Date: Sun, 7 Mar 93 05:18:06 From: Space Digest maintainer Reply-To: Space-request@isu.isunet.edu Subject: Space Digest V16 #285 To: Space Digest Readers Precedence: bulk Space Digest Sun, 7 Mar 93 Volume 16 : Issue 285 Today's Topics: Charon (2 msgs) Mars exploration plans, and absence thereof Shuttle budget (2 msgs) space news from Jan 11 AW&ST The courage of anonymity (6 msgs) The Planetary Society and Mars Exploration Water resupply for SSF (?) Without a Plan 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: Sat, 6 Mar 1993 23:42:00 GMT From: Dave Tholen Subject: Charon Newsgroups: sci.space Arthur Chandler writes: > Does anyone know if there any plans, in the near or far future, to > send a probe to or near Charon, the moon/coplanet of Pluto? Yes, there are plans. The mission, currently known as the Pluto Fast Flyby, is not yet funded at the Congressional level, but NASA has been spending money on development of the mission concept and design. In fact, on February 10 they released a Research Announcement calling for Instrument Definition for the Pluto Fast Flyby. Innovative technology is needed to reduce the mass and power requirements of the payload to meet restrictions imposed by the mission planners. Launch could be around the turn of the century, with arrival only seven years later. Flyby velocity would be significantly less than Voyager 2's past Triton, however. Twin spacecraft are envisioned, with encounter dates separated by perhaps as much as a year, to permit global imaging, which would be impossible to do at high resolution with a single spacecraft, given the flyby velocity and the slow rotation rate of the planet. ------------------------------ Date: 7 Mar 1993 00:26 UT From: Ron Baalke Subject: Charon Newsgroups: sci.space In article , tholen@galileo.ifa.hawaii.edu (Dave Tholen) writes... >Arthur Chandler writes: > >> Does anyone know if there any plans, in the near or far future, to >> send a probe to or near Charon, the moon/coplanet of Pluto? > >Yes, there are plans. The mission, currently known as the Pluto Fast Flyby, >is not yet funded at the Congressional level, but NASA has been spending >money on development of the mission concept and design. Dan Goldin has strongly supported the Pluto Fast Flyby mission. On one of his trips to JPL last year, Goldin handed Rob Staehle (the project manager for Pluto Fast Flyby) a check for $5 million dollars for the project. He also emphasized that he wants to see the mass of the spacecraft be reduced to 110kg. ___ _____ ___ /_ /| /____/ \ /_ /| Ron Baalke | baalke@kelvin.jpl.nasa.gov | | | | __ \ /| | | | Jet Propulsion Lab | ___| | | | |__) |/ | | |__ M/S 525-3684 Telos | It's kind of fun to do /___| | | | ___/ | |/__ /| Pasadena, CA 91109 | the impossible. |_____|/ |_|/ |_____|/ | Walt Disney ------------------------------ Date: Sun, 7 Mar 1993 07:05:02 GMT From: Nick Szabo Subject: Mars exploration Newsgroups: sci.space gary@ke4zv.uucp (Gary Coffman) writes: >In 1969 no one had even heard of VR telepresence. We still don't do it >very well. One of the larger problems even today is dealing with the >time lag for feedback. Round trip speed of light time to the Moon is >on the order of 2.5 seconds, it's over 4 minutes round trip to Mars >at closest approach. Decoupling your movement commands with your >perceptions by such a temporal displacement makes a mockery of >telepresence. In some ways yes, in some ways no. Check out the MIT Press journal _Prescence_, especially the paper in the first volume on "teleprogramming". A good VR simulations is combined with a modicum of on-site knowledge of the near-term environment, and a good error-notification and correction protocol between the user and the telebot. This is mostly being tested for 3-10 sec. delays, which are typically for oil industry undersea sonar telepresence, but similar principles can be used for longer delays. The most state-of-the-art VR is currently used by the Army for virtual military exercises, and it won't be long before telepresence is used in battle. >A combination of the ever mythical AI You never cease to attack strawmen, do you? (a) techniques associated with AI, such as robots, expert systems, neural nets, etc. are a thriving $multi-billion commercial industry, not "mythical", and (b) there is nothing about telepresence that requires theoretical breakthrough; it's primarily a matter of software hacking and improving hardware thruput. >VR >telepresence seems unlikely to play a major role in forthcoming >missions. You'll have to let astronaut Pete Conrad know, so he can stop developing his VR telepilot system for DC-X. -- Nick Szabo szabo@techboook.com ------------------------------ Date: Sun, 7 Mar 1993 01:05:18 GMT From: Henry Spencer Subject: plans, and absence thereof Newsgroups: sci.space In article <6MAR199305120172@kelvin.jpl.nasa.gov> baalke@kelvin.jpl.nasa.gov (Ron Baalke) writes: >The Grand Plan for exploring the solar system is a simple four step process: > > 1. Flyby > 2. Orbiter > 3. Unmanned Landing > 4. Manned Landing What's step 5? Or is one manned landing the end of exploration for any planet? What are the priorities for the various steps on the various planets? Is there some rational reason, for example, why we continue to spend billions on the outer planets when our own Moon -- closer, easier, and of far more near-term significance to spaceflight -- remains mostly unexplored? Major gaps in our knowledge of the Moon could be filled for a small fraction of Cassini's budget. (Note, I'm not claiming that we should *ignore* the outer planets in favor of the Moon, but neither should we ignore the Moon in favor of the outer planets, which is more or less what we are doing.) For example, surely the Moon should be at least as well mapped as Mars, which it's not. Where do rovers fit in? Or geochemical orbiters (a step which has never been done for the Moon)? Or atmosphere probes? Surely steps 2 and 3 need to be broken down into far more detail, to say nothing of step 4 and whatever follows it. This is not a plan; it is just another way of saying "easy things first, hard things later". That's sensible, but it's not enough. You do not have a plan until you can say "mission XYZ is essential to long-lead-time items in the long-term plan, so it has higher priority than things that have better short-term return"... and make it stick. As a case in point, if you are serious about step 4 being part of the process of planetary exploration, it is clear that we need better data on the medical effects of long-term free fall and low gravity, because manned missions even in the inner solar system will be lengthy. Since "long term" means years, and we're going to need more than one test run to get detailed information, a biomedical space station is clearly a vital long-lead item for planetary exploration, and should have a fairly high priority, because we need to start *now* if we're going to have solid data in time for manned missions several decades hence. This idea is, shall we say, *unpopular* in the planetary-exploration community... which indicates just how seriously this "plan" is taken, vague and indefinite though it is. >If you look at this closely, you'll realize that the Galileo and >Cassini missions are the second step in the Grand Plan and are the follow ons >to Voyager... So when do we see unmanned landers for Jupiter and Saturn? Which is more important? How do their priorities compare to, say, Mars sample return? Will these two missions, one per planet, exhaust what can be done with orbiters? Do we fly a geochemical orbiter around Callisto before or after a manned Mars mission? At the current stage of things, a plan cannot be expected to give detailed and final answers to such questions... but it should be able to give rough and tentative ones, based on an idea of the desired sequence of events in the absence of major surprises. No such tentative answers can be found, because there is no plan. >With Venus, we sent the flyby missions with Mariner 2 and >Mariner 10; we've done the orbiters with Pioneer Venus and Magellan, so >the next logical step would be to send a lander (the Soviets have sent >landers, but the US hasn't). The other logical possibility would be to decide that Venus is not worth major further effort at this point, which is the sort of thing that a plan might do. Or it might decide that Venus deserves to stay at the orbiter stage for a while, since there are a number of questions that can still be answered from orbit, and building practical Venus landers is hard. (As a case in point of such questions, there were a number of atmosphere experiments and such slated for VOIR which were scrapped to save money on Magellan.) >The Fast Pluto Flyby mission is the start of the first step for Pluto. What is the relative priority of the advanced-propulsion work that will be needed to go beyond step 1 for Pluto? Given how much even PFF is going to have to spend on launchers -- millions of dollars per kilogram of probe weight, assuming they use Titan -- surely this should have a high priority as a crucial long-lead item for outer-planets exploration. There is good reason to mount PFF now with off-the-shelf technology, since Pluto's atmosphere won't wait, but there seems to be a notable lack of strategic planning here for other missions. >The proposed MESUR mission is step 3 >for Mars and will eventually help pave the way to a manned landing. Will that be before or after the first manned asteroid expedition? (If you pick an Earth-approaching asteroid, that mission is easier and has a higher payoff in some ways.) >It may not always be obvious but there is plan, and it has been in effect >for over 30 years. This plan is so un-obvious that it's awfully close to invisible. -- C++ is the best example of second-system| Henry Spencer @ U of Toronto Zoology effect since OS/360. | henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: Sun, 7 Mar 1993 00:23:08 GMT From: Henry Spencer Subject: Shuttle budget Newsgroups: sci.space In article neff@iaiowa.physics.uiowa.edu (John S. Neff) writes: >The launches are from facilities owned by the government and are supervised >by the Air Force whi is responsible for destroying any vehicle that >is off course. Thus the government is liable not the company that provides >launch services. Sorry, the launch supplier needs insurance before it can even apply to use the facilities, although I believe the government does cover any liability over $250M (partly because the most important component of this is possible damage to government facilities). The USAF does *not* take financial responsibility just because it is in charge of range safety. >In addition to the Titan IV the Air force owns a large number of ballistic >missles. Some of these have been converted to other uses such as SDI >projects. If the Air Force wants to use a Delta II or an Atlas Centaur II >not in their current inventory they would have to buy one from >either McDonnell Douglas or General Dynamics as you have said. As far as I know, the only USAF ballistic missiles still in inventory are the Titan IIs, which are currently being refurbished under launch contracts with Martin Marietta. Note, this is not the USAF doing the launches -- the USAF is supplying an important item of hardware to Martin Marietta, which is selling launch services to the USAF. This is the law of the land, as of a couple of years ago: the USAF is forbidden to operate its own launch services when the equivalent is commercially available. Ditto NASA. >If there is to be a purely commercial launch service there has to be >sufficient commecial business for it to exist. Why should the government >use a commecial launch service when they have their own? With the exceptions of Titan IV and the Shuttle, the government *doesn't* have its own launch services any more. It is already buying commercial launch services quite extensively. Mars Observer went up on a commercial Titan III plus a commercial TOS upper stage. All Delta and Atlas launches are now commercially provided. Pegasus, Taurus, Conestoga, et al, have always been 100% commercial, and the government is buying a fair number of them. I'm not sure whether Scout has completely made the transition yet, but it seems to be pretty much a dead program anyway (in the US). Both the space-station people and the Pluto-Fast-Flyby people have quite seriously broached the idea of commercial buys of Russian launchers. There *is* still a problem with NASA putting things onto the shuttle when they could perfectly well go up on commercial launch services. That is an argument in *favor* of getting NASA out of the launch business. >the Department of Defense is one of the biggest users of launch >services and they demand top priority. This *is* a problem, but it's a problem with the launch sites, not the launchers. The commercial launch suppliers are quite interested in the various proposals for commercial spaceports, although it will be a while before anything major happens at the current rate. -- C++ is the best example of second-system| Henry Spencer @ U of Toronto Zoology effect since OS/360. | henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: Sun, 7 Mar 1993 03:04:31 GMT From: "Allen W. Sherzer" Subject: Shuttle budget Newsgroups: sci.space In article neff@iaiowa.physics.uiowa.edu (John S. Neff) writes: >The launches are from facilities owned by the government and are supervised You mean like all the airports in the country? That doesn't seem to be a problem for private airliners. >If there is to be a purely commercial launch service there has to be >sufficient commecial business for it to exist. Do you realize that there IS a commercial launch industry in the US? >Why should the government >use a commecial launch service when they have their own? Because a commercial launch costs about half what a government launch does. Allen -- +---------------------------------------------------------------------------+ | Allen W. Sherzer | "A great man is one who does nothing but leaves | | aws@iti.org | nothing undone" | +----------------------101 DAYS TO FIRST FLIGHT OF DCX----------------------+ ------------------------------ Date: Sun, 7 Mar 1993 03:44:34 GMT From: Dave Tholen Subject: space news from Jan 11 AW&ST Newsgroups: sci.space Henry Spencer writes: > Analysis of data from the Gaspra flyby turns up evidence of a fairly > strong magnetic field, suggesting that Gaspra's core is probably > nickel-iron, a bit of a surprise in what looked like a stony asteroid. Not so surprising given the result we published in The Astronomical Journal, volume 102, page 1509, from which I quote: "...Gaspra originated in the lower mantle, perhaps very near the metallic core, of a differentiated asteroid." This paper was published in 1991, before any of the Galileo data had been played back, and was based on ground-based visible and infrared spectrophotometry. Although Gaspra is an S type, the S class spans a huge range of colors, and presumably compositions. We identified Gaspra as one of the more metal rich S types, so a meteoritic analog would be the stony-irons. ------------------------------ Date: Sun, 7 Mar 1993 00:06:58 GMT From: 8 February 1993 Subject: The courage of anonymity Newsgroups: news.admin.policy,alt.privacy,comp.org.eff.talk,sci.space It's been six weeks now since I posted the original "Challenger" article to sci.space and sci.astro as a contribution to the on-going thread reminiscing on the tragedy. I am still surprised at the intensity of negative reaction that several posters had to the article and by association to the concept of anonymous posting. While the usual reader of those newsgroups may be far more comfortable with the inhuman aspects of space flight -- metric tons of fuel, pseudoinverse trajectory calculation, torrs of Oxygen, kilos of payload -- I believe that the phenomenon of crewed space flight is far more interesting at the sharp human edge, the sharp edge that cuts a thin bead of blood into the skin. Looking at political issues of funding and priorities as well as the social consequences of space exploration, many of us believe that the human angle is far more important, but fluid and ill-defined, than the technical problems of space travel. This protean quality of the human issue makes for many of us a more interesting challenge to understand and integrate into the whole picture than the relatively more deterministic mechanical issues. Sci.space and sci.astro need many more blunt posts centered on the human theme, even if strong medicine to many readers. As far as anonymous postings in general, the threats of personal violence that the Challenger post unearthed, for me, more than confirmed my decision to use it. The contrary arguments that legitimate science will be swamped with anonymous bacchanals is simply not happening, even though over 20,000 people now have used the Finnish anon service. The newsgroups have approximately the same mix of surplusage, truth and tripe as they always have had. The imminent death of the sci. and comp. groups seems a bit presumptuous. I think it takes far more courage to post anonymously than to hide behind your affiliations. For me, a poster who, although anonymously, slowly built a strong argument through a series of well-written anonymous posts and politely responded to counterexamples and the other stuff of a good debate, would capture my respect far more than Dick Reputable, Ph.D.@bigfoo.com making a simple pronouncement on the whole matter that his net-flacks are expected to parrot. Yes, it takes more effort to get your mind around anonymous posts than attributed ones: we get out of the habit of evaluating arguments without the guiding badges and trappings of authority accompanying them. Those posters who have forgotten how to legitimately persuade and, through time and accreting rank, have relied upon the prestige of their posting site may well have reason to fear the new order of things. But the content of the argument ought to be important for all posters, not just the ones who do not have a Keogh plan or a doctorate. Certainly most scientists agree that the necessity of experimentation, systematic observation, and falsifiability supporting a scientific truth applies equally to the member of the Academy as well as the first-year lab assistant. The concept of anonymous posting is the next great step in washing away the detritus that impedes our search for truths. Yes, it has a great capacity to annoy and anger, but it has an even greater capacity to engage the truth for those with courage enough to learn to use it universally and well. ------------------------------------------------------------------------- To find out more about the anon service, send mail to help@anon.penet.fi. Due to the double-blind system, any replies to this message will be anonymized, and an anonymous id will be allocated automatically. You have been warned. Please report any problems, inappropriate use etc. to admin@anon.penet.fi. *IMPORTANT server security update*, mail to update@anon.penet.fi for details. ------------------------------ Date: Sun, 7 Mar 1993 01:10:32 GMT From: Henry Spencer Subject: The courage of anonymity Newsgroups: news.admin.policy,alt.privacy,comp.org.eff.talk,sci.space In article <1993Mar7.004339.4397@fuug.fi> an8785@anon.penet.fi writes: >It's been six weeks now since I posted the original >"Challenger" article to sci.space and sci.astro as a >contribution to the on-going thread reminiscing on the >tragedy. I am still surprised at the intensity of negative >reaction that several posters had to the article and >by association to the concept of anonymous posting. Careful here. Some of us see nothing much wrong with the concept of anonymous posting, but think your article was trash. Why are you bothering with anonymous posting for such garbage? If you were, say, a NASA employee using the anonymity to spill the beans on something important, that would be different... but you hardly need anonymity to just repeat an old story from the supermarket tabloids. Come back with something that is more interesting and better substantiated and nobody (well, almost nobody) will object to the anonymous posting. -- C++ is the best example of second-system| Henry Spencer @ U of Toronto Zoology effect since OS/360. | henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: 7 Mar 93 02:32:20 GMT From: Tom Mandel Subject: The courage of anonymity Newsgroups: news.admin.policy,alt.privacy,comp.org.eff.talk,sci.space In article <1993Mar7.004339.4397@fuug.fi> an8785@anon.penet.fi writes: > > >I think it takes far more courage to post anonymously than to >hide behind your affiliations. I think you, sir or madam or whatever you are, are full of it. Anonymity is the veil behind which people too cowardly to identify themselves with their analyses or opinions hide. -- Tom Mandel mandel@netcom.com mandel@unix.sri.com [1] Opinions are mine, not my employer's, except when we agree. [2] Cyperpathologic personality disorder is not yet a job disability. [3] Email to the above; flames to alt.fan.amy-fisher. ------------------------------ Date: Sun, 7 Mar 1993 04:22:01 GMT From: Jim Thomas Subject: The courage of anonymity Newsgroups: news.admin.policy,alt.privacy,comp.org.eff.talk,sci.space mandel@netcom.com (Tom Mandel) writes: >In article <1993Mar7.004339.4397@fuug.fi> an8785@anon.penet.fi writes: >> >> >>I think it takes far more courage to post anonymously than to >>hide behind your affiliations. >I think you, sir or madam or whatever you are, are full of it. >Anonymity is the veil behind which people too cowardly to identify >themselves with their analyses or opinions hide. Although revelation is generally preferable to anonymity, there are numerous reasons that are sufficiently strong to discredit the "cowardice" thesis. Jim Thomas ------------------------------ Date: 7 Mar 1993 04:45:40 GMT From: Ted C Belding Subject: The courage of anonymity Newsgroups: news.admin.policy,alt.privacy,comp.org.eff.talk,sci.space Anonymous posting might have some virtues if it weren't used to post 73 lines of gibberish. -Ted Belding Zonker Harris Student of Computer Engineering, University of Michigan e-mail: streak@engin.umich.edu or Ted.Belding@um.cc.umich.edu 415 Lawrence, Apt. 2, Ann Arbor, MI 48104 USA Phone: +1 313 994 9573 ------------------------------ Date: 7 Mar 93 03:15:56 GMT From: Ed Hall Subject: The courage of anonymity Newsgroups: news.admin.policy,alt.privacy,comp.org.eff.talk,sci.space In article <1993Mar7.004339.4397@fuug.fi> an8785@anon.penet.fi writes: > >I think it takes far more courage to post anonymously than to >hide behind your affiliations. This is supposed to make some kind of sense? Sounds like an Orwellian re-definition of the words "courage" and "hide." It takes more courage to identify yourself than to hide behind your anonymity. There may be times when it is foolish to be so courageous, but you've made no claims which would justify your anonymity (like being a NASA employee or otherwise subject to genuine retribution if your identity is known). You've tried to bury your cowardice in a maze of words, but I doubt many people are fooled. -Ed Hall edhall@rand.org ------------------------------ Date: Sun, 7 Mar 1993 06:57:01 GMT From: Bruce Dunn Subject: The Planetary Society and Mars Exploration Newsgroups: sci.space I would be interested, if some serious effort were made to produce a report or some form of end product. I am personally most interested in what it would take to set up a permanent Martian colony. -- Bruce Dunn Vancouver, Canada Bruce_Dunn@mindlink.bc.ca ------------------------------ Date: Sun, 7 Mar 1993 07:32:16 GMT From: Nick Szabo Subject: Water resupply for SSF (?) Newsgroups: sci.space henry@zoo.toronto.edu (Henry Spencer) writes: >The deployment phase is the single diciest part of a sail design... Nevertheless, you think a small group of volunteers can pull it off, no? I'm arguing the Russians can pull it off, a small group of highly paid commercial professionals can pull it off, etc. Mirror deployment isn't anywhere close to being a show-stopper that would cause us to throw up our hands and say, "we need astronauts!", as Gary implied. >[Rosetta']s been considered worth a try, as a high-risk >high-payoff mission, since the mid-1980s. As I recall, problems like >preservation of the samples during return were considered minor ones >compared to the difficulties and uncertainties of the comet-surface >operations. The uncertainties are similar for both Rosetta and comet mining, regardless of material volume. These uncertainties weren't anywhere close to being a show-stopper. The probe sends back detailed pix for over a month, so that the best site can be picked, and can relocate of the first landing site doesn't work. Rosetta-type missions develop this kind of technique reducing the risk of commercial mining R&D. I've describe a comet sample return mission, using a Discovery or Artemis bus that would make it far less expensive than the MMII-based Rosetta. Launching multiple sample missions reduce the risk, and the commercial mission is also designed to be redundant in all aspects: multiple launches, multiple comets, multiple extractors, multiple ice rockets. In some scenarios a 75% failure rate can still bring a profit, but I expect the actual reliability will be much higher with a commercial mission. -- Nick Szabo szabo@techboook.com ------------------------------ Date: 7 Mar 1993 01:25 CST From: wingo%cspara.decnet@Fedex.Msfc.Nasa.Gov Subject: Without a Plan Newsgroups: sci.space I liked your post Henry in response to the post by Ron about planning and the next step after step four that was laid out by Ron. In my opinion the space program has a fundamental problem that cannot be solved by Allen and I reaching for the jugular. The American space program today has no central, unifying sense of purpose. There is a biblical quote that where there is no vision, the people perish. Well that word translated vision, means sense of purpose. NASA is drifting because America is drifting. NASA has no true sense of purpose in the strategic sense because the same is true of our nation. We are bogged down in minutae and detail. We fight about tactics when our strategy is going to hell in a hand basket. The space program today in the strategic sense is the victim of its past success. Born as a dream before the word cold war existed, it became a prostitute to those politicians who used it as a platform for political power. Like a beautiful virgin who has been seduced by a scoundrel, the space program has been tossed aside by those who rode her to power in the 60's. It is time for us to shake off the public relations symbology that our quest into space became victim of and begin again, this time beginning with the question; what is our purpose out there?; why do we want to go?; what good does it do for me or by brother? Beginning here we can build a strong, reasoned, responsible rational for both the American and the international space program. We need to go back to the dreams of Von Braun, Goddard, Oberth, and Ley. We need to go forward and look to the future that might be in a Star Trek world. Think about it tonight. There is a way, there is a path, there is a reason for what we are doing, not merely to put bread on the table, but to open up finally the final frontier, not just for the elite few but for all mankind. Dennis, University of Alabama in Huntsville ------------------------------ galileo.cc.rochester.edu!rochester!cornell!batcomputer!rpi!news.ans.net! malgudi.oar.net!news.ysu.edu!psuvm!frmop11.cnusc.fr!trearn!trmetu!consult0 Newsgroups: sci.astro,sci.space Subject: A new cosmological model ? Message-Id: <1993Mar6.122536.2123@lub001.lamar.edu> From: "A.Cagri YUCEL" Date: 6 Mar 93 12:25:36 +1700 Lines: 20 Sender: news@CRABAPPLE.SRV.CS.CMU.EDU Source-Info: Sender is really isu@VACATION.VENARI.CS.CMU.EDU Last night, at TV news I heard about a new cosmological model including a secodary explosion after the big-bang... More info required. Please E-mail to CONSULT0@TRMETU.BITNET Message-ID: <93064.120251CONSULT0@TRMETU.BITNET> Date: 6 Mar 93 02:01:24 GMT Organization: Middle East Technical University - Computer Center Lines: 10 Subject: A new cosmological model ? Last night, at TV news I heard about a new cosmological model including a secodary explosion after the big-bang... More info required. Please E-mail to CONSULT0@TRMETU.BITNET Thanks in advence. A.Cagri YUCEL ------------------------------ End of Space Digest Volume 16 : Issue 285 ------------------------------