Re: Iron use: 4000BC

On Fri, 24 Aug 2007 09:13:59 -0500, "Noelie S. Alito"
<noelie@xxxxxxxxxxxx> wrote in <776dnR_WaoE6elPbRVn_vw@xxxxxxxxxxxx> :

Klaus Hellnick wrote:
Augray wrote:
On Tue, 21 Aug 2007 22:41:46 GMT, Klaus Hellnick
<kShePllnAickM@xxxxxxxxxxxxx> wrote in
<KSJyi.47224$Um6.18732@xxxxxxxxxxxxxxxxxxxxxxxxxx> :

Augray wrote:
On 21 Aug 2007 08:17:22 -0700, TomS <TomS_member@xxxxxxxxxxx> wrote in
<197709442.000160ab.003.0001@xxxxxxxxxxxxxxx> :

"On Tue, 21 Aug 2007 10:07:31 -0500, in article
<slrnfclvtj.1qpc.wettering@xxxxxxxxxxxxxxxxxxxxxxx>, Mark
VandeWettering
stated..."
[...snip...]
Iron use does go back to 4000B.C. It was largely because of
meteroric
iron. The ability to smelt iron from ore only happened much
later. We know this because the _furnaces_ themselves _don't_
rust and _aren't_
recycled. These furnaces are rather specialized because of the
high temperatures required. We see no evidence of them anywhere
near 4000 B.C.
[...snip...]

Which makes me wonder how people ever came up with the
idea of smelting iron. Why ever think of making higher
temperature furnaces?
Possibly because meteorites are hot when they first fall from the sky,
and if current furnaces can't re-melt the meteorite, a hotter one may
be required. But admittedly, this is sheer speculation.

Really? They are hot? I find that hard to believe.

That's why you can see them in the sky.


Um, no. A small amount of the surface ablates upon entry for a few
seconds, then the meteor hits terminal velocity and the surface is
cooled by wind. The meteorite may heat slightly upon impact with the
ground, but is unlikely to get hot, especially considering that it
started out extremely cold in space.

Phil Plait addresses this in his book Bad_Astronomy, and online at:

http://www.space.com/scienceastronomy/top5_myths_020903-5.html

Very interesting.

.

Relevant Pages

  • Re: Iron use: 4000BC
    ... The ability to smelt iron from ore only happened much later. ... These furnaces are rather specialized because of the high temperatures required. ... A small amount of the surface ablates upon entry for a few seconds, then the meteor hits terminal velocity and the surface is cooled by wind. ... The meteorite may heat slightly upon impact with the ground, but is unlikely to get hot, especially considering that it started out extremely cold in space. ...
    (talk.origins)
  • Re: Iron use: 4000BC
    ... The ability to smelt iron from ore only happened much later. ... These furnaces are rather specialized because of the high temperatures required. ... A small amount of the surface ablates upon entry for a few seconds, then the meteor hits terminal velocity and the surface is cooled by wind. ... The meteorite may heat slightly upon impact with the ground, but is unlikely to get hot, especially considering that it started out extremely cold in space. ...
    (talk.origins)
  • Re: Iron use: 4000BC
    ... The ability to smelt iron from ore only happened much later. ... These furnaces are rather specialized because of the high temperatures required. ... A small amount of the surface ablates upon entry for a few seconds, then the meteor hits terminal velocity and the surface is cooled by wind. ... The meteorite may heat slightly upon impact with the ground, but is unlikely to get hot, especially considering that it started out extremely cold in space. ...
    (talk.origins)
  • Re: Iron use: 4000BC
    ... The ability to smelt iron from ore only happened much later. ... These furnaces are rather specialized because of the high ... idea of smelting iron. ...
    (talk.origins)
  • Re: Elemental abundances on Earth
    ... >> Only a tiny amount of metallic iron comes from meteorites. ... Range in the US and the Western Australian deposits are meteoritic, ... "Hematite is iron oxide. ... iron from rare meteorite falls. ...
    (sci.astro)