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While trying to find details on the proposed improved Space Shuttle heat shields, I stumbled across a fact I'd forgotten: the orbiters didn't have navigation lights (i.e. red left, green right, white astern or in another useful location for determining orientation).

This surprised me, because as someone who worked in the ISS rendezvous/proximity operations domain, I believe all the spacecraft that I ever had to think about, the ones being grappled at or docking to the US segment of station, had navigation lights (and I believe it was a requirement, which I might actually be able to find a public source for).

This got me wondering: is this anomalous to the ISS domain, maybe an artifact of the desire to see and monitor spacecraft as they approach? Did/do other crewed spacecraft / stations also use them? Or was Space Shuttle the anomaly in not having them?

Erin Anne
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  • this is a little rough right now, but I wanted to get it out of my head before I do some other things today. Related to Have guidelines for red & green navigation light placement on spacecraft been established? If I can find those requirements (I think both CRS and CCDev / whatever CCDev became had them, in part because CCDev requirements grew organically from CRS) I might also be able to give an answer there. – Erin Anne Dec 02 '23 at 21:54
  • I would think that anything using horizontal flight such as the shuttle-types and the Virgin craft should have them. Vertical flight such as the SpaceX returning boosters need not. :twocents: – FlaStorm32 Dec 03 '23 at 02:41
  • @FlaStorm32 ... hovercraft, which can potentially move in any direction, display a flashing yellow light. But they still also display conventional NAV lights to indicate the usual design orientation, and therefor the expected direction of motion. That would seem to be sensible for spacecraft as well. – Woody Dec 03 '23 at 03:35
  • I know vehicles approaching ISS have beacons but I suspect they are just so the ISS crew can see where it is, not to determine orientation. From an ISS point of view orientation only really matters during grappling operations, and by that time it's close enough to be seen with the floodlights on ISS. Of course orientation is important for docking also, but the ISS crew only cares about that as the vehicle gets within 10 meters or whatever the distance is when the ISS crew can trigger an abort if they think the approach doesn't look right. Again I think the floodlights are sufficient for that. – Steve Pemberton Dec 03 '23 at 07:00
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    @StevePemberton I don't see how your suspicions about when the astronauts wanted to know orientation are relevant to my question. I'm also 99% sure from my work experience in rendezvous and proximity operations for the ISS that you're wrong, but the not-relevant-to-the-question matters more. – Erin Anne Dec 03 '23 at 09:38
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    ErinAnne - I was referring to your mention of spacecraft having (or not having) navigation lights for determining spacecraft orientation, as opposed to lights just used to see the spacecraft location. I'm not sure who else would be looking at those lights except ISS crew, which is why I mentioned whether or not orientation lights would be useful to them. By ISS crew "caring" I wasn't inferring that ISS crew preferences decide things like this, I was referring more to ISS program decisions about requirements for visiting spacecraft, which would be based on what would be useful to the ISS crew. – Steve Pemberton Dec 03 '23 at 14:08
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    Looking at a bunch of docking video clips it looks like Cygnus, Dragon, and HTV have red and green lights. ATV seemed to have two white lights, Progress and Soyuz seem to have just a single white light. Kind of hard to determine this because most operations are in orbital daytime especially Progress and Soyuz, but I am getting some screenshots that I can put in an answer. Apollo/Soyuz did not seem to have lights, not sure yet about Apollo/LEM. Soyuz/Mir there are very few video clips. I have had to listen to a lot of Blue Danube because that is what NASA puts on many of their time lapse clips – Steve Pemberton Dec 05 '23 at 16:20

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