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Weird. Why would anybody expect Earth to collapse at all, or to wait billions of years to collapse, or to collapse, but Jupiter not collapse first? Or not wonde
by ncmncm 5y ago
Weird. Why would anybody expect Earth to collapse at all, or to wait billions of years to collapse, or to collapse, but Jupiter not collapse first? Or not wonder why their own head doesn't?
- chaps 5y agoWhy wouldn't they expect it? It's a perfectly valid question to tease out curious aspects from our reality.
- erwincoumans 5y agoWhy? Because * people need to be educated, and this article does a good job * different forces dominate at different sizes For a skull, gravitational forces of a human head are tiny. Collapse is prevented because of skull rigid structure that supports itself: inward forces are resisted by resistance to deformation and pressure (similar to semi-spherical cellars and rounded bridges) Earth has large gravitational forces, but resistance to compresson of its solid inner core and liquid iron outer core prevents collapse. Stars are much bigger, and the larger gravitational forces are resisted by an additional force, next to resistance of compression gasses: Nuclear reactions produce radiation in the form of photons that are streaming out from the star's interior creating outward pressure forces.
- codeflo 5y agoTo simplify even more, both the Earth and your head would eventually collapse due to gravity if it weren't for electromagnetic forces pushing the atoms apart. I would be in free fall towards the Earth's center right now if it weren't for the atoms in my couch pushing the atoms in my butt upwards.
- ncmncm 5y agoAll I can say is better them than me.
- mannykannot 5y agoWhy ask 'why' at all, about anything? In particular, why did you ask this question? There is a plausible Darwinian story to be told about why generalized curiosity about causes abets fitness, but no-one would have come up with that explanation without asking quite a few questions about why things are as they are.
- dcow 5y ago> There is a plausible Darwinian story to be told about why generalized curiosity about causes abets fitness… HN has served it’s purpose this morning I can now go about my day (first order, of course: feed the cats). Bravo.
- jrootabega 5y agoIt's a kids'/popular science q&a site. I don't think it lines up well with the audience here, but it's a fine question for that site.
- SiempreViernes 5y agoYeah, the question might stem from someone overemphasising that stars don't live forever which lead to the generalisation that everything in astronomy collapses.
- croes 5y agoMatter is mostly empty space, so enough for a collapse.
- willis936 5y agoThe Earth is the most dense celestial body in the solar system that weighs more than 10^20 kg.