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Does the FH upper stage have things like inertial guidance, star cameras, GPS/GNSS, and/or other helpful equipment that would have allowed it to do careful thrust vectoring during the 3rd and final burn, so that in cooperation with possibly data transmitted from the ground, it could have put itself on a carefully controlled trajectory, if there had been a plan to do so?

I'm not asking if it did, I'm asking if the necessary hardware is in place to do so if a plan were in place.

uhoh
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    The FH upper stage is identical to the F9 upper, which routinely delivers satellites where they want to go, so... – Russell Borogove Feb 07 '18 at 15:49
  • Is the FH upper stage designed for several ignitions in zero gravity, even many hours or days after launch? Liquid oxygen will be boiled of completely after some time. – Uwe Feb 07 '18 at 15:49
  • @RussellBorogove I'm not familliar with the details of the 3rd burn. Is it directly comparable to a GTO or GEO insertion, or are there differences that would influence the answer? I just don't know, there was no video! – uhoh Feb 07 '18 at 15:53
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    @Uwe Targeting a well defined orbit happens during the 3rd burn itself, not afterward. Once SECO3 happens, the orbit is defined. – uhoh Feb 07 '18 at 15:58
  • @MichaelK I will take my chances that enough people here understand what targeting a well defined orbit means in this context. The answer that there was no plan (and comments) still gives me pause, and so I'd like to explore the possibility that there might in fact be an interesting orbit planned. The first step is to see if there are any constraints that would prevent a plan, so I've asked this question as part of that. – uhoh Feb 07 '18 at 16:56
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    @uhoh Well I am not interested in what others think you meant. I am wondering what you actually meant when you said "carefully controlled trajectory". This is particularly interesting for me since I offered an answer and got back a comment of the sort "No that is not what I meant". So I deleted the answer and am now asking you to clarify what you meant so the question can be answered properly. What did you mean by "carefully controlled trajectory"? – MichaelK Feb 07 '18 at 17:03
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    @MichaelK Actually, you answered a question completely different than what was actually asked, according to two different people https://i.stack.imgur.com/MazWl.png – uhoh Feb 07 '18 at 17:07
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    @uhoh That was not an answer to the question I have for you here now. Please clarify what you meant when you said "so that [...] it could have put itself on a carefully controlled trajectory". – MichaelK Feb 07 '18 at 17:10
  • @MichaelK I think it will be OK, and that it will be generally clear enough so that a useful answer can be posted. Thanks for your concern, let's see how it goes for now. edit: Thinking about this further, I realized that I've actually intentionally left a bit of leeway here. Sometimes it is better not to over-constrain an question in the beginning. If I said X kilometers or Y milli-radians, that might exclude an otherwise really insightful answer. I've asked a lot of questions in this site, and there are a lot of good answer-writers here. Let's see what happens. – uhoh Feb 07 '18 at 17:30
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    @uhoh So in other words: you had no clear idea what you actually meant. This is all fine. All you need to do is edit the question thus: "How accurately would it have been possible to control the trans-Mars injection burn? What systems did the Falcon Heavy second stage have on board to aid in that endeavour? What ground systems were in operation - or could have been in operation - to help with this?". – MichaelK Feb 07 '18 at 17:47
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    @uhoh Found something you might find interesting: Falcon 9 User's Guide v2.0. Check out Table 4-6 on page no. 27 and section 2.4 on page no. 12. "Avionics include flight computers, Global Positioning System (GPS) receivers, inertial measurement units...". – MichaelK Feb 08 '18 at 11:06
  • @MichaelK That's great! Would you consider writing an answer based on that? It certainly seems that the Roadster is indeed in a well defined heliocentric orbit, passing only about 7 million km from Mars according to https://space.stackexchange.com/a/25079/12102 – uhoh Feb 08 '18 at 11:18
  • Let us continue this discussion in chat. – MichaelK Feb 08 '18 at 11:20
  • @RussellBorogove JPL says clearly as discussed here that they used a state vector calculated from the 2nd stage's GPS and other equipment following the 3rd burn. Considering that it looks like they may pass within 7 million km of Mars in late 2020, I'd say the answer is fairly conclusive now. – uhoh Feb 08 '18 at 11:57

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