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Screenshots below are from Brian May's new music video Brian May - New Horizons (Ultima Thule Mix) [Official Music Video] The beginning shows the launch of a rocket.

I can't tell for sure if this is just CGI or if it is actual footage, but I assume that it is 100% CGI.

Even so, does this rendering represent some actual use of copper on the outside of a launch vehicle? Is there some fact behind the fiction, or is this just weird and inexplicable?

(there are few other technical problems in the video as well)

enter image description here

enter image description here

uhoh
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  • New Horizons launched on a Atlas V. Atlas V rocket bodies are copper colored. Is that what this question is about? https://spaceflightnow.com/atlas/av045/images/a5family_full.jpg – Organic Marble Jan 01 '19 at 13:45
  • @OrganicMarble holy granola!!! Yes that is exactly what this question is about! – uhoh Jan 01 '19 at 13:49
  • @OrganicMarble I'm now very curious why it is like that. I was certain that it was a CGI goof! – uhoh Jan 01 '19 at 13:50

2 Answers2

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It's not copper.

enter image description here

...color of an anodized aluminum surface.

ULA anodizes its Atlas V tank panels. That color results from the specific anodization process they use, combined with the specific aluminum alloy they use.

So, why does anodization produces this specific color? Anodization is a method to increase the thickness of the oxidized layer on a metal surface--for aluminum, that's aluminum oxide, aka corundum. Aluminum is a very soft metal, but corundum is a mineral second only to diamond in hardness. It should be apparent that the Atlas panels are anodized to increase its physical and chemical resistance to damage and wear.

The anodization process not only introduces new chemicals which could bond with the anodizing surface--my source mentions and shows sulfuric, chromic, and nitric acid used--but the process also forms microscopic holes. Perhaps those also cause light to be scattered in a specific way that produces the distinctive color? That's all I can offer--I suspect a more detailed answer is beyond the scope of this stack exchange--Chemistry is probably a good place to ask, though.

It is mentioned that the color matures as the panels sit in the atmosphere post-anodization, so that should help narrow the exact mechanism down.

Source: Tory Bruno. (Want slightly more context? Strongly encourage you to watch the entire video.)

EDIT: In some rather coincidental timing (or perhaps a ULA employee is a Stack Exchange user?), the day after I wrote this answer, ULA tweeted the following confirmation:

"The #AtlasV stages are anodized, which is an electrochemical process that gives the metal surface a corrosion-resistant finish that is bronze in color."

EDIT #2: Tory Bruno himself dropped a juicy tidbit on Twitter today, suggesting that the unique color is caused by a coating of Tiodize applied after anodization. Thanks, Tory!

Anton Hengst
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New Horizons launched on an Atlas V. Atlas V rocket bodies are copper colored.

enter image description here

from here

enter image description here

from here

Quick searches as to why turned up little conclusive information. There are unconvincing discussions on nasaspaceflight.com and reddit. The Atlas V User's Guide confirms that the tanks are made of aluminum, so the speculations about the color being some kind of anodized or other coating are likely correct, but I have not found any information about why it comes out coppery.

Organic Marble
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    larger size: https://apod.nasa.gov/apod/ap020916.html – uhoh Jan 01 '19 at 14:05
  • It looks really electrical to me, like it's a faraday cage against some RFI or EMI weapon https://commons.wikimedia.org/wiki/File:Atlas_V_AV-021_first_stage_erection.jpg – uhoh Jan 01 '19 at 14:10
  • Interesting question, I had never thought about the the 'why'. Incidentally, New Horizons is the only non-shuttle launch I ever saw in person. I was working in the aft compartment of one of the Orbiters when an announcement was made that it was about to go. We ran outside the OPF to watch it. That was a good day at work! – Organic Marble Jan 01 '19 at 14:12
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    a Faraday cage around the fuel tanks and not around the electronics (which are on the second stage) makes little sense. And the aluminium of the tank walls is already a Faraday cage. – Hobbes Jan 01 '19 at 14:14
  • A copper overwrap can protect critical but non-sexy electronics outside of the tank from overloading, getting hot, melting, etc. Copper solders nicely, aluminum is a great conductor in bulk, but connecting pieces of aluminum is a little harder - it's why aluminum wiring in houses is as unpopular as it is. It's just an idea. – uhoh Jan 01 '19 at 14:17
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    I would be extremely surprised if it had anything to do with electronics. – Organic Marble Jan 01 '19 at 14:18
  • There's electrical conductivity, thermal conductivity, the rustic look... not too many other reasons why people would use real copper or copper alloys. – uhoh Jan 01 '19 at 14:28
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    Too bad there is not really available information. I'll ask my former student who works on the CST-100 and see if he knows, but it might be a while. – Organic Marble Jan 01 '19 at 14:31
  • My first guess was Kapton but I couldn’t find any support for it. The top rated comment on the reddit thread seems pretty solid though. – Russell Borogove Jan 01 '19 at 17:03
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    I thought about Kapton as well but keeping it attached seems unlikely. The nsf thread has a post denying the chromate hypothesis. Both are weighted equally imho (zero, because unreferenced). – Organic Marble Jan 01 '19 at 17:49
  • the edit brought this question to the active list, and (as you probably noticed) this Atlas V is painted "rocket white". I'm soooo confused now. – uhoh Jan 02 '19 at 04:05
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    @uhoh it's copper covered with frost. Notice the white is only on the LOX tank. https://i.pinimg.com/originals/d8/4a/60/d84a60c0b534edd9fe449f0ffbc36f17.png – Organic Marble Jan 02 '19 at 04:30