Date: Sun, 13 Sep 92 05:06:51 From: Space Digest maintainer Reply-To: Space-request@isu.isunet.edu Subject: Space Digest V15 #196 To: Space Digest Readers Precedence: bulk Space Digest Sun, 13 Sep 92 Volume 15 : Issue 196 Today's Topics: Bioeffects of magnetic field deprivation Leftover Martians PHONE CELL SATELLITES 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: 13 Sep 92 06:39:06 GMT From: Jeff Bytof Subject: Bioeffects of magnetic field deprivation Newsgroups: sci.space Since the beginning of the year I've been looking into some rather astounding results offered by experimenters working in the area of the bioeffects of magnetic field deprivation. In view of the relevance to manned lunar and interplanetary exploration and biological research, I am posting the following information to sci.space and sci.bio. I. Quote from "Proceedings of the Sixth Annual Meeting of the Working Group on Extraterrestrial Resources", NASA SP-177 (1968), page 6: "The possible biological effects of the low lunar magnetic field are not known, but recent studies summarized by Busby indicate that they may be significant. In an experiment in which mice were raised in magnetically shielded cylinders, abnormal behavior, loss of hair, and early death were exhibited after the fourth generation..." II. Quote from "Biomagnetics: Considerations Relevant to Manned Space Flight", by Douglas E. Busby, M.D., NASA CR-889 (1967), pp. 10-12: "...During the past 18 months, these investigators [M.H. Halpern and J.H. Van Dyke] have kept Swiss/Webster white mice and their progeny in mu-metal cylinders 8 inches in internal diameter and 24 inches in length, oriented in the East-West direction. Mu-metal is an austentitic, nickel- iron-chromium-copper alloy of high magnetic permeability and low corrosion resistance. The magnetic field intensity in the cylinders apparently remained well below the 100 gamma level. Control mice have lived in similar aluminum cylinders, which do not have an appreciable attenuating effect on the Earth's magnetic field. The floors and end enclosures (inset one inch from the ends) of all cylinders consisted of non-magnetic, stainless steel, hardware cloth. The cylinders and cages were intermixed and adequate temperature, humidity and ventilation of them insured. The adult population of each cylinder was kept under 8 mice. "As pointed out in a preliminary, unpublished report, an unspecified number of originally four-month-old male and female mice were maintained continuously in mu-metal cylinders for periods of 4 to 12 months. Each shield originally contained a single mouse family of one male and three females (Group I). Data is not available on the number of mouse families this experiment was started with. First generation (F-1) mice litters were equally divided at weaning time (21 days), one-half (Group II) being retained in the mu-metal cylinders and the other half (Group III) being placed in the aluminum cylinders. Group I females were continuously re-mated with their original males. "In contrast to the normally-thriving control mice in the aluminum cylinders, the mice in the mu-metal cylinders have presented a characteristic, rather bizarre picture. Premature mating and frequent pregnancies have produced larger but apparently normal litters. By the F-4 generation, repro- duction has usually ceased. Unanticipated cannibalism and abortions of newborn mice has been encountered to a greater degree in the F-2 generation (and subsequent F-1 generations of the original animals) than in the F-3 and F-4 generations. At an early age, large numbers of mu-metal mice have become docile and inactive. Many mice have exhibited the highly unusual behavior of lying on their backs for prolonged periods of time. About 14 per cent of the adult population has developed a characteristic and progressive alopecia over the top of the head to at least half way down the back. Interestingly, there are no known mice which have the genetic trait of developing hair loss as adults. Coarse hair, characteristic of aged mice, has also appeared at an early age. Death has occurred prematurely, often as early as 6 months of age. "Histopathological observations have been made on selected organs from 36 Group I mice. Although the same manifestations were not always present in the same organs of all mice at the time of sacrifice, positive alterations, either grossly or microscopically, were apparent in most of the animals studied. Connective tissue and epithelial tumors, which have frequently been found in various loci, remain to be studied further microscopically. "The skin has been found to be hyperplastic, but only in areas of alopecia, and characteristically has an undisturbed basement membrane, excessive mitotic activity in the basal layer, columnar-shaped granulosa cells, a hyperkeratotic stratum corneum, and hair follicle plugging with hyper- plastic squamous epithelium. The livers of all experimental mice studied have shown the presence of hemosiderin crystals in the Kupfer cells to a variable degree. In addition, liver tissue from these animals has clearly exhibited nuclear changes characterized by increased numbers and noticeable enlargement of their nucleoli, suggesting perhaps some alteration in the metabolism of ribonucleoproteins. Periperal blood smears showed very noticeable deposits of hemosiderin within polymorphonuclear leucocytes, and a very high incidence of reticulocytosis. "Most kidneys studied were polycystic to some degree, the cysts often markedly compressing adjacent cortical parenchyma. Many experimental mice, especially those examined after spontaneous death, had their urinary bladders distended with urine and apparently a white precipitate. In at least a third of these mice, the bladder mucosa was markedly hyper- plastic, forming trabeculae and polypi. The combined findings of the polycystic kidneys and bladder precipitate suggested that certain of these animals might have succumbed from uremic poisoning. Notably, no bladder parasites have been found in either the experimental or the control mice. "The ovaries had numerous large, persisting corpus lutea, which often entirely encapsulated this organ. Few follicles were in evidence, in spite of the high incidence of pregnancy in these animals. In many mice, the uterus has been somewhat enlarged having numerous epithelial cyst formations in the endometrium. "Van Dyke and Halpern have pointed out that what they are observing in the mu-metal mice is a diffuse, hyperplastic condition. They cannot foresee any possible cause of this condition other than the chronic exposure to the extremely low-intensity magnetic field. It is suggested that a detailed evaluation of the protocols and conditions of this experiment should be made for the possibility of infectious, genetic or other factors being responsible for these unusual results. At present [1967], none of these protocols have been made available to other investigators or this reviewer." III. In January, I contacted Dr. Myron Halpern, now retired. I questioned him about his experimental results. I asked him about the possibility of mu-metal poisoning, which he held to be very unlikely. The experiments ended in the late sixties when funding ceased. The Apollo project was apparently satisfied that there were no problems with short-term (two week) exposure to low magnetic field strengths. Halpern was adamant that his work had brought up many questions that remained unanswered and was anxious to see others do additional experiments to check his results and to determine the mechanisms by which the absence of a magnetic field would affect organisms. Halpern still retains his mu-metal cylinders. IV. I next contacted researchers in NASA's Life Sciences Division at Ames Research Center. One recalled an early short-term experiment with low magnetic fields, but there are no experiments ongoing or planned within NASA. V. A literature search came up with this title: "Magnetic Shielding Induces Early Developmental Abnormalities in the Newt, Cynops pyrrhogaster", M. Asashima, K. Shimada, and C. Pfeiffer (Bioelectromagnetics 12:215-224 (1991)). Quote of the abstract: "Developing larvae of the Japanese newt, Cynops pyrrhogaster, were subjected for 5 days to a shielded environment in which the static magnetic field was about 10,000 times weaker (5 nT) than the geomagnetic norm, which ranges between 30 and 60 micro Teslas at the earth's surface. Larvae from non-cleavage to neurula stages were exposed under shielded or normal (control) conditions and then examined for evidence of developmental abnormalities either 1 day or 20 days after treatment. The magnetic shielding was associated with an increased incidence of somatic defects, especially in larvae that were examined 20 days after shielding. Bi-headedness and intestinal protrusion were observed in magnetically shielded larvae but not in controls. Other abnormalities more frequently observed in shielded larvae were spinal curvature, malformed eyes, and retarded or blocked development. These data are among the first to illustrate the effects of magnetic-field deprivation on a developing animal." VI. I wrote a letter to Dr. Makoto Asashima, Dept. of Biology, Yokohama University, one of the authors above. He replied, "I have a plan to conduct more extensive low magnetic shielded experiments." They have a much different method of producing low magnetic fields than Halpern and Van Dyke. They are using a magnetically shielded facility of the Japanese Institute of Space and Astronautical Science at Sagamihara. I believe Dr. Asashima also has some responsibility for life experiments on the current or a future shuttle flight. ---------------- Jeff Bytof rabjab@golem.ucsd.edu ------------------------------ Date: 13 Sep 92 07:27:14 GMT From: Nick Janow Subject: Leftover Martians Newsgroups: sci.space brad.thornborrow@rose.com (brad thornborrow) writes: > I havn't been following the entire conversation here, but it seems to me > everybody is missing the gravity problem. Last time I checked, Mars' gravity > was not strong enough to keep oxygen molecules from escaping into space over > time. So, even if one could start plant-life on Mars, you'd have to have a > heck of a lot of it to keep the oxygen from just "floating away"!!! The reference material I have says that Mars can lose oxygen through non-thermal means (such as splitting ozone), but it doesn't seem to indicate a very fast loss mechanism. The oxygen is replenished by the photodissociation of water and the loss of that hydrogen. Actually, life on Mars evolved to handle the loss of oxygen partial pressure. They grew silica terrariums enclosing photosynthetic material, air and water. During the day, it turns the CO2 into O2; at night or when covered by sand, it utilizes the stored O2. As the surface conditions worsened, the plants growing the tallest silica projections (light pipes) survived. Now, the bubble plants live deep beneath the surface, with roots that dig into the permafrost layer. Some plant colonies store the air in deep chambers, so that the loss of leaves (air bubbles) to sandstorms is not so critical. In fact, the loss of those air bubbles is their form of propagation; bubbles immediately start forming roots and fibres, hoping to form a link between water ice and light before their reserves run out. Now, what about predators... :-) -- Nick_Janow@mindlink.bc.ca ------------------------------ From: Nick Szabo Subject: PHONE CELL SATELLITES Newsgroups: sci.space Message-Id: <1992Sep13.063015.19520@techbook.com> Date: 13 Sep 92 06:30:15 GMT Article-I.D.: techbook.1992Sep13.063015.19520 Organization: TECHbooks --- Public Access UNIX --- (503) 220-0636 Lines: 149 Sender: news@CRABAPPLE.SRV.CS.CMU.EDU Source-Info: Sender is really isu@VACATION.VENARI.CS.CMU.EDU PHONE CELL SATELLITES Current cellular phones use a network of thousands of ground-based towers each projecting a radio "cell" a few miles across. Service is largely limited to cities in developed countries. Phone cells can greatly expand this service, while developing the critical technology of miniature spacecraft components for the 21st century. The biggest markets are travellers and wealthy third worlders, who number 10's of millions despite being a small % of the total -- in Russia, India, China, Brazil, Mexico, Iran, Indonesia, Thailand, Turkey, Eastern Europe, etc. that have no cellular service. Cellsats can also usefully serve international air and ocean lines. At least initially, it won't compete with existing cellular service. The market is universally (well, globally :-) available cellular service, at a higher cost. How much higher depending on how many people sign on...the old chicken & egg story. If everybody signed on, it would actually be much cheaper than the current local cell system, but these companies do not count on that to happen initially; the systems can pay for themselves by opening new niches. The cost of the most publicized system, Iridium, is projected at $3 billion. If one out of every five thousand people on our planet make $300 worth of phone calls a year for ten years, the system pays for itself. Initially this would be mostly business, not personal use (as was the case for city cellular when it started out). For this market the price will be about twice as high as the current city cellular. If the market expands well beyond 1/5,000 of the world population, the price can go below that of current urban markets, supplanting the thousands of towers with a more efficient set of radio cells projected from space. Concievably, with an expanded set of satellites the price of cellular service could drop well below the price of current international long distance, replacing GEO satcoms altogether for this $10 billion/year market. Initially, the technology will be quite properly marketed at the 90% of the Earth's surface currently without cellular service. IRIDIUM Here are the Iridium specs. Note that the constellation has been redesigned for larger satellite and cell size, reducing the number of satellites from 77 to 66: satellite: 386 kg user handset: 3 lbs voice,data,fax digital & encryptable global digital switch network markets: - general aviation and business aircraft - maritime communications - rural, Eastern Europe & Third World locations $3/minute - 1/2 to local providers - 1/2 to Iridium members 370 mi. dia. cell * 37 * 11 * 7 (100K mi.^2) 66*4 cross-link antenae, each 20 Ghz adjacent planes move in opposite directions Some tasks the Iridium people are working on: * Building the satellites. Since the scale is small, new technology can be incorporated and tested with small risk. Thus, there is no need to stick with old electronic technology used in the larger GEO satcoms. Lockheed will be in charge of developing the satellite bus and choosing the launcher. Motorola will develop the communications payload and make and market the cellular phones. * Choosing a launcher capable of boosting test and replacement satellites into their unique orbits for less than $10 million, as well as a launcher for the main satellites, from one to seven at a time, for less than $8 million apiece. Currently Pegasus costs $10 million and fits the first bill, although with only one good launch under its belt it needs to prove its reliability. Delta or Atlas launching Iridium in groups of 6 could fit the second bill, and a rumored Russian competitor to Pegasus might be able to launch singlets for less than $8 million. OSC needs to finish the Pegasus' hydrazine stage to improve the orbital insertion accuracy. The development of Pegasus' low entry-level-cost capability was a main driver behind the inspiration and genesis of Iridium and several other emerging small satellite industries. * The Iridium Consortium must obtain a set of frequencies in all the countries in which it wants to market its service. Phone cell satellites have obtained frequency from WARC and now each proposal must compete at national government levels. * New members must be added to the Iridium consortium; Motorola and Lockheed probably won't pay all the $3 billion on their own. The finance folks are busy talking to people like AT&T, NTT, and dozens of other deep pockets. Whoever puts in the most money could very well gain control over the world's cellular phone industry. GLOBALSTAR This information is from Klein Gilhousen of Quallcomm, Inc., which is teamed with Loral and several European companies on Globalstar: There will be 24 satellites in LEO (750 nm) in the initial deployment with coverage optimized for the U.S. Later, when international agreements are in place, the constellation will be expanded to 48 satellites, providing global coverage and improved coverage and capacity over the U.S. The system uses NO intersatellite relays. (I believe that these relays are a prime cost driver of the Motorola approach and that they would solve a non-existent problem. The problem is to connect mobile users into the network. Period. Global routing of phone calls is something that we already have.) By virtue of have no crosslinks, the satellite is significantly smaller and cheaper than the Iridium system. Total launch mass of one satellite is 262 kg. Eight satellites would be stacked and launched at once by a Delta, Ariane, or other standard launch vehicle. Airtime charges are projected to be in the same range as cellular service. According to the filing, initially, the airtime would be $0.31/minute with a monthly access fee of about $24. Later on, charges would fall to about $0.22/minute. The mobile phones will be based on CDMA digital cellular phones with RF adaptors to make them work in the L and S bands of the satellite system. Thus, the cost would be that of a CDMA cellular phone, plus maybe 10-20 percent for the adaptor. The system would offer call capacity comparable to that of the Iridium system's satellite network with many fewer and less costly satellites through the use of the CDMA technology. Because a much smaller investment is required, the service cost will be correspondingly smaller. CONCLUSION Thinking small -- thinking at the optimum economical scale of technology, instead of the idealistic scale of technology -- is one of the major paradigm advances of phone cell satellites. The Iridium and Globalstar breakthrough is a good example of why industry is needed to set the standards for space technology, instead of government dictating to industry. Private industry is far more in tune both with the advance of technology and the needs of people. Government civilian programs have practically ignored -- spent less than 1% of their budgets on -- the technology needed for this lucrative market. Private industry is putting up its own money to fill this gap. -- szabo@techbook.COM Tuesday, November third ## Libertarian $$ vote Tuesday ^^ Libertarian -- change ** choice && November 3rd @@Libertarian ------------------------------ End of Space Digest Volume 15 : Issue 196 ------------------------------