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Falcon 9 is painted white to avoid heating the liquid oxygen.

Why is Electron not also painted white?

Rocket color-related questions:

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It's not painted black. It just happens to be that color. Omitting paint saves weight. On 2017 May 24, Rocketlab itself tweeted:

Why a black rocket? Carbon composite materials are black! Paint is heavy & adds another process. Plus, doesn't it look beautiful! #ItsaTest


A different question would be why other launchers don't omit paint. I found an unsubstantiated claim that RocketLab uses proprietary coatings for its cryogenic tanks. But it may be just that Electron's relatively small size and thus greater area-to-volume ratio makes paint weight matter more. Conversely, more area-to-volume means more heat transfer, so insulation matters more. Or maybe the frost is enough for both insulation and whiteness? Mere speculation.

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  • $\begingroup$ "Black is a good heat-absorbing color. The fuel that SpaceX uses is liquid oxygen that has to be kept at very low temperatures, as a result, they cannot have the whole rocket be black" - says about Falcon 9 în this answer - space.stackexchange.com/questions/29771/… $\endgroup$
    – Joe Jobs
    Nov 2 '20 at 22:19
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    $\begingroup$ @joeJobs SpaceX uses subcooled LOX, so they are, perhaps, more temperature sensitive. If you use boiling-point LOX, you can just feed the boiloff with no ill effect. $\endgroup$
    – Tristan
    Nov 2 '20 at 22:54
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    $\begingroup$ I've added Is the mass of paint relevant in rocket design? and Could a shiny metallic fairing have some engineering advantage? Disadvantage? to the links in the question, you may be able to find additional supporting information in their answers. $\endgroup$
    – uhoh
    Nov 2 '20 at 23:17
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    $\begingroup$ I won't hunt down substantiation for a mere comment, but even on bare aluminum hull sailboats, paint mass matters when you're racing. $\endgroup$ Nov 3 '20 at 4:32
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    $\begingroup$ Note that the F9 interstage is also black for the same reason: it is not painted and made of carbon composites. $\endgroup$ Nov 3 '20 at 7:05

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