344 100 LTV
Landing on the Moon
Date & Time Delta T Velocity Delta V Applied
Event Phase Complete Sec ft/sec ft/sec to...
---------------- -------------- ------- -------- ------- -------
Descent ignition 10/08:13:23 3171 5571 - Desc
High gate 10/08:22:43 560 355 -
Low gate 10/08:24:05 82 80 -
Vertical descent 10/08:24:45 40 10 -
Landing 10/08:25:24 39 0 6696 Desc
LTV Lunar Orbit Establishment
Date & Time Delta T Velocity Delta V Applied
Event Phase Complete Sec ft/sec ft/sec to...
---------------- -------------- ------- -------- ------- -------
LTV plane change #1 12/14:07:30 193326 5356 - LTV
Burn termination 12/14:07:39 9 5355 159 LTV
Lunar Surface Operations
Lunar surface 20/08:25:24 864000 - - operations
Ascent and Rendezvous
Date & Time Delta T Velocity Delta V Applied
Event Phase Complete Sec ft/sec ft/sec to...
---------------- -------------- ------- -------- ------- -------
Ascent stage liftoff 20/08:25:24 0 - Asc
Insertion 20/08:25:24 434 5339 6048 Asc
Rendezvous - TPI 20/08:32:38 2820 5339 50 Asc
Braking 20/09:19:38 2453 5339 33 Asc
Docking 20/10:00:31 1184 5339 - Asc
Transearth Injection
Date & Time Delta T Velocity Delta V Applied
Event Phase Complete Sec ft/sec ft/sec to...
---------------- -------------- ------- -------- ------- -------
TEI Prep 20/10:20:15 7200 5339 -
Transearth injection 20/10:20:15 - 5339 -
TEI Burn termination 22/10:20:15 150 8521 3212 LTV/Asc
Return to Earth
Date & Time Delta T Velocity Delta V Applied
Event Phase Complete Sec ft/sec ft/sec to...
---------------- -------------- ------- -------- ------- -------
LEO Arrival 172800 36176 -
LEO Rendezvous 25604 10572 LTV/Asc
Definitions
Notes
The time listed is what the clock reads at the end of each mission phase. Delta T is the elapsed time for that mission phase, in seconds.
Velocity is measured relative to Earth up to Translunar Injection at the beginning of the mission, and after Transearth Injection at the end of the mission. Otherwise, velocity is relative to the moon.
Velocities are given in feet per second. To convert to meters per second, multiply feet per second by 0.3048 (exactly).
The date for this timeline is tentative -- proper moon phasing is not considered. We would like to land on the moon at Angus Bay just after sunrise and spend an entire lunar day (two weeks on earth) on the surface.
This mission timeline assumes we use rockets, rather than an aerobrake, to slow the spacecraft to Earth orbital velocity when we get home. This maneuver uses almost 9,000 lbs of fuel; but the additional weight of a spacecraft capable of atmospheric braking might be considerably more. Compare, for example, the anticipated weight of the Lunar Transfer Vehicle at about 7,000 lbs total dry weight (command module plus service module) to the Apollo 16 command module's weight of 27,000 lbs.
Velocity and delta V numbers don't add up in some places because the value for delta V include effects not related to changing the vehicle's gross velocity. For example, the delta V budget for braking and rendezvous numbers might be expended in any direction to match orbit, so it does not affect nominal velocity. Delta V for ascent from the earth and the moon includes inefficiencies such as thrusting against the lunar gravity before achieving orbital velocity as well as altitude change, so the total delta V required for this flight is greater than the final orbital velocity.
The masses of the spaceraft and the fuel required for each engine burn are available in section 4.2 of the Artemis Data Book. Detailed mass properties are in the system engineering data, in section 4.2.0.1.
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