Date: Mon, 16 Nov 92 05:00:03 From: Space Digest maintainer Reply-To: Space-request@isu.isunet.edu Subject: Space Digest V15 #425 To: Space Digest Readers Precedence: bulk Space Digest Mon, 16 Nov 92 Volume 15 : Issue 425 Today's Topics: COSTAR N-1 giant Moon rocket photo in *AvLeak* Please clean up | Putting telescopes on the moon Shuttle replacement Shuttle replacement, STS-52 half-full Shuttle Status for 11/13/92 (Forwarded) Space suit research? Welcome to the Space Digest!! Please send your messages to "space@isu.isunet.edu", and (un)subscription requests of the form "Subscribe Space " to one of these addresses: listserv@uga (BITNET), rice::boyle (SPAN/NSInet), utadnx::utspan::rice::boyle (THENET), or space-REQUEST@isu.isunet.edu (Internet). ---------------------------------------------------------------------- Date: 15 Nov 92 13:56:50 GMT From: "Frederick A. Ringwald" Subject: COSTAR Newsgroups: sci.space In article roberts@cmr.ncsl.nist.gov (John Roberts) writes: > Are they the same company that makes mason jars? (The logo appears to > be the same.) They are indeed. Also aluminum cans - next time you see a Coke can, look for the same, familiar logo. I visited their plant in Boulder, Colorado, in 1989 summer, as part of a Solar physics summer school held by the National Center for Atmospheric Research/High Altitude Observatory. They showed us the CREES satellite, being assembled, and the technology for the IRAS and other micro-g liquid helium dewars, which they developed. I'm not sure what this has to do with applesauce or currants, but who knows, with big corporations? ------------------------------ Date: Sat, 14 Nov 1992 21:04:31 GMT From: Dennis Newkirk Subject: N-1 giant Moon rocket photo in *AvLeak* Newsgroups: sci.space In article phfrom@nyx.uni-konstanz.de (Hartmut Frommert) writes: > >Can someone make it a .GIF and upload on a ftp server ? >-- > Hartmut Frommert I know 3 GIF's of the photo showing closeups of portions, and the complete photo were put on Compuserve a couple of months ago in the space forum new uploads section I think. Dennis Newkirk (dennisn@ecs.comm.mot.com) Motorola, Land Mobile Products Sector Schaumburg, IL ------------------------------ Date: Sun, 15 Nov 92 15:23 FWT From: "Andre HECK" Subject: Please clean up | To anyone feeling concerned: I have subscribed to this space-digest not so long ago and I am appalled by the quantity of rubbish I have been receiving since. Is no-one filtering the inputs for this digest? Frankly pollution of information seems to be an ignored concept here. There is an enormous duplication of text in the sense that messages answering others repeat in extenso the contents of the latter ones. A concise reference would do. If reports on spacecraft status are perfectly in line with what one could expect from such a space-digest, the exchange on how to use slide-rules (v15 #420) is definitely out of place. Please, are we still kids jumping on line without thinking it over twice beforehand? I shall maintain my subscription for some time, but if the situation does not improve, I shall signoff as I am convinced many did before without voicing their reasons. Regards. AH. ----------------------------------------------------------------------- Prof. Andre HECK -+- * Phone (direct) +33-88.35.82.22 Observatoire Astronomique * Phone (Secretary) +33-88.35.82.18 11, rue de l'Universite -+- * Fax (direct) +33-88.49.12.55 F-67000 Strasbourg * -+- Fax (Secretary) +33-88.25.01.60 France -+- * * Telex 890506 starobs f ----------------------------------------------------------------------- As this e-mail account might be shut down in a near future, please start using preferably the "direct" fax number above. Thank you. ----------------------------------------------------------------------- ------------------------------ Date: Sun, 15 Nov 92 10:26:10 EST From: John Roberts Subject: Putting telescopes on the moon -From: arnold@clipper.ingr.com (Roger Arnold) -Subject: Re: Putting air on the moon -Date: 13 Nov 92 17:16:46 GMT -Organization: Intergraph Advanced Processor Division - Palo Alto, CA -In article roberts@cmr.ncsl.nist.gov (John Roberts) writes: ->If that's correct, then a 1000 km array on the moon could potentially give ->a resolution at 10 light years of about 50 km. (Imagine mapping the continents ->on the planets of nearby star systems!) [..] -Sorry, won't work. Not unless the individual telescopes in your array -are pretty spectacular instruments in their own right. -You need around 10 meters of unobscured aperture, with a mirror -perfectly figured and smooth to .01 lamda, to keep the light from the -planet from being lost in the statistical noise of light diffracted -from the primary. And even that's only adequate for the dozen or so -nearest stars. Well, one good sign: the precision of the HST optical system (primary plus secondary) is on that order. (Note that I didn't say *accuracy*. :-) Of course the HST primary isn't that big. -The problem is that, for a terrestrial planet at optical wavelengths, -the light any telescope receives from the planet will be ten orders -of magnitude below (one ten-billionth) the light from the primary. If -planet and primary were of equal brightness, a one meter space tele- -scope could resolve them. But as it is, it would take nearly perfect -diffraction-limited optics of ten times that aperture to concentrate -the planet's light enough to detect it above the far-field light haze -from the primary. -But, you ask, so what? Won't mixing the signals from the combined -telescopes in the array isolate the light from the planet? Well, yes -and no. You can boost the signal-to-noise ratio by an amount that's -proportional to the number of telescopes in the array. That might -allow you to detect the presence of the planet, where you couldn't -otherwise. But unless you start with a pretty clean signal in the -first place, there will be far too much noise to allow anything like -imaging of continents. Would speckle interferometry, or integration of the incoming signals over very long periods of time (hours to weeks) help with reception? (Other than the fact that planets move over such time intervals.) I think you've made your point that the resolution formula can't be extended out to infinity. I'd be interested in how far it *can* be extended with, say, 100 high-precision 10-meter optical telescopes. John Roberts roberts@cmr.ncsl.nist.gov ------------------------------ Date: Sat, 14 Nov 92 20:46:28 PST From: Brian Stuart Thorn Subject: Shuttle replacement Newsgroups: sci.space.shuttle,sci.space Very good article, Mike. I think you covered all the bases quite well, except that I would like to add a note or two abosatellite launches. In the best hindsight is 20/20 fashion, I think it was a terrible mistake to offload all those payloads from the Shuttle in 1986-88. Of our unmanned boosters, only Delta seems to be operating reliably. It is my opinion that NASA should have continued using Shuttle for as many payloads as possible, while diverting as much booster development money as possible into NLS or some other unmanned launch system. Instead, we got Titan IV, a boondoggle in the finest Space Shuttle tradition. At least Space Shuttle is flying... and regularly. How much money has the Air Force poured into that program? And for what, a new monument at Launch Pad 41? The thing was on the pad so long it got rusty. Meanwhile, Shuttles are being launched half-empty (i.e., STS-52) Am I the only one who sees something wrong there? Titan IV has flown 6 times since June, '89. STS has flown 22 missions in that time frame. Of course, STS is more expensive. But its already paid for, and all that money for Titan IV (not including Martin's Titan III program) has bought us little. Even old faithful Atlas-Centaur is in a world of trouble, but it's trouble is mostly due to a Centaur derivative meant for Shuttle. It seems to me that in 1992, Space Shuttle is offering one of the best returns on investment in the space community! -Brian ------------------------------ Date: 15 Nov 92 06:05:18 GMT From: William Li Subject: Shuttle replacement, STS-52 half-full Newsgroups: sci.space.shuttle,sci.space rticle <69532@cup.portal.com> BrianT@cup.portal.com (Brian Stuart Thorn) writes: > >rusty. Meanwhile, Shuttles are being launched half-empty (i.e., STS-52) >Am I the only one who sees something wrong there? As someone who worked on STS-52, I feel obliged to comment on this perception that STS-52 was launched half-empty. I worked Space Vision System (SVS) support, SVS being one of 7 experiments flown as part of CANEX-2. SVS uses the orbiter's own cameras to track payloads and other artificial targets, providing the human operators with highly accurate, real-time positional and velocity feedback in, for example, remote manipulator operations or orbiter docking procedures. STS-52 was a characterisation flight for the SVS, designed to examine the interactions of the orbiter system with the mature (~20-30 yrs) technology of the SVS. As part of the SVS operations, the MS's Lacy Veach and Tammy Jernigan used the SVS to provide feedback as they maneovered a lightweight satellite (the Canadian Target Assembly, or CTA) around and above the payload bay. (The CTA was a black domino-looking thing, about 4' wide, 8' high, and 19" deep) These operations were designed to demonstrate various skills which would be required for Space Station Freedom assembly. One of these operations consisted of berthing and unberthing the CTA from its cradle. The inputs to the SVS consist of video from the orbiter cameras, the primary cameras for STS-52 ops being cameras Alpha and Delta, the two forward bulkhead cameras. It would have rendered operations difficult, to say the least, if the view from the forward bulkhead cameras of the cradle was obstructed by, say, a sun shield containing another satellite for launch. The aft (rear) cameras could not be used for this particular unberthing because their view was obstructed by the LAGEOS sun shield. As well, such obstructions would have forced operations to move out much further above the payload bay because of remote manipulator flight rules about proximity to structures. This change in procedure would have limited our ability to study phenomena such as orbiter flex due to thermal gradients in orbit. (the shuttle is not a perfectly rigid platform) In short, the Space Vision System operations required the elbow space in the payload bay. Unfortunately, when no SVS ops were going on, the sim views of the orbiter payload bay showed a stowed remote manipulator system and a tiny black domino (the CTA) stowed in its cradle attached to a GaS beam. >is mostly due to a Centaur derivative meant for Shuttle. It seems to me >that in 1992, Space Shuttle is offering one of the best returns on >investment in the space community! >-Brian I agree. These are very exciting times to be involved with the space business. I think the Space Shuttle program is back on track. William Li Disclaimer: The comments made above do not constitute an official statement from the Canadian Space Agency, although a similar-sounding statement was issued by the Canadian Astronaut Program in response to the same critique of STS-52 (ie, half-empty). I am now back at school, and no longer work for the Canadian Space Agency. These comments also do not represent the views, express or implied, of anyone at the School of Engineering Science at Simon Fraser University, at which I am a student. They are a result of my own observations and deductions following a year of work for CSA on the SVS. Any feedback can be directed to me through UseNet or by email at wli@ensc.sfu.ca. This article was not intended to flame any one, thing, or small animal. ------------------------------ Date: 15 Nov 92 04:27:06 GMT From: Brian Stuart Thorn Subject: Shuttle Status for 11/13/92 (Forwarded) Newsgroups: sci.space STS-52, STS-53, STS-54, and STS-55. Well, they'll be in order (as things stand now) but they're still one flight off. STS-52 was Flight 51. I think, next summer with the ACTS mission, we'll get the program back on track... in order and on time. Of course, then the Hubble Revisit (STS-63, moved forward on the schedule) will throw us off. I believe STS-44 a year ago was actually the 44th flight. We may never see such a coincidence again! -Brian ------------------------------ Date: 15 Nov 92 05:31:27 GMT From: Pat Subject: Space suit research? Newsgroups: sci.space In article roberts@cmr.ncsl.nist.gov (John Roberts) writes: >-was a Very Good Thing. > >Thanks for the confirmation. 8.4 psi sounds plausible - 10.2 seemed a little >high, since they always depressurize somewhat in preparation for an EVA. > >Anyone recall whether there was an unusually high rate of equipment >failure for that flight that might be associated with the lower pressure? >(Other than the fax machine jamming as usual, of course. :-) I remember >that one or more of the cargo bay lights burned out, but that wouldn't >be pressure-related. > What's the big push for a earth normal type atmosphere? apollo, etc, ran fine on low pressure pure O2, does better pressure greatly improve cooling. or are there long term bio effects???? ------------------------------ End of Space Digest Volume 15 : Issue 425 ------------------------------