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 ; Wed, 6 Jun 1990 01:46:18 -0400 (EDT) Message-ID: Precedence: junk Reply-To: space+@Andrew.CMU.EDU From: space-request+@Andrew.CMU.EDU To: space+@Andrew.CMU.EDU Date: Wed, 6 Jun 1990 01:45:49 -0400 (EDT) Subject: SPACE Digest V11 #494 SPACE Digest Volume 11 : Issue 494 Today's Topics: Re: Jupiter Sodium Cloud "CCD imagers in HST" from EE Times Van Allen Belts Re: DSN Reliability and Resources Question Re: HAWAII AND STAR WARS NASA Headline News for 06/05/90 (Forwarded) Payload Status for 06/05/90 (Forwarded) SPACE Digest V11 #489 Administrivia: Submissions to the SPACE Digest/sci.space should be mailed to space+@andrew.cmu.edu. Other mail, esp. [un]subscription notices, should be sent to space-request+@andrew.cmu.edu, or, if urgent, to tm2b+@andrew.cmu.edu ---------------------------------------------------------------------- Date: Tue, 5 Jun 90 13:38 EDT From: "CURATOR, B.U. DEPARTMENT OF ASTRONOMY" Subject: Re: Jupiter Sodium Cloud In response to: *Date: 31 May 90 18:45:47 GMT *From: thorin!homer!leech@mcnc.org (Jonathan Leech) *Subject: Re: Jupiter and Sodium Cloud...... *In article <88023FBBB03F203E9B@buasta.bu.edu> FRANK@BUASTA.BU.EDU ("CURATOR, * B.U. DEPARTMENT OF ASTRONOMY") writes: *>Last November, a team of astronomers from Boston University went to McDonald *>Observatory in Texas to image this cloud in "sodium light", which is easier *>to image than sulfur or some of the other elements Io spews out. * Does this lie in one of the frequencies spewed out by the sodium *lighting astronomers are opposed to? * Jon Leech (leech@cs.unc.edu) __@/ The emission which was observed to be coming from the Jovian environment is the neutral sodium D1,D2 doublet at 5890 and 5896 angstroms. Sodium lamps emit light at these same wavelengths, hence their orange appearance. We had enough trouble with the naturally occuring atmospheric sodium emissions and any excessive sodium lamp interference would have made the observations impossible. Fortunately, McDonald Observatory has minimal sodium light pollution and so it was a good place to make observations at these wavelengths. Brian Flynn Boston University Department of Astronomy P.S. Thus another example of why we continually fight for dark skies! - FFS ------------------------------ Date: 5 Jun 90 22:18:28 GMT From: mtndew!friedl@uunet.uu.net (Stephen J. Friedl) Subject: "CCD imagers in HST" from EE Times From _EE Times_, 4 June 1990, pg 33 (reproduced w/o permission) TI CCD Imagers Give Hubble Better Vision - Greenbelt, MD The first image returned from the Hubble Space Telescope was matched with a similar image from a telescope in Chile, and proved to be distinctly clearer. Texas Instruments supplied the thermoelectrically-cooled CCD imager arrays on the Hubble; they are set up in four tiled, 2048x2048 pixel imagers. Ground-based observatories have telescopes based on lower quality (fallout) CCD imagers, also often supplied by TI. -- Stephen J. Friedl, KA8CMY / Software Consultant / Tustin, CA / 3B2-kind-of-guy +1 714 544 6561 / friedl@mtndew.Tustin.CA.US / {uunet,attmail}!mtndew!friedl "I will defend to your death my right to my opinion" - me ------------------------------ Date: Tue, 5 Jun 90 08:10:32 PDT From: space_digest%utdssa.dnet%utadnx@utspan.span.nasa.gov X-Vmsmail-To: UTADNX::UTSPAN::AMES::"space+@andrew.cmu.edu",HAIRSTON Subject: Van Allen Belts Today's (June 5) New York Times has a good article about the Van Allen Belts , the South Atlantic Anomaly, and all the problems they're causing for NASA and various satellites. Check it out. I'm still digging for a list of articles about the belts and the magnetosphere in general and I'll post that at the end of the week. Marc Hairston--Center for Space Sciences--University of Texas at Dallas SPAN address UTSPAN::UTADNX::UTD750::HAIRSTON "It is better to light a single candle than to get all hot and sweaty trying to light a grape."--C. Barsotti ------------------------------ Date: 5 Jun 90 05:10:44 GMT From: unmvax!nmt.edu!nraoaoc@ucbvax.Berkeley.EDU (Daniel Briggs) Subject: Re: DSN Reliability and Resources Question In article khai@amara.uucp (S. Khai Mong) writes: >A bunch of simple questions: >What are the resources of DSN in terms of dishes and sites? > >What is the expected reliability and redundancy during really critical >periods? > >Could radio astronomy telescopes be pressed into service? Yes, they can and have used existing radio astronomy sites to supplement the DSN. Since the decodable bit rate that you can sustain is a direct function of the sensitivities of your receiver, (at least in the low signal case, anyway), more collecting area directly translates into more pictures. This was critical during the Voyager encounter with Neptune. The DSN was augmented with the VLA here in New Mexico, and with the Parkes 64m telescope in Australia. From our point of view, it was a terrific deal! NASA provided us with the equipment that we needed to track Voyager, and we provided them with about a month of observing time. We got about $8M worth of new equipment, and they got about 30% more images back than they would have without us in the net. Both sides proclaimed themselves *extremely* pleased with the results. With budgets the way that they are, there is no way that we could have afforded half the stuff that NASA bought us, some of it very badly needed indeed. The reliability issue is kind of interesting, though. NASA has very different standards of reliability than we do. We had been running at about 80% reliability or thereabouts before the encounter. (Memory is vague, so don't take this as gospel, but I think that was 80% of the time we were *supposed* to be on the air. That is, scheduled down time wasn't included in that figure.) NASA wanted the reliability above 98%. That costs a lot of money that we just didn't have by ourselves. I mean, if we have a lightning strike and lose an hour of observing, we just reschedule. If that happens to the DSN during an encounter, you are big time SOL. Of the $8M that was spent on the upgrade, a little less than half went to buying a new receiver system that could receive Voyager. (This X-band system is now the most sensitive of the half dozen bands that we have available. There is a *lot* of good science that has come out of it. Not the least is the fact that we now share a frequency with Goldstone. We can now do radar reflection experiments with them. They transmit, we receive.) They remaining money all went into upgrading our reliability. We got a first class lightning protection system for the control building. We got a brand new set of online control computers. They brought in a few very pricey specialists who managed to fix a few software bugs that had been with us as long as the array has been operational. We got not one, but two new backup power generators. Neither NASA's way of operating not ours is *wrong*, but both are quite *different* from each other. The operating philosophies evolved under an entirely different set of constraints. In our case, maximizing the science per buck meant more equipment, but less reliability. NASA goes the other way. Certainly by the time they had finished the upgrade, we felt a little Au plated. (And even though I expect a few snide remarks about that last sentence, I found the encounter to be a quite educational experience. Gold plated toilets are one thing, but reliable receivers are another. Reliability is expensive, but there are very good reasons for making single point failure equipment as reliable as possible. In short, I could see where NASA was coming from during all of this.) -- This is a shared guest account, please send replies to dbriggs@nrao.edu (Internet) Dan Briggs / NRAO / P.O. Box O / Socorro, NM / 87801 (U.S. Snail) ------------------------------ Date: 4 Jun 90 15:29:53 GMT From: att!watmath!watserv1!utgpu!utzoo!henry@ucbvax.Berkeley.EDU (Henry Spencer) Subject: Re: HAWAII AND STAR WARS In article <602@imokay.dec.com> borsom@imokay.dec.com (Doug Borsom) writes: >The fact (if true) that Cape Kennedy includes a thriving wildlife >refuge is irrelevant to the Hawaii question unless the two >eco-systems are very similar and the proposed use (in the largest >sense of the word) of the Big Island site is very similar... You're confusing proofs with good examples. The fact that Kennedy Space Center (there is no Cape Kennedy nowadays) includes a thriving wildlife refuge (it does; I've been there) is not sufficient to prove that the Hawaii launch site would have similar results. However, it *is* quite sufficient to shoot down the claim that vast ecological devastation would inevitably ensue. >So far, most postings on both sides have dealt with the assesment >of the ecological impact with the kind of simplicity that ... >well, let's say that Carl Sagan has been accused of in writing >his Sunday Supplement articles about subjects far outside his area >expertise. Subject to constraints of honesty and good taste, one does one's best to match the tone and intellectual respectability of the original posting. -- As a user I'll take speed over| Henry Spencer at U of Toronto Zoology features any day. -A.Tanenbaum| uunet!attcan!utzoo!henry henry@zoo.toronto.edu ------------------------------ Date: 5 Jun 90 16:27:00 GMT From: trident.arc.nasa.gov!yee@ames.arc.nasa.gov (Peter E. Yee) Subject: NASA Headline News for 06/05/90 (Forwarded) ----------------------------------------------------------------- Tuesday, June 5, 1990 Audio Service: 202/755-1788 ----------------------------------------------------------------- This is NASA Headline News for Tuesday, June 5........ Kennedy Space Center workers are preparing the Space Shuttle Columbia with sensors for an additional test to find the source of a liquid hydrogen leak that scrubbed last week's launch of STS-35. A liquid hydrogen fill test on the orbiter's main propulsion system is scheduled for Wednesday morning. Technicians hope to detect the leak source during the transition from slow to fast fill. The orbiter will remain at launch pad 39- A and the Rotating Service Structure will be retracted during the test. ******** The Magellan spacecraft is performing well in cruise mode following the successful completion of a cruise mapping test last Friday. On completion of the final "orbit" of the mapping test, the radar was turned off and the spacecraft subsystems were returned from orbital operations to cruise configuration. The spacecraft is 108 million miles from Earth traveling at 76,000 miles per hour. It is scheduled to reach Venus this August. ******** Aerospace Daily reports an Administration official confirmed that Vice President Dan Quayle met with Soviet leader Mikhail Gorbachev Friday to discuss space. The story reports the National Space Council, chaired by Quayle, is drafting the scope of international participation in the President's Space Exploration Initiative. According to the story, offers to participate in missions to the moon and Mars will be extended to Japan and European countries already involved in cooperative space programs with the U.S., but Soviet participation will not be ruled out. ******** Japan's Agency of Industrial Science and Technology may build a robot for Space Station Freedom, according to Reuters news service. The Japanese government will decide this August whether to develop, build and launch a $130 million mechanical "handyman" scheduled for the year 2000. The robot would be used to assemble structures and repair machinery in space. ******** A second Pegasus launch by Orbital Sciences Corporation is scheduled for early this fall, according to Space Fax Daily. The payload will be seven microsatellites currently under construction by Defense Systems, Inc. It will be for the Defense Advanced Research Projects Agency. --------------------------------------------------------------- Here's the broadcast schedule for Public Affairs events on NASA Select TV. All times are Eastern. Tuesday, June 5........ 12:00-2:00 P.M. NASA Video Productions. Birth and death of a star. Supernova 2. Life and the solar system. Robotics in the Space Station. Computer animation movies on the Earth and Mars. Neptune encounter highlights. Wednesday, June 6....... 2:00 P.M. Voyager I Solar System "Family Portrait" news conference. Thursday, June 7........ 11:30 A.M. NASA Update will be transmitted. ----------------------------------------------------------------- All events and times are subject to change without notice. These reports are filed daily, Monday through Friday, at 12:00 P.M. EDT. This is a service of the Internal Communications Branch, NASA HQ. Contact: JSTANHOPE on NASAmail or at 202/453-8425. ----------------------------------------------------------------- NASA Select TV: Satcom F2R, Transponder 13, C-Band 72 Degrees West Longitude, Audio 6.8, Frequency 3960 MHz. ----------------------------------------------------------------- ------------------------------ Date: 5 Jun 90 16:28:45 GMT From: trident.arc.nasa.gov!yee@ames.arc.nasa.gov (Peter E. Yee) Subject: Payload Status for 06/05/90 (Forwarded) Daily Status/KSC Payload Management and Operations 06-05-90. - STS-35 ASTRO-1/BBXRT (at Pad-A) - Launch countdown and scrub/turnaround support continue today. -STS-40 SLS-1 (at O&C) - Mechanical and fluid preps for CITE testing along with MVAK training continues. - STS-41 Ulysses (at ESA 60) - The RTG walkthrough at Pad-B will continue today. - STS-42 IML-1 (at O&C) - Rack, floor, and module staging along with water servicer validations are continuing. - STS-45 Atlas-1 (at O&C) - Orthogrid installation continues. - STS-46 TSS-1 (at O&C) - Coldplate lifter beams were modified third shift today. - STS-47 Spacelab-J (at O&C) - Rack 4 staging will be performed today. - STS- 55 SL-D2 (at O&C) - Rack 12 staging continues. - STS-LON-3 HST M&R (at O&C) - ORUC interface testing will be active today along with MLI installation. ------------------------------ Date: Tue, 05 Jun 90 08:37:41 CDT From: CC731CC To: Subject: SPACE Digest V11 #489 PLEASE! Remove me from this list. Sorry for the interruption. -Brian ------------------------------ End of SPACE Digest V11 #494 *******************