---- START NEW MESSAGE --- Received: from cherry.ease.lsoft.com [209.119.0.109] by dpmail10.doteasy.com with ESMTP (SMTPD32-8.05) id A3221F2400FA; Wed, 28 Jan 2004 06:11:46 -0800 Received: from PEAR.EASE.LSOFT.COM (209.119.0.19) by cherry.ease.lsoft.com (LSMTP for Digital Unix v1.1b) with SMTP id <4.00CC0E16@cherry.ease.lsoft.com>; Wed, 28 Jan 2004 9:11:39 -0500 Received: from MITVMA.MIT.EDU by MITVMA.MIT.EDU (LISTSERV-TCP/IP release 1.8e) with spool id 9610 for PICLIST@MITVMA.MIT.EDU; Wed, 28 Jan 2004 09:11:31 -0500 Received: from MITVMA (NJE origin SMTP@MITVMA) by MITVMA.MIT.EDU (LMail V1.2d/1.8d) with BSMTP id 1996; Wed, 28 Jan 2004 09:09:30 -0500 Received: from smtp-out3.xs4all.nl [194.109.24.13] by mitvma.mit.edu (IBM VM SMTP Level 430) via TCP with ESMTP ; Wed, 28 Jan 2004 09:09:29 EST X-Comment: mitvma.mit.edu: Mail was sent by smtp-out3.xs4all.nl Received: from PAARD (a213-84-20-53.adsl.xs4all.nl [213.84.20.53]) by smtp-out3.xs4all.nl (8.12.10/8.12.10) with ESMTP id i0SE9U0a064270 for ; Wed, 28 Jan 2004 15:09:31 +0100 (CET) MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook, Build 10.0.3416 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2600.0000 Importance: Normal Message-ID: <001601c3e5a8$59e67dd0$0b00a8c0@PAARD> Date: Wed, 28 Jan 2004 15:09:30 +0100 Reply-To: pic microcontroller discussion list Sender: pic microcontroller discussion list From: Wouter van Ooijen Organization: Van Ooijen Technische Informatica Subject: Re: [OT]: JAL licensing (was SCO lobbying Congress about Linux) To: PICLIST@MITVMA.MIT.EDU In-Reply-To: <20040128135844.GB24714@ixion.tartarus.org> Precedence: list X-RCPT-TO: Status: U X-UIDL: 371856105 > Do you want to ensure that any enhanced version of the > library can still > be used in closed-source commercial firmware? Yes. And on top of that I want to be sure that when such a library is spread it is still free in the same sense as my original. Wouter van Ooijen -- ------------------------------------------- Van Ooijen Technische Informatica: www.voti.nl consultancy, development, PICmicro products -- http://www.piclist.com hint: The list server can filter out subtopics (like ads or off topics) for you. See http://www.piclist.com/#topics . Return-Path: <> Received: from mitvma.mit.edu ([18.92.0.3]) by tomts12-srv.bellnexxia.net (InterMail vM.5.01.06.05 201-253-122-130-105-20030824) with ESMTP id <20040128001154.MYKS5780.tomts12-srv.bellnexxia.net@mitvma.mit.edu> for ; Tue, 27 Jan 2004 19:11:54 -0500 Received: by mitvma.mit.edu (IBM VM SMTP Level 430) via spool with SMTP id 6074 ; Tue, 27 Jan 2004 19:11:50 EST Received: from MITVMA.MIT.EDU (NJE origin LISTSERV@MITVMA) by MITVMA.MIT.EDU (LMail V1.2d/1.8d) with BSMTP id 1027; Tue, 27 Jan 2004 19:11:51 -0500 Date: Tue, 27 Jan 2004 19:11:51 -0500 From: "L-Soft list server at MITVMA.MIT.EDU (1.8e)" Subject: PICLIST: error report from YAHOO.COM To: listsjosh@3MTMP.COM, piclist_errors@SYMPATICO.CA Message-ID: X-LSV-ListID: None The enclosed message has been identified as a delivery error for the PICLIST list because it was sent to 'owner-piclist@MITVMA.MIT.EDU'. ------------------------------ Message in error ------------------------------- Received: from MITVMA (NJE origin SMTP@MITVMA) by MITVMA.MIT.EDU (LMail V1.2d/1.8d) with BSMTP id 0999; Tue, 27 Jan 2004 19:10:58 -0500 Received: from *unknown [66.218.86.169] by mitvma.mit.edu (IBM VM SMTP Level 430) via TCP with SMTP ; Tue, 27 Jan 2004 19:10:57 EST X-Warning: mitvma.mit.edu: Could not confirm that host [66.218.86.169] is mta252.mail.scd.yahoo.com From: MAILER-DAEMON@yahoo.com To: owner-piclist@mitvma.mit.edu X-Loop: MAILER-DAEMON@yahoo.com Subject: Delivery failure Message from yahoo.com. Unable to deliver message to the following address(es). : Sorry, your message to hbarregrd@yahoo.com cannot be delivered. This account is over quota. --- Original message follows. The original message is over 5K. Message truncated. Return-Path: Received: from 209.119.0.109 (EHLO cherry.ease.lsoft.com) (209.119.0.109) by mta252.mail.scd.yahoo.com with SMTP; Tue, 27 Jan 2004 13:41:12 -0800 Received: from PEAR.EASE.LSOFT.COM (209.119.0.19) by cherry.ease.lsoft.com (LSMTP for Digital Unix v1.1b) with SMTP id <10.00CBF77D@cherry.ease.lsoft.com>; Tue, 27 Jan 2004 13:16:39 -0500 Received: from MITVMA.MIT.EDU by MITVMA.MIT.EDU (LISTSERV-TCP/IP release 1.8e) with spool id 0027 for PICLIST@MITVMA.MIT.EDU; Tue, 27 Jan 2004 13:16:19 -0500 Received: from MITVMA (NJE origin SMTP@MITVMA) by MITVMA.MIT.EDU (LMail V1.2d/1.8d) with BSMTP id 0551; Tue, 27 Jan 2004 13:15:56 -0500 Received: from pd2mo2so.prod.shaw.ca [24.71.223.10] by mitvma.mit.edu (IBM VM SMTP Level 430) via TCP with ESMTP ; Tue, 27 Jan 2004 13:15:56 EST X-Comment: mitvma.mit.edu: Mail was sent by pd2mo2so.prod.shaw.ca Received: from pd2mr2so.prod.shaw.ca (pd2mr2so-ser.prod.shaw.ca [10.0.141.109]) by l-daemon (iPlanet Messaging Server 5.2 HotFix 1.18 (built Jul 28 2003)) with ESMTP id <0HS50080TTBLJB@l-daemon> for PICLIST@MITVMA.MIT.EDU; Tue, 27 Jan 2004 10:45:21 -0700 (MST) Received: from pn2ml10so.prod.shaw.ca (pn2ml10so-qfe0.prod.shaw.ca [10.0.121.80]) by l-daemon (iPlanet Messaging Server 5.2 HotFix 1.18 (built Jul 28 2003)) with ESMTP id <0HS5009R7TBLLS@l-daemon> for PICLIST@MITVMA.MIT.EDU; Tue, 27 Jan 2004 10:45:21 -0700 (MST) Received: from UALBERTA.ca (h24-65-14-55.ed.shawcable.net [24.65.14.55]) by l-daemon (iPlanet Messaging Server 5.2 HotFix 1.18 (built Jul 28 2003)) with ESMTP id <0HS500L05TBLY0@l-daemon> for PICLIST@MITVMA.MIT.EDU; Tue, 27 Jan 2004 10:45:21 -0700 (MST) MIME-version: 1.0 X-Mailer: Mozilla 4.76 [en] (Win98; U) Content-type: text/plain; charset=iso-8859-1 Content-transfer-encoding: QUOTED-PRINTABLE X-Accept-Language: en References: <0f1901c3e4ba$3c7caec0$e7bdf682@space.rl.ac.uk> <01c901c3e4bd$47195420$7b01a8c0@Paradise> Message-ID: <4016A3C2.6445C893@UALBERTA.ca> Date: Tue, 27 Jan 2004 10:45:38 -0700 Reply-To: pic microcontroller discussion list Sender: pic microcontroller discussion list From: Robert Rolf Organization: U of Alberta Subject: Re: [OT]: Beagle2 Hohmann To: PICLIST@MITVMA.MIT.EDU Precedence: list Russell McMahon wrote: >=20 > > >Incidentally, why are there so many Mars missions arriving there > > >all at once? Is there some astronomical-geometry that favours i= t? > > > > Probably because mars has been the closest to earth for some 28,0= 00 years, > > so the travel time is shortest, and there is probably an advantag= e in > signal > > strengths as well. >=20 > The minimum energy path between two bodies in Keplerian circular or= bits is > named a Hohman transfer. It is an ellipse which is tangential to bo= th orbits > where it touches the source and target. This alignment with earth a= nd mars > occurs variably. The present closest approach for yonks condition p= robably > makes it especially attractive. >=20 > Good explanation of Hohman transfer here (note the server ! :-) ) >=20 > http://web.mit.edu/12.000/www/teams/9/trajectory/hohman.htm= l >=20 > Named afaik for a NASA scientist who first thought of it. Not quite. There was no NASA in 1925 if this Stanford quiz is to be believed. However, there does appear to have been a Hofman at NASA, hence the c= onfusion with Hohmann. http://quizbowl.stanford.edu/archive/spencer01/SS2.htm 9. Using the vis-viva equation, one can easily find the delta-v=20 needed to enter one; let the second term be the arithmetic mean=20 of the lower and higher orbits' radii. They require only two delta-v'= s, as at both endpoints they are tangent to the initial and final orbits. F= TP,=20 name these elliptical paths,=20 first worked out by their namesake discoverer in 1925,=20 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the most fuel-efficient transfer orbit between one circular path and another. ANSWER: Hohmann transfer orbit http://www.astro.amu.edu.pl/~breiter/lectures/astrody/Hohmann.pdf Walter Hohmann (1880=961945) was a professional engineer who eventually became the city architect of Essen, Germany. In 1925 he published his masterpiece, Die Erreichbarkeit der Himmelsk=F6rper (The Attainability of Celestial Bodies), in which he demonstrated that the interplanetary trajectory requiring the least expenditure of energy is an ellipse tangent to the orbits of both the departure and the arrival planets. The =93Hohmann transfer ellipse=94 has endured, but his investigations in interplanetary mission design go far beyond that result and represent a milestone in the development of space travel. etc. Robert -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: *** MESSAGE TRUNCATED *** .. .