MegaSack DRAW - This year's winner is user - rgwb
We will be in touch
the surface of the planet is largely covered by water - i.e. - a great big heat sink...
radioactivity innit?
pressure plus the earths crust is a good few kilometres thick which separates the water from the hot stuff
a great big heat sink...
You mean a great big saucepan, which is slowly heating up .....it'll be starting to bubble soon 😐
oh, and pressure to!
oh, and pressure to!
it's not heated by the pressure! But I'm sure the core could boil off the thin smear of water on the surface with no significant cooling were it not for the insulating crust!
LOL @ ernie - best throw some sprouts in anytime now then if they're to be ready for christmas!
You say it's hot but Doug Maclure only had a sheen of perspiration in Journey to the Centre of the Earth.
I think it's cosy down there but not [i]that[/i] hot.
but, seriously though - question came from a mate yesterday - more volcano news on the radio had him pondering why, 'when the earth is so old...' has the core not cooled?
Fully agree the crust etc is insulating - yet, still l was left pondering the 'How' of the core keeping hot...
pressure, radioactivity - God leaving the oven on when he made the earth - who knows....
Could be pressure, rotating core etc we don't know 100% but based on theory.
And as above, we're living on the cooler surface.
Liquid planet basically? 😯
Which is older Mars or Earth (Mars is not active so far as we know ut want to know how old it is estimated to Earth)
off to Google...
bawbag - top link!
love the closing statement - (to paraphrase) the earth may well cool right down (over billions of years) - in which case the planet dies...
worry not though - the sun will likely go out first - in which case, planet dies
What tires for riding out planet failure?
I always thought that there is also an element of the tidal forces caused by the moon and sun also flex the body of the planet as well as the oceans. Obviously any flexing will cause heating. But I think the main reason the seas don't boil is as stated the area of the planet (ie the core) where the heat is generated is a long way from, and insulated by the crust. Again as stated if not for that I too think there would be no liquid water on the planet. I have read somewhere that parts of the core are possibly at sun type temperatures. And yes I do know that the sun has different layers with different temperatures but generally sun temps are high enough and with enough energy to boil the oceans many times over.
Mars and Earth would be roughly the same age, having grown from the same dust cloud. Mars got the short end of the stick regarding heavy metals and isotopes, and is sadly dead as a result, despite having had a lot of surface water at one time. If Venus could be shunted out to occupy our orbit in a Legrange point, perhaps it could be cooled and terraformed, but I don't know if it has a molten core or not.
The core heat is maintained by Ro's quite understandable anger at the colour blue
It's like a Pop Tart. Once heated up, it will take billions and billions of years to cool down...
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Maybe it was created that way 🙂
Biscuit, anyone?
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Maybe it was created that way
yeah, it could be [b]Hell[/b] down there...
How do they know it's a big ball of molten metal anyway? (always wondered this)
Seismography.
Seismography.
How'd you mean then?
So Mars was formed 4.6 mill yrs ago estimate.
Wonder why it fazed out its core early compared to Earth.
Wonder what singletrack on Mars would be like!
When did God do all this? 😆
"Wonder what singletrack on Mars would be like!"
FS, hardtail or singlespeed?
Turbo train in Space...
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So glad this thread's come up...been genuinely worried about the planet cooling down + ending up like Mars ever since that blooming Brian Cox documentary.... 😉
bill bryson's book is very good:
'a short history of nearly everything'
- answers lots of questions like this, written in words that thickies like me can understand.
but, basically, it's radioactive decay of nuclear stuff. the same thing that happens in nuclear power stations.
Seismology I should've said. You make a noise on one side of the earth, then listen to see where it comes out on the other side and how long it takes. Cos of the different densities of the things inside the earth the sound waves diffract different amounts, and they can work back from that to get the densities. And hence work out what's in there.
Not entirely convinced that it is radioactive decay. In order for nuclear reactors to get hot you need incredibly un-naturally pure Uranium 235. The earth is mostly iron and silicon and whatnot. Plus most things radioactive have half lives much shorter than the age of the earth. This would mean that one's there now would be a tiny fraction of what was originally there.. meaning that way back when life was evolving the earth would have been like the inside of Chernobyl.
Ooh it's exciting!
Sometimes, when I think about stuff, my mind gets carried away, and it ends up boggled.
I have to have a little lie down then.
molgrips: rocks like granite are radioactive - the heat output is tiny, but it's there, and measurable. add it all up from something the size of the earth, and you've got a lot of energy.
it doesn't matter if you're convinced, the earth doesn't care.
power stations need very pure fuels because we want something that's very hot AND very small. but it's the same fission process at the root of it.
(on top of the heat energy that's still left over from the formation of the planet - where's brian cox when you need him...)
it doesn't matter if you're convinced, the earth doesn't care.
I don't care if you think the earth cares if I'm convinced or not 🙂 You'll forgive me for not instantly believing some reported snippet of information on an internet forum without wanting to do some more research!
The earth is indeed very big which would mean it'd need an awful lot of radioactivity to keep it warm, even more than a reactor.
EDIT: My thought was that it was leftover heat from formation being insulated by the crust, and maybe some kind of frictional effect - backed up by this article
http://www.scientificamerican.com/article.cfm?id=000B2C71-BCF0-1C71-9EB7809EC588F2D7
The earth is spinning and has a gravitational field.
At regular intervals each day a quadrillion civil servants and quangoists sit down and stir their tea in the opposite direction to the earth's rotation. This cause resistance in the earth's gravitational field and hence heat.
It is believed that a rapid response squad of civil servants took several more tea breaks over the last year to increase this effect and create more volcanic eruptions. This was to punish Iceland for stealing almost as much money from us as American bankers.
Hope this helps.
What tyres for mars ?
molgrips - Member
You'll forgive me for not instantly believing some reported snippet of information on an internet forum without wanting to do some more research!
you sir, are a true scientist, and an example for us all.
homework is fun!
How come the earths core remains mad hot and molten
TJ lives there and the heat is created by the fury of his indignation.