Revision as of 16:54, 11 September 2017 edit AnomieBOT (talk \| contribs) Bots 6,511,102 edits m Substing templates: {{Unsigned}}. See User:AnomieBOT/docs/TemplateSubster for info. ← Previous edit		Revision as of 19:22, 11 September 2017 edit undo Lomn (talk \| contribs) Extended confirmed users 7,070 edits →Black holes: Nothing at all. Next edit →
Line 101: What threat does the earth face from black holes? Could there be some lurking out there that could quite rapidly appear? Maybe small-ish ones, perhaps the size of the moon that we can't / havent detected? <!-- Template:Unsigned IP --><small class="autosigned">— Preceding [[Wikipedia:Signatures\|unsigned]] comment added by [[Special:Contributions/80.195.5.225\|80.195.5.225]] ([[User talk:80.195.5.225#top\|talk]]) 22:33, 10 September 2017 (UTC)</small> <!--Autosigned by SineBot--> :The article [[Primordial black hole]] includes some information indirectly relevant to your questions. Be careful when you discuss "size": do you mean physical dimensions or mass? a black hole the mass of our Moon would, for example, have a 'diameter' of around one tenth of a millimeter (per our [[Black hole]] article): black holes smaller than this should evaporate via [[Hawking radiation]] rather than grow larger by accretion of mass. {The poster formerly known as 87.81.230.195} [[Special:Contributions/2.122.61.201\|2.122.61.201]] ([[User talk:2.122.61.201\|talk]]) 02:52, 11 September 2017 (UTC) :None. None whatsoever. In terms of dangers to the Earth from astronomical bodies, everything is a [[point mass]], and there's nothing remotely special about black holes versus any other wandering mass we might stumble across. A stellar-mass black hole transiting the solar system will probably kill us all by disrupting planetary orbits, because ''any'' stellar mass transiting the solar system will probably kill us all by disrupting planetary orbits. A stellar-mass black hole five light years away will have zero effect on the Earth, because [[alpha centauri\|stellar masses five light years away]] have zero effect on the Earth. Switch things to a black hole with an active [[accretion disk]] throwing hard radiation around and the answer might be different — but we know where those are because they're radiating loudly; they're not (figuratively) "black". — [[User talk:Lomn\|Lomn]] 19:22, 11 September 2017 (UTC) == Island cemeteries ==

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