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On 27/09/2020 06:37, Adrian Tymes wrote:<br>
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<div dir="ltr">On Fri, Sep 25, 2020 at 11:38 AM Dave Sill via
extropy-chat <<a
href="mailto:extropy-chat@lists.extropy.org"
moz-do-not-send="true">extropy-chat@lists.extropy.org</a>>
wrote:<br>
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<div dir="ltr">On Fri, Sep 25, 2020 at 12:50 PM Adrian
Tymes via extropy-chat <<a
href="mailto:extropy-chat@lists.extropy.org"
target="_blank" moz-do-not-send="true">extropy-chat@lists.extropy.org</a>>
wrote:<br>
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<div dir="ltr">If these habitats are, say,
cylinders 2 km wide, to allow them to be spun up
to 1 G, that's enough of a technical (and
imposed-by-human-biology) standard that people
might not want to mess with it. 2 km wide
suggests maybe 5 km long maximum, for structural
stability.</div>
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<div>What about rotational stability? Wouldn't want
your habitats flipping when they're full of people.</div>
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<div><a
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target="_blank" moz-do-not-send="true">https://www.youtube.com/watch?v=1VPfZ_XzisU</a></div>
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<div>Per that video, you weight it so the axis of rotation
is not the one that's going to cause that sort of
flipping. </div>
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That would mean short, fat cylinders, not long thin ones, no?<br>
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It's interesting that we hadn't really understood this until
relatively recently. Makes me wonder what other physics we are still
completely in the dark about.<br>
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I'm also wondering if a long thin cylinder flipping about a
perpendicular axis would be the disaster we are assuming (everything
inside being thrown about). What forces would the people inside
actually feel? Is it possible they wouldn't even notice unless they
were looking out of the window? Maybe it would be a cool quirk of
orbital habitats, and only be awkward for docking and astronomical
observations, rather than disastrous.<br>
<pre class="moz-signature" cols="72">--
Ben Zaiboc</pre>
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