
Joachim Roenneberg, who foiled Nazi nuclear plan, has died - classicsnoot
http://www.reuters.com/article/us-norway-roenneberg/man-who-foiled-nazi-nuclear-plan-dies-aged-99-idUSKCN1MV0R1
======
pistachiopro
Loosely related, here's a transcript of the reactions of 10 prominent German
nuclear physicists upon hearing the U.S. forces dropped the first atomic bomb:
[http://germanhistorydocs.ghi-
dc.org/pdf/eng/English101.pdf](http://germanhistorydocs.ghi-
dc.org/pdf/eng/English101.pdf)

The scientists, including Heisenberg, Wirtz, and Hahn, had apparently been
captured and detained in a bugged house in England, in an attempt to learn
more about German nuclear capabilities. It's fascinating to see the varying
responses amongst the scientists, from relief that they weren't the ones to
actually implement the bomb, to a seeming sense of frustration to having
"lost" to the American scientists in figuring out how to do it.

~~~
verelo
"WIRTZ: It seems to me that the political situation for STALIN has changed
completely now.

WEIZSÄCKER: I hope so. STALIN certainly has not got it yet. If the Americans
and the British were good Imperialists they would attack STALIN with the thing
tomorrow, but they won't do that, they will use it as a political weapon. Of
course that is good, but the result will be a peace which will last until the
Russians have it, and then there is bound to be war"

That is a pretty great summary of the potential dangers of the Cold War, also
interesting in the context of the US pulling out of the nuclear arms deal with
Russia today.

------
rurounijones
Ray Mears did a fantastic documentary on this subject called the "Real Heroes
of Telemark" \-
[https://www.imdb.com/title/tt0499247/](https://www.imdb.com/title/tt0499247/)
which _really_ shows how hard it was to just survive in that landscape.

Highly recommended viewing (I believe you can find it on youtube).

~~~
celticninja
I remember watching the movie as a kid and being enthralled by the tale.

~~~
flurdy
That was "The Heroes of Telemark"
[https://www.imdb.com/title/tt0059263/](https://www.imdb.com/title/tt0059263/)
from 1965 staring Kirk Douglas.

Ray Mears documentary from 2003 on the real heroes is excellent. I love Ray
Mears.

A few years a big budget TV series was also released "The Saboteurs"
[https://www.imdb.com/title/tt3280150/](https://www.imdb.com/title/tt3280150/)
It is very good.

------
woodandsteel
The German nuclear weapon program had a number of fundamental flaws, according
the Wikipedia article on it, and so I assume it would have failed to produce a
weapon even if Roennenberg's raid had not taken place. However, at the time no
one on the Allied side knew this, and so it made sense to launch the raid.

------
classicsnoot
The operation to blow up the heavy water plant, as well as a lot of
Roennberg's other work, is covered in The Allies Strike Back, 1941-1943 by
James Holland.

------
Thlom
By the end of the war Rønneberg and a small team camped out in a tiny cabin in
the mountains hiding from the Germans and planning sabotage missions agains
German supply lines. The cabin was rebuilt by Rønneberg in the early 1990s and
given to the Hiking association which still maintains it. For a small fee you
can spend the night, highly recommended.

Pictures: [https://www.ut.no/hytte/3.1381/](https://www.ut.no/hytte/3.1381/)

------
PhasmaFelis
Amused that the article calls heavy water "a hydrogen-rich substance". As far
as I'm aware it has exactly the same amount of hydrogen as regular water, by
definition.

Presumably the author was going for "neutron-rich" but misremembered.

~~~
DuskStar
It does have more hydrogen (by weight) than regular water, just not by moles.

~~~
flashman
Correct. A greater fraction of its weight is hydrogen due to the extra
neutron, but it contains the same number of hydrogen atoms.

Heavy water masses 20g/mol versus 18g/mol for regular water.

------
linuxguru
The importance of Heavy Water for the Nazi weapons-development program is
overstated. They could simply have used graphite (carbon) as a moderator, as
the early Manhattan project breeder reactors did. However, they had made a
measurement error on the neutron-absorption cross-section of Carbon, showing
it as too high for use as an efficient moderator, hence they went on a wild-
goose chase to separate Heavy Water by electrolysis, for use as a moderator
using the Norsk Hydro plants at Norway, which were eventually destroyed by
Allied sabotage and bombing. All this rigmarole was therefore due to a small
laboratory-methods error by some little-known German scientist (probably
contamination of his carbon samples with a trace element like Boron or
Cadmium). Graphite was readily available in Axis territory - a few more tests
would likely have found a purer source without Boron contamination.

~~~
Nasrudith
Of course Nazi Germany didn't know that. Destroying their wild goose chase is
ironically still helpful in getting them to divert more resources replacing
it.

------
whatshisface
The Nazis could never have sustained the industrial efforts required to
produce a nuclear weapon. Heavy water is (in comparison) easy to isolate, and
can be bought and sold freely in the west today.

[0]
[http://unitednuclear.com/index.php?main_page=product_info&pr...](http://unitednuclear.com/index.php?main_page=product_info&products_id=135)
[1] [https://www.isowater.com/purchase/](https://www.isowater.com/purchase/)
[2]
[https://www.sigmaaldrich.com/catalog/product/aldrich/151882?...](https://www.sigmaaldrich.com/catalog/product/aldrich/151882?lang=en&region=US)

~~~
ionised
Isn't that why they occupied Norway though, for heavy water?

~~~
qubex
No. The Germans occupied Norway because most of their iron ore supplies (vital
in wartime) came from deposits in northern Norway and because the long
coastline was ideal for placing U-boot bases to harass shipping bringing in
goods to the UK on a northern route. In some sense it was a “preventive
occupation” because Britain and France were obviously eyeing some kind of
interdiction.

