Return-path: X-Andrew-Authenticated-as: 7997;andrew.cmu.edu;Ted Anderson Received: from corsica.andrew.cmu.edu via trymail for +dist+/afs/andrew.cmu.edu/usr1/ota/space/space.dl@andrew.cmu.edu (->+dist+/afs/andrew.cmu.edu/usr1/ota/space/space.dl) (->ota+space.digests) ID ; Wed, 6 Sep 89 03:18:40 -0400 (EDT) Message-ID: Reply-To: space+@Andrew.CMU.EDU From: space-request+@Andrew.CMU.EDU To: space+@Andrew.CMU.EDU Date: Wed, 6 Sep 89 03:18:32 -0400 (EDT) Subject: SPACE Digest V10 #24 SPACE Digest Volume 10 : Issue 24 Today's Topics: Re: Printing On a LaserWriter -- hints Re: Voyager Pics Re: Where the hell are electric-ion thrusters???? Re: Electric Rockets Re: Galileo Mission SPACE ACTIVIST ALERT Re: Neptune on the Boobtube Re: Economies of Scale in Launchers Re: Voyager Pics Re: PHONE TREE ALERT ---------------------------------------------------------------------- Date: 30 Aug 89 14:27:38 GMT From: mailrus!csd4.csd.uwm.edu!mrsvr.UUCP!shoreland.uucp!hallett@tut.cis.ohio-state.edu (Jeff Hallett x4-6328) Subject: Re: Printing On a LaserWriter -- hints In article <123914@sun.Eng.Sun.COM> lemay@sun.UUCP (Laura Lemay) writes: > >Although the Mac advertises as WYSIWYG, it is not necessarily so. Fonts >that are displayed on the screen are not the same size/shape etc as the >postscript fonts that appear printed on the LW. So the laserwriter reformats >everything as best it can with the font it is told to use. (All right, The easier way is to get the actual Adobe fonts. The Apple fonts differ slightly in spacing and style than the Adobe ones - enough to make them print differently. If you go over to CompuServe in the Adobe forum, you can get any screen font you want. Some of them are also on Sumex-Aim, through anonymous FTP. > >3. How do I keep a startup page from printing when I turn on the laserwriter? > >This has been beaten to death on this bboard for a while now, but basically >tehre are two ways to do it: > >1. (If you're not a postscript hacker). Pull out the paper tray an inch >or so when the LW starts up, until the orange light goes on steadily. > >2. (If you are a postscript hacker). Damn. I thought I rememebred this >one. Basically it involves getting into interactive mode with the laserwriter >(or sending a script to the LW interactively), and changing a variable >called "setdostartpage." Sigh. Is tehre someone out there who could >write the actual script to be downloaded to the LW and post it? The code is "0 serverdict begin exitserver statusdict begin false setdostartpage end". To make it print again, substitute "true" for "false". Even better is to get the Word document from Sumex-Aim that has this code built into it and send that when you want it off. Best is to get DiskTop from CE Software which includes a number of LaserWriter utilities, including ones to show the current LaserWriter status and toggle the startup page. >On interesting quirk of having fonts in the laserwriter is that these mathematical >formulas for fonts can be scaled to any size. You may only have four sizes >of a particular font installed in you system, but you can print any size you >want on the LW. Depending on the program you use, larger or wierd size fonts >will either not be available or will come out looking really wierd on the screen. >But they will look fine when printed. To paraphrase Chuq VonRospach, "Fixed in System 7.0" (somewhat). Good posting Laura. Someone should set their server to repost this every month. :^) :^) -- Jeffrey A. Hallett, PET Software Engineering GE Medical Systems, W641, PO Box 414 Milwaukee, WI 53201 (414) 548-5163 : EMAIL - hallett@positron.gemed.ge.com ------------------------------ Date: 30 Aug 89 13:33:28 GMT From: tank!eecae!cps3xx!usenet@handies.ucar.edu (Usenet file owner) Subject: Re: Voyager Pics In article adam@mit-amt.MEDIA.MIT.EDU (Adam Glass) writes: >neptute and triton pictures) from their machine. I think it was >grape.ecs.clarkson.edu. Anyway, I ftp's there and went into binary >mode and got a bunch of pics. But when I ftp's them down to the mac I can't ftp from grape.ecs.clarkson.edu because their ftp is incompatible with our ftp. I don't know if theirs is "standard" or not, but I do know I can't change ours. I have no system privileges, and I do not have enough disk space to have my own copy of ftp like others have suggested. I guess I'm complaining. Our ftp works with everybody else's that I've tried. Ken. In the rare case that original ideas Kenneth J. Hendrickson N8DGN are found here, I am responsible. Owen W328, E. Lansing, MI 48825 Internet: hendrick@frith.egr.msu.edu UUCP: ...!frith!hendrick ------------------------------ Date: 29 Aug 89 22:36:17 GMT From: vsi1!daver!lynx!neal@apple.com (Neal Woodall) Subject: Re: Where the hell are electric-ion thrusters???? In article <1989Aug29.153247.4598@utzoo.uucp> henry@utzoo.uucp (Henry Spencer) writes: >In article <6091@lynx.UUCP> neal@lynx.UUCP (Neal Woodall) writes: >>... Why the hell cannot our country do with two fewer >>B2 bombers, and give that money to JPL for probes, including a full >>program of electric-ion engine probes to various parts of the solar system? >Because Congress isn't willing to move funds around like that. If you feel >this is unfair... have you talked to *YOUR* Congressthing about it lately? >If not, why not? It so happens that I am VERY involved in lobbying Congress for issues that I care about.....I havn't written any letters or talked to any staffers of my Congressman lately, but I will very soon, and this will be near the top of the list. >>... Hell, a manned Mars mission would be fast with an ion thruster! >Well, let's not get carried away; the thrust of the things is pretty low. >But yes, it would help. Which is why the Soviets are working on nuclear- >electric propulsion for their Mars mission. Sure, the thrust is low, but the nice thing about electric-ion thrusters is the fact they have much greater delta-v potential because they are much higher specific impulse (I think that recently someone showed they are about an order of magnitude higher than the Saturn F1 or J2 engines in specific impulse) AND the fact that they can run for 1000's of hours continuously. Sure the acceleration is much lower, but think of what happens when you accelerate continuously for 1000's of hours. Instead of drifting most of the way to a target planet, an electric-ion thruster equipped probe could accelerate half-way, then decelerate the other half.....trip time would be greatly decreased for long trips. Neal ------------------------------ Date: 30 Aug 89 14:19:05 GMT From: rochester!dietz@rutgers.edu (Paul Dietz) Subject: Re: Electric Rockets Of course, I meant "expendable", not "expandable". Paul F. Dietz dietz@cs.rochester.edu ------------------------------ Date: 29 Aug 89 22:39:24 GMT From: vsi1!daver!lynx!neal@apple.com (Neal Woodall) Subject: Re: Galileo Mission In article <6103@lynx.UUCP> neal@lynx.UUCP (Neal Woodall) writes: [my thoughts on Christic's efforts to ground Galileo deleted] >I have been reading the Christic stuff in this group for many months now... Of course, I intended to say that I read about them in misc.legal! Neal ------------------------------ Date: 30 Aug 89 15:13:50 GMT From: agate!usenet@ucbvax.Berkeley.EDU (William Baxter) Subject: SPACE ACTIVIST ALERT Call the offices of Robert G. Torricelli (202/225-5061) and Robert Roe (202/225-5751). Ask them as members of the Space Science and Applications Subcommittee to call for hearings on HR2674 as soon as possible. Ask them to cosponsor the bill. If you need a copy of HR2674, the Space Transportation Services Purchase Act of 1989, wend me email. William Baxter ARPA: web@{garnet,brahms,math}.Berkeley.EDU UUCP: {sun,dual,decwrl,decvax,hplabs,...}!ucbvax!garnet!web CALL YOUR CONGRESSMAN AND SCREAM AT HIM UNTIL HE THINKS THAT SPACE ACTIVISM CONSISTS ONLY OF ASKING FOR MORE MONEY FOR NASA ------------------------------ Date: 30 Aug 89 21:15:54 GMT From: cs.utexas.edu!barnett@tut.cis.ohio-state.edu (Lewis Barnett @ home on the range) Subject: Re: Neptune on the Boobtube In article <980@corpane.UUCP> sparks@corpane.UUCP (John Sparks) writes: > >At one point a caller asked what will happen to Voyager, where will it go when >it leaves the system. > >The answer was that in 8,000 years it will fly by Barnard's Star, in 20,000 or >so it will pass Proxima Centauri, and then the Oort cloud. > >GACK!!! How bass-ackwards can you get?!!! > >John Sparks | {rutgers|uunet}!ukma!corpane!sparks | D.I.S.K. 24hrs 1200bps Yep, it sounds pretty dumb (and is), but I think that what really happened was that the guys commenting had abstracted out some vital information in preparing a thumbnail timeline. I saw the figures about closest approaches to celestial objects that I think those comments were based on, and the chronology is actually correct. Problem is, that "closest" approach to Barnard's star takes voyager to "within" 5 or 6 lightyears (don't remember the exact figures) while it's still under a lightyear from us, and I assume, still within the cometary halo. Funny the way things get twisted around, isn't it? Lewis Barnett -- barnett@CS.UTEXAS.EDU, barnett@im4u.UUCP, {pyramid,sequent,harvard,gatech,ctvax,uunet}!cs.utexas.edu!barnett ------------------------------ Date: 29 Aug 89 15:20:16 GMT From: cs.utexas.edu!wasatch!uplherc!esunix!bambam!bpendlet@tut.cis.ohio-state.edu (Bob Pendleton) Subject: Re: Economies of Scale in Launchers From article <310013@hpclove.HP.COM>, by campbelr@hpclove.HP.COM (Bob Campbell): >> Nope, high molecular weigth exhaust is better in a high pressure >> environment. That is why there are solid fuel strap ons on so many >> boosters. In a vacuum you want the lowest possible weight exhaust. >> >> Bob P. > > Are we confusing high thrust with efficiency? Could be. I don't claim to be an expert. I'm basing this on some articles on tripropellant rockets in "Aerospace America" and conversations about those articles with folks I know who build solid rockets for a living. A tripropellant rocket starts out burning LOX and a high molecular hydrocarbon fuel. As it climbs it reduces the percentage of hydrocarbon fuel and increases the percentage of pure LH2 it burns until when it is in a vacuum it is burning LOX and LH2. This approach was being discussed as one way to achieve single stage to orbit capability. A simpler way to get the same effect is to use two stages. The first stage burns LOX/hydrocarbon. The second stage burns LOX/LH2. As I remember it, I don't have the articles with me, The effective back pressure is lower for a high molecular weight exhaust. I could have this wrong. But, "Aerospace America" is the journal of the American Insitute for Aeronautics and Astronautics and they did say that high molecular weight exhaust is preffered in the lower atmosphere. I hate to resort to an agument from authority, but that's the best I can do right now. Bob P. -- Bob Pendleton, speaking only for myself. UUCP Address: decwrl!esunix!bpendlet or utah-cs!esunix!bpendlet Reality is stanger than most people can imagine ------------------------------ Date: 30 Aug 89 07:09:29 GMT From: agate!shelby!portia!hanauma!joe@ucbvax.Berkeley.EDU (Joe Dellinger) Subject: Re: Voyager Pics In article <4358@cps3xx.UUCP> hendrick@frith.UUCP (Hendrickson) writes: >So, does anybody know when these fabulous pics of neptune will be >available in sun workstation format, or in .GIF format? Look over in comp.graphics; some people over there have announced their availability in other formats. (Basically all these "different formats" consist of some magic header, followed by the same old image in bytes. That's why I like to distribute just the bytes and leave the "header" in English. It's the most universal, comprehensible, and elegant format, IMHO.) P.S.: Strangely enough, among the many machines grabbing copies of the images have been several machines at JPL. \ /\ /\ /\/\/\/\/\/\/\.-.-.-.-.......___________ \ / \ / \ /Dept of Geophysics, Stanford University \/\/\.-.-....___ \/ \/ \/Joe Dellinger joe@hanauma.stanford.edu apple!hanauma!joe\/\.-._ ------------------------------ Date: 30 Aug 89 14:57:40 GMT From: agate!usenet@ucbvax.Berkeley.EDU (William Baxter) Subject: Re: PHONE TREE ALERT In article <5176@mtgzx.att.com>, dls@mtgzx (d.l.skran) writes: >I am writing for the benefit of innocent new NSS members who have yet >to discover the complexities of pro-space activism, and who probably think >Baxter holds some high office at NSS Headquarters. The typical NSS member has yet to discover space activism in any form. NSS Phone Tree Alerts protect them from this by calling only for more ritual budget sacrifices to NASA. Who is your congressman, Dale? When were you last at his office? What does he think of HR2674? Will he cosponsor it? >I would further like to state that I personally support this bill, What does this mean? Do you mean you have read it and think it is the right course of action? That you phoned or wrote your representatives about it? That you visited them and asked them to cosponsor? That you talked about it with other space nerds? That you mailed a copy to everyone you thought might be interested? That you even discussed it with people who are not particularly interested in space? >and that as far as I know so do Scot Pace and the NSS Legislative >Committee. The bill has been distributed by NSS Headquarters to chapters >so they can organize support for it. In fact, I know of no one who >actually opposes this bill. This statement indicates that Dale has no clue about what is happening with the bill. Scott Pace and the Legislative Committee say that they support it. They are not doing anything to help pass it. Sending the bill to chapters? That would cost them all of about $150. If that is all that they are willing to do, then they are clearly not interested in making the bill pass. At the Legislative Committee meeting in Chicago there was no discussion about how to get the bill to pass. Instead, they talked about altering it and getting credit for it. (I was there) If you want to see HR2674 pass, convince your congressman to cosponsor it. Convince your senators to support it. Convince your friends to do the same. Engage in space activism. Do you have a copy of HR2674, the Space Transportation Services Purchase Act of 1989? If not, send me email. William Baxter ARPA: web@{garnet,brahms,math}.Berkeley.EDU UUCP: {sun,dual,decwrl,decvax,hplabs,...}!ucbvax!garnet!web ------------------------------ End of SPACE Digest V10 #24 *******************