Return-path: X-Andrew-Authenticated-as: 7997;andrew.cmu.edu;Ted Anderson Received: from beak.andrew.cmu.edu via trymail for +dist+/afs/andrew.cmu.edu/usr11/tm2b/space/space.dl@andrew.cmu.edu (->+dist+/afs/andrew.cmu.edu/usr11/tm2b/space/space.dl) (->ota+space.digests) ID ; Thu, 22 Mar 90 03:06:13 -0500 (EST) Message-ID: Reply-To: space+@Andrew.CMU.EDU From: space-request+@Andrew.CMU.EDU To: space+@Andrew.CMU.EDU Date: Thu, 22 Mar 90 03:05:47 -0500 (EST) Subject: SPACE Digest V11 #177 SPACE Digest Volume 11 : Issue 177 Today's Topics: Re: Getting Drafted Magellan Update - 03/21/90 Comet Austin orbital data needed. Re: Another SR-71 comes to NASA Ames-Dryden Re: Sandia Railgun Re: Freedom finding related to LDEF? Martian Clocks and Calendars Re: Strange flash of light Re: Another SR-71 comes to NASA Ames-Dryden Re: RE: SPACE Digest V11 #145 Re: Strange flash of light ---------------------------------------------------------------------- Date: 21 Mar 90 20:17:18 GMT From: voder!dtg.nsc.com!alan@ucbvax.Berkeley.EDU (Alan Hepburn) Subject: Re: Getting Drafted In article <2972@castle.ed.ac.uk> erci18@castle.ed.ac.uk (A J Cunningham) writes: > >In-Reply-To: Mary Shafer (OFV's message of 20 Mar 90 18:45:30 GMT > > >> The Air Force, Navy, and Marines did NOT draft people. Army troops >> (who may have been drafted) rode in helicopters flown by pilots who >> had volunteered. (Yes, this latter is hair-splitting.) Even in World >> War II, all air crew were volunteers. >> >> The same is true, I understand, of the Royal Air Force, the Royal >> Navy, and the Royal Marines--National Service was in the British Army. > > Well plenty of Army personnel were herded into gliders for >Airborne assaults (e.g. Operation Overlord, Operation Market Garden). I >doubt if that meny of them were volunteers. I accept your point that >American Air crew in WWII were all volunteers although I don't know if >the same was true for British pilots and air-crew and it probably wasn't >the case for Russians. (You did say no-one in your original article) > Tony > >-- I have to interject two points here: 1. Being an ex-paratrooper I can say that I believe the Airborne forces are made up of all volunteers. Even during the draft years you had to volunteer for Jump School. After receiving our wings we were still voluntarily leaving the plane. A paratrooper was never forced to exit; up until the instant he actuall took that lons step, he could sit back down and not jump, with no adverse consequences. I believe the same is true for a combat jump, although the reasons might be more closely inspected. The bottom line is, you can get drafted into the US Army, but not into the US Army Airborne. 2. As far as the US Marines not getting draftees, during the late '60s and early '70s it was common for both the US Army and the Marines to be visible at the induction centre. When I was drafted, three people in line with me were pointed to by the Marine representative with the phrase "You're now a Marine" ringing off the walls. The Marines did receive draftees this way. Of course now, with no draft, nobody gets draftees and all branches are volunteer. -- ------------------------------------------------------------------------------- Alan Hepburn Omne ignotum pro magnifico mail: alan@blenheim.nsc.com My opinions are just that: opinions ------------------------------------------------------------------------------- ------------------------------ Date: 21 Mar 90 23:33:44 GMT From: zaphod.mps.ohio-state.edu!usc!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov!baalke@tut.cis.ohio-state.edu (Ron Baalke) Subject: Magellan Update - 03/21/90 Magellan Mission Status Report March 21, 1990 The Magellan spacecraft is now 107,890,103 miles from Earth, 54,483,662 miles from Venus, and travelling at a heliocentric speed of 60,594 miles/hour. Magellan continues to run in a normal, quiet cruise as it approaches Venus. All STARCALS were successful except for the one on March 9. Gyroscopes B1 and B2 were turned on prior to the Trajectory Course Maneuver (TCM-2) and exhibited erratic current loads which then resulted in their being turned off. It is expected that this condition may improve as the gyros warm up when the spacecraft approaches Venus Orbit Insertion (VOI). The two attitude updates following the turn-on of Gyros B1/B2 averaged 0.125 degrees, about 3 or 4 times the average prior to and following the turn-on. TCM-2 took place at 10 AM (PST) on March 13 and was judged to have been successfully accomplished base on spacecraft telemetry data. All spacecraft telemetry was as expected. Engine burn time was correct and there was no indication of leakage after shutdown. The maneuver was programmed to achieve a 0.509 meter/second change in velocity. The Navigation team has confirmed after analysis of doppler shift data that Magellan achieved a 0.466 meter/second velocity change. This is within one sigma of nominal and is more than adequate for this manuever. Additional manuevers are not required outside of the planned TCM-3 manuever scheduled for July. Ron Baalke | baalke@mars.jpl.nasa.gov Jet Propulsion Lab M/S 301-355 | baalke@jems.jpl.nasa.gov 4800 Oak Grove Dr. | Pasadena, CA 91109 | ------------------------------ Date: 18 Mar 90 03:00:39 GMT From: usna!nardi@uunet.uu.net (LT Peter A. Nardi) Subject: Comet Austin orbital data needed. Sorry if this has been posted already, but could someone please provide me with the following orbital information on Comet Austin: 1.) Size of orbit (in a.u.). (Also called semi-major axis or perihelion dist depending on the orbit type) 2.) Eccentricity. 3.) Inclination of the orbit to the ecliptic. 4.) Longitude of Ascending Node. 5.) Argument of Perihelion. 6.) Date and time (UT) of perihelion. Many Thanks in advance. You can mail directly to me, or post. -==- pete nardi nardi@cad.usna.mil ------------------------------ Date: 21 Mar 90 02:58:29 GMT From: pacbell!unet!radzy!@ames.arc.nasa.gov (Tim Radzykewycz) Subject: Re: Another SR-71 comes to NASA Ames-Dryden In article shafer@skipper.dfrf.nasa.gov (Mary Shafer (OFV)) writes: > When the SR-71 was directly overhead, I could see only one burner > cone, from the right burner. After he passed, I looked up the > tailpipe and saw the orange flame in both burners. I thought I just > didn't see the left cone--sun angle or something. After discussing it > with some other engineers, we've decided that he probably didn't get a > good light on the left burner. I'm told, however, that this flyby was > louder than that of the previous SR-71, which had both burners lit. Sorry for the stupid question, but the comment about the noise level got my curiosity up. Would someone who's in-the-know mind sending me mail about this? The question is this: Could the increase in the noise level be caused BECAUSE only one burner was lit? I mean, if both burners are lit, then there is going to be a certain airstream passing around the plane. If only one burner is going, then the airstream will certainly be different, and the difference might be increased turbulence, which would come out as noise. The more turbulence, the more noise. Is this a reasonable conclusion, or am I way off-base? (no pun intended) -- Tim "radzy" Radzykewycz The Incredible Radical Cabbage radzy@cogsci.berkeley.edu - or - radzy@radzy.net.com ------------------------------ Date: 21 Mar 90 20:46:07 GMT From: mnetor!utzoo!henry@uunet.uu.net (Henry Spencer) Subject: Re: Sandia Railgun In article <1591@nvuxr.UUCP> deej@nvuxr.UUCP (David Lewis) writes: >> A mass driver is a coilgun, or some variant >> thereon, with *recirculating buckets*... > >Hmmm. So Q: How do you decelerate the buckets? Regenerative braking? You have to use a reversed accelerator for the deceleration, as nothing else can handle that kind of velocities. Regenerative braking is obviously desirable, and last I heard, it seemed practical. >What's the ratio of bucket mass to launched mass? ... I don't remember what O'Neill originally figured on. Obviously you'd prefer to minimize bucket mass, to reduce losses even in the presence of regenerative braking. -- Never recompute what you | Henry Spencer at U of Toronto Zoology can precompute. | uunet!attcan!utzoo!henry henry@zoo.toronto.edu ------------------------------ Date: 21 Mar 90 20:49:49 GMT From: mnetor!utzoo!henry@uunet.uu.net (Henry Spencer) Subject: Re: Freedom finding related to LDEF? In article <10876@hoptoad.uucp> tim@hoptoad.uucp (Tim Maroney) writes: >I haven't seen any discussion of the maintenance problems with Space >Station Freedom here, which is surprising given the amount of press. It's well started now; don't be so impatient. :-) >Were these findings related to data from the Long Duration Exposure >Facility? Not that I know of, since there is no data from LDEF yet to speak of -- the scientists are still in the very early stages of investigating the returned payloads. >How come it's just been discovered now? Well, incompetence comes to mind, but then it's been coming to mind for quite a while as the station project approaches its tenth anniversary with no hardware yet built, never mind launched... >Is the chief problem with a "full-time spacewalker" the radiation >exposure? No, that's relatively minor, and the station itself doesn't give that much more shielding. EVA as currently practised is a major hassle, with a lot of overhead effort involved, and is considered relatively dangerous (less redundancy than working inside in shirtsleeves). -- Never recompute what you | Henry Spencer at U of Toronto Zoology can precompute. | uunet!attcan!utzoo!henry henry@zoo.toronto.edu ------------------------------ Date: 21 Mar 90 15:58:11 GMT From: news-server.csri.toronto.edu!utgpu!watserv1!watdragon!watyew!jdnicoll@rutgers.edu (Brian or James) Subject: Martian Clocks and Calendars Possibly a foolish question, but does anybody out there know how the hypothetical manned missions to Mars will deal with the slight difference between the Martian day (88775.3 seconds) and our day (86399.9 seconds)? I imagine most of the trip will use our standard date and time systems, but it strikes me as inconvinient to have the 'official' day slightly out of phase with the local day. James Nicoll ------------------------------ Date: 21 Mar 90 20:17:48 GMT From: zaphod.mps.ohio-state.edu!brutus.cs.uiuc.edu!ux1.cso.uiuc.edu!gibson!dbradley@tut.cis.ohio-state.edu (David Bradley) Subject: Re: Strange flash of light Could this be related to the satellite that was launched by Atlanatis a couple weeks ago? According to a report somewhere (it might have been in this notesfile) the Soviets claim that the satellite was in a deteriorating orbit, and that the US had told the satellite to blow itself up so that none of the pieces would reach the ground intact. This is just a wild guess. I don't even know if the dates are right. -- David Bradley University of Illinois at Urbana Champaign ------------------------------ Date: 21 Mar 90 23:47:16 GMT From: skipper!bowers@ames.arc.nasa.gov (Al Bowers) Subject: Re: Another SR-71 comes to NASA Ames-Dryden In article <383@radzy.UUCP> radzy@radzy.UUCP (Tim Radzykewycz) writes: >> good light on the left burner. I'm told, however, that this flyby was >> louder than that of the previous SR-71, which had both burners lit. >The question is this: Could the increase in the noise level >be caused BECAUSE only one burner was lit? I mean, if both >burners are lit, then there is going to be a certain airstream >passing around the plane. If only one burner is going, then >the airstream will certainly be different, and the difference >might be increased turbulence, which would come out as noise. >The more turbulence, the more noise. Actually, when 980 did its two flybys the first was at about 500-600 ft agl and displaced a couple hundred yards from the building. This pass was only in mil power. The second pass was at the same altitude but was directly over the building with afterburner light happening about 200 yards before passing over the building. Both of these passes were at around 200 knots. Now when 971 flewby it was at about 400+ knots and in afterburner on both passes. The first pass was at about 350 ft agl and the second may have another 100 feet lower than that. In both cases 971 lit the burners about a mile out from the building and it really wasn't apparent that the SR was going to miss the building until the last 5 or 10 seconds. I think the proximity to the aircraft had more to do with the sound level as may the velocity and how far the pilots had the throttle pushed up. In all cases it was quite an adrenaline rush. -- Albion H. Bowers bowers@elxsi.dfrf.nasa.gov ames!elxsi.dfrf.nasa.gov!bowers NASA Ames-Dryden Flight Research Facility, Edwards, CA Aerodynamics: The ONLY way to fly! Live to ski, ski to live... ------------------------------ Date: 21 Mar 90 16:00:33 GMT From: zaphod.mps.ohio-state.edu!sol.ctr.columbia.edu!IDA.ORG!pbs!pstinson@tut.cis.ohio-state.edu Subject: Re: RE: SPACE Digest V11 #145 IIn article , F026@CPC865.EAST-ANGLIA.AC.UK ("P D JONES, CRU") writes: > Could you please not send any more messages to this account. The previous > holder, Mike Salmon, no longer works here. Thanks. I believe you have to disengage from the network at your end. Ask someone in your computer sevices dept., if you have one. As long as your "fawcet" is open, messages will flow through. ------------------------------ Date: 22 Mar 90 00:00:40 GMT From: snorkelwacker!usc!elroy.jpl.nasa.gov!jpl-devvax!lwall@bloom-beacon.mit.edu (Larry Wall) Subject: Re: Strange flash of light In article <1990Mar21.164655.2788@utzoo.uucp> henry@utzoo.uucp (Henry Spencer) writes: : In article <1769@lakesys.lakesys.com> jtk@lakesys.UUCP (Joseph T. Klein) writes: : >This is an odd event. Why do the space/astro people shy away from talking : >about these events? ... : : Probably because the space/astro people are waiting for detailed technical : reports so they can argue from known facts, a constraint that has never : bothered the UFO people... : -- : Never recompute what you | Henry Spencer at U of Toronto Zoology : can precompute. | uunet!attcan!utzoo!henry henry@zoo.toronto.edu Given the content of the Henry's article, a much more appropriate signature saying would have been: "Never precompute what you can't recompute." A good summary of the scientific method... Besides, the original statement is slightly inaccurate. It should say "Never recompute what you can precompute and remember easily." Sometimes cycles are cheaper than bytes. Larry Wall lwall@jpl-devvax.jpl.nasa.gov ------------------------------ End of SPACE Digest V11 #177 *******************