The last few images in Robert A. Braeunig's Apollo 11's Translunar Trajectory; and how they avoided the heart of the radiation belts are fascinating and a bit perplexing as discussed in this answer and the comments below it.

This got me wondering what it would take to reconstruct the trajectories of one or more of the Apollo missions from scratch.

  • only the crewed components that NASA tracked carefully because there were people on board
  • primarily outside of Earth's atmosphere where I can numerically integrate trajectories without aerodynamics

Are there raw data out there somewhere? Perhaps range-rate, Doppler etc.? I'm assuming these were recorded and analyzed post mission and written up post-mission, with some tables, but are there large tables of state vectors? Is the raw data available somehow?

Question: If I wanted to reconstruct an entire Apollo mission's crewed spacecraft trajectories, what are the key sources of historical data I'd look for? Where might I find some of them?

There may be some promising leads in answers to Where to look for historical or reconstructed orbit data for early NASA missions - Mercury-Atlas 6 for example. Maybe some day we can get the final answer to Puzzler: Precisely what maximum distance from the Earth did the Apollo 13 astronauts achieve?

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    $\begingroup$ Found them! See edit to my answer. I know what I'll be doing this Christmas holiday... $\endgroup$ – Ludo Nov 30 '19 at 18:11
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    $\begingroup$ I found contemporary data and a trajectory reconstruction for Apollo 17. See updated answer. $\endgroup$ – Ludo Dec 15 '19 at 21:11
  • $\begingroup$ @Ludo okay I'll take a look today, thanks! $\endgroup$ – uhoh Dec 15 '19 at 23:13

To answer the question literally: you'd be looking for NASA Apollo Trajectory (NAT) data files.

The report Apollo Mission 11, Trajectory Reconstruction and Postflight Analysis Volume 1 (PDF) provides a summary for Apollo 11 and mentions that the raw NAT data is available in Volume 2 of the report. I have yet to find Volume 2 though, perhaps because

The listing is not generally distributed but is available from NASA/MSC upon request.

Also Earth Departure Trajectory Reconstruction of Apollo Program Components Undergoing Disposal in Interplanetary Space mentions the availability of NAT data, but without reference.

I requested the document at NASA STI, but:

Thank you for contacting the NASA STI Information Desk. Unfortunately, we do not have the requested document in our repository.

So I asked the author of the paper where to find them. I was thinking about huge data files, but turns out that the available NAT data is a single table that can be found in the Mission Reports. For example, for Apollo 11, it's table 7-II in the Apollo 11 Mission Report.

Trajectory parameters for Apollo 11

(Trajectory parameters for Apollo 11 from Apollo 11 Mission Report)

For Apollo 17, I found "Apollo/Saturn 5 postflight trajectory: AS-512" on NTRS, which contains a wealth of information. Similar documents likely exist for the other Apollo missions, but I have not yet been able to locate them.

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    $\begingroup$ I submitted an inquiry regarding the availability of volume II, see what comes from that. $\endgroup$ – Ludo Nov 24 '19 at 16:01
  • $\begingroup$ I don't believe that Apollo Mission 11, Trajectory Reconstruction and Postflight Analysis Volume 2 in toto is just Table 7-II in another report. It could be that Volume 2 is lost or unavailable due to something like this. But if Volume 1 is 142 pages long, it's hard to believe Volume 2 would be only a single page. However the points in the table certainly appear to be extremely helpful for trajectory reconstruction. Thanks! $\endgroup$ – uhoh Dec 1 '19 at 4:32
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    $\begingroup$ @uhoh I believe that Volume II also contained Best Estimate Trajectories (BET), which I presume to be interpolated data from these tables (i.e. exactly what the reconstruction paper did and what we're trying to do here). Those BET might have been the bulk of Volume II. Given the existence of the Reconstruction paper, Volume II may indeed be lost. $\endgroup$ – Ludo Dec 1 '19 at 8:26
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    $\begingroup$ @Ludo I've found similar trajectory reconstruction report Vol.I for Apollo-8: ibiblio.org/apollo/Documents/19740072902.pdf Same story with Vol.II though (listing in NAT format "available" at request at NASA/MCS Computations and Analysis Division). Vol.I contains some data on what I think is estimated orbital parameters, but not 100% sure. $\endgroup$ – Sergiy Lenzion Jan 16 '20 at 13:41

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