X-GM-THRID: 1212409830910288796 X-Gmail-Labels: rsgb lf X-Gmail-Received: d0ecd620b978b52050d16b8712a57745c5f418f8 Delivered-To: daveyxm@gmail.com Received: by 10.64.249.16 with SMTP id w16cs284545qbh; Wed, 23 Aug 2006 02:21:35 -0700 (PDT) Received: by 10.48.210.16 with SMTP id i16mr1634064nfg; Wed, 23 Aug 2006 02:21:35 -0700 (PDT) Return-Path: Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by mx.gmail.com with ESMTP id r34si2078492nfc.2006.08.23.02.21.32; Wed, 23 Aug 2006 02:21:35 -0700 (PDT) Received-SPF: neutral (gmail.com: 193.82.116.20 is neither permitted nor denied by best guess record for domain of owner-rsgb_lf_group@blacksheep.org) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1GFopQ-00017p-CN for rs_out_1@blacksheep.org; Wed, 23 Aug 2006 10:15:16 +0100 Received: from [193.82.116.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1GFopP-00017g-Sv for rsgb_lf_group@blacksheep.org; Wed, 23 Aug 2006 10:15:15 +0100 Received: from relay.dera.gov.uk ([192.5.29.49] helo=relay.dstl.gov.uk) by relay1.thorcom.net with smtp (Exim 4.62) (envelope-from ) id 1GFopM-00032u-1M for rsgb_lf_group@blacksheep.org; Wed, 23 Aug 2006 10:15:15 +0100 Received: (qmail 5857 invoked from network); 23 Aug 2006 10:14:31 +0100 Received: from warlock.dstl.gov.uk (192.5.29.10) by relay.dera.gov.uk with SMTP; 23 Aug 2006 10:14:31 +0100 Message-ID: <7D653C9C42F5D411A27C00508BF8803D06BF2D35@mail.dstl.gov.uk> From: Talbot Andrew To: rsgb_lf_group@blacksheep.org Date: Wed, 23 Aug 2006 10:14:35 +0100 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2653.19) X-Spam-Score: 0.6 (/) X-Spam-Report: autolearn=disabled,AWL=0.458,FORGED_RCVD_HELO=0.05,HTML_40_50=0.086,HTML_MESSAGE=0.001 Subject: RE: LF: Re: Alarming message Content-Type: multipart/alternative; boundary="----_=_NextPart_001_01C6C694.8D701952" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.6 required=5.0 tests=HTML_20_30,HTML_FONTCOLOR_BLUE, HTML_MESSAGE autolearn=no version=2.63 X-SA-Exim-Scanned: Yes Sender: owner-rsgb_lf_group@blacksheep.org Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group X-SA-Exim-Rcpt-To: rs_out_1@blacksheep.org X-SA-Exim-Scanned: No; SAEximRunCond expanded to false Status: O X-Status: X-Keywords: X-UID: 4459 This message is in MIME format. Since your mail reader does not understand this format, some or all of this message may not be legible. ------_=_NextPart_001_01C6C694.8D701952 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable My understanding of EMP Nuclear bombs - gained from documentation from th= e 1960s/70s, was that these were exo-atmospheric bursts designed to generat= e huge impulses at the ground due to Compton scattering of electrons blaste= d down from the upper atmosphere. =20 Tests ( on BikiniAtol ?) caused severe disruption to electronic equipmen= t hundreds to thousands of km away, and are even reputed to have knocked ou= t streetlights at those sorts of distances. =20 I don't see how satellites well above the atmosphere could be disrupted b= y such an event. Direct satelite damage was very difficult to produce then= due to the difficulties of getting close enough - even a 1MT bomb probabl= y has to be within less than a kilometre of a satellite for its direct radiation to be high enough to damage the electronics (no blast damage in= space !) Satellites are designed to withstand high radiation levels from= the sun. Rember the huge programme of Star Wars started in the '80's. Nowadays such close positioning would be easier, of course. =20 So it looks as if satcoms would survive, whereas HF and ground based electronics would not. SRI, fellow amateurs hoping for a return to HF! =20 All info gained from open literature ;-) =20 Andy G4JNT =20 =20 _____ =20 From: owner-rsgb_lf_group@blacksheep.org [mailto:owner-rsgb_lf_group@blacksheep.org] On Behalf Of Andre Kesteloot Sent: 22 August 2006 16:14 To: rsgb_lf_group@blacksheep.org Subject: Re: LF: Re: Alarming message Hugh_m0wye wrote:=20 3. The supposed disruption to satelites caused by a HANE seems to be base= d on what happened to Telstar and similar vintage space-craft. Surely satel= ite design has progressed since then, with better shielding and "radiation hardened" devices being used. If satelites are more robust then much of t= he reason for using RBR evaporates. It could be that the concerns may be over the possibility of a North Kore= an missile sent in space to create an EMP and wiping out satellite communications There is a difference between space equipment being "radiation-hardened" against the radiations normally found in space, and the neutrons. etc, th= at could be created by a nuclear device exploded in space. 73 Andr=E9 N4ICK "This e-mail is intended for the recipient only. If you are not the intended recipient you must not use, disclose, distribute, copy, print, or rely upon this e-mail. If an addressing or transmission error has misdirected this e-mail, please notify the author by replying to this e-m= ail." "Recipients should note that all e-mail traffic on MOD systems is subject to monitoring and auditing." ------_=_NextPart_001_01C6C694.8D701952 Content-Type: text/html; charset="iso-8859-1"
My understanding of EMP Nuclear bombs - gained from documentation from the 1960s/70s, was that these were exo-atmospheric bursts designed to generate huge impulses at the ground due to Compton scattering of electrons blasted down from the upper atmosphere.
 
Tests  ( on BikiniAtol ?) caused severe disruption to electronic equipment hundreds to thousands of km away, and are even reputed to have knocked out streetlights at those sorts of distances.
 
I don't see how satellites well above the atmosphere could be disrupted by such an event.  Direct satelite damage was very difficult to produce then due to the difficulties of getting close enough - even a 1MT bomb probably has to be within less than a kilometre of a satellite for its direct radiation to be high enough to damage the electronics (no blast damage in space !)  Satellites are designed to withstand high radiation levels from the sun.   Rember the huge programme of Star Wars started in the '80's.  Nowadays such close positioning would be easier, of course.
 
So it looks as if satcoms would survive, whereas HF and ground based electronics would not.   SRI, fellow amateurs hoping for a return to HF!
 
All info gained from open literature ;-)
 
Andy  G4JNT

 


From: owner-rsgb_lf_group@blacksheep.org [mailto:owner-rsgb_lf_group@blacksheep.org] On Behalf Of Andre Kesteloot
Sent: 22 August 2006 16:14
To: rsgb_lf_group@blacksheep.org
Subject: Re: LF: Re: Alarming message

Hugh_m0wye wrote:


3. The supposed disruption to satelites caused by a HANE seems to be based on what happened to Telstar and similar vintage space-craft. Surely satelite design has progressed since then, with better shielding and "radiation hardened" devices being used. If satelites are more robust then much of the reason for using RBR evaporates.

It could be that the concerns may be over the possibility of a North Korean missile sent in space to create an EMP and wiping out satellite communications
There is a difference between space equipment being "radiation-hardened" against the radiations normally found in space, and the neutrons. etc, that could be created by a nuclear device exploded in space.

73
Andr�  N4ICK
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"For those other than the recipient any disclosure, copying, distribution, "
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