From owner-freebsd-hardware Thu Dec 30 9: 0:57 1999 Delivered-To: freebsd-hardware@freebsd.org Received: from lambic.physics.montana.edu (lambic.physics.montana.edu [153.90.192.128]) by hub.freebsd.org (Postfix) with ESMTP id 0E5A614A0A for ; Thu, 30 Dec 1999 09:00:55 -0800 (PST) (envelope-from handy@lambic.physics.montana.edu) Received: from localhost (handy@localhost) by lambic.physics.montana.edu (8.9.3/8.9.3) with ESMTP id KAA19945; Thu, 30 Dec 1999 10:00:37 -0700 (MST) (envelope-from handy@lambic.physics.montana.edu) Date: Thu, 30 Dec 1999 10:00:37 -0700 (MST) From: Brian Handy To: Nate Williams Cc: Nathan Mahon , Poul-Henning Kamp , freebsd-hardware@FreeBSD.ORG Subject: Re: ECC RAM useless with FreeBSD? In-Reply-To: <199912301604.JAA24451@mt.sri.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-hardware@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org >> [Woo hoo! Space stuff!] >> Aren't we talking about laptops for astronauts? they're going to be >> used in zero-gravity right? so what does it matter what they weigh? > >Because until they get into orbit, they have weight which must be >propelled into space. Getting it into space is expensive, and there's >no need for ruggedization (except to keep out radiation) like the >military requires. Yep, weight's an issue. It's a little more relaxed on the shuttle than other launchers, but getting stuff into space runs upwards of US$7,000/lb. I think the shuttle is worse than that. The tradeoffs are pretty obvious; you give up altitude for weight. The other major concerns are surviving the vibration at launch, thermal worries, and safety. Weight's a much much bigger issue on the smaller launch vehicles, where there's a set limit on how much you can launch, and you're constantly trading serious quantities of altitude for weight. (Most of the stuff I do is in this category -- Pegasus XLs for Small Explorer class satellites, and Black Brandts/Nike missiles for sounding rockets.) They launch people will even give you a nice graph of altitude vs. payload weight. To finish my thought, now that I'm sure I'm off on a tangent: I don't know what effect low atmospheric pressure and no gravity would have on cooling in a laptop, but someone would probably want to know. And safety on the shuttle is a HUGE issue -- having a battery blow up in an astronaut's lap would probably be an Issue. :-) Er, what was the question? Brian To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hardware" in the body of the message