Date: Tue, 20 Oct 92 05:02:13 From: Space Digest maintainer Reply-To: Space-request@isu.isunet.edu Subject: Space Digest V15 #328 To: Space Digest Readers Precedence: bulk Space Digest Tue, 20 Oct 92 Volume 15 : Issue 328 Today's Topics: Dyson Spheres and Cosmic Spaghetti Earth's two moons Federation gives a decent explantion to you (2 msgs) Galileo's antenna (was Re: Gallileo's Jobs-Aerospace (2 msgs) More speculation about eavesdropping (was Re: HRMS/SETI Answers) V-2's launched at Russia Weather satellites & preventing property damage 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: 19 Oct 92 18:13:12 GMT From: Mark Frazier Subject: Dyson Spheres and Cosmic Spaghetti Newsgroups: sci.astro,sci.space asnd@erich.triumf.ca (Donald Arseneau) writes: : In article <1992Oct18.212301.1597@m.cs.uiuc.edu>, carroll@cs.uiuc.edu (Alan M. Carroll) writes... : : >Niven proposed a different form of this which was sort of neat. : >Instead of multiple O'Neil colonies, you just build one that's : >extensible. You extend it until it wraps all the way around. If it's : >thin enough (say, ~10km with a 1AU radius) the rotation stresses are : >negligible. So you can spin it for gravity. : : Nope. Niven had to invent yet-another-impossibly-strong-material : for his ringworld. Scrith, I think he called it. : : Oh! Re-reading, perhaps Alan means the ring is a torus, and spins around : its small circle. In that case the stresses *are* negligible, but it : wasn't Niven's ringworld. Then you should read "The Integral Trees", and "The Smoke Ring", by Niven, in which they do find a torus. BUt this is all irrelavent next to the fact that two weeks ago on Star Trek, they established that patterns in the pattern buffer couldn't exist for more than about 30 seconds without degrading too far, yet Scotty managed it for 75 years. That Scotty, still doing miracles! I was dissappointed at his admittance that he always exagerated completion times to look better when he finished...... :-) MMF ------------------------------ Date: 19 Oct 92 20:56:59 GMT From: Jr Childers Subject: Earth's two moons Newsgroups: sci.space In article cocking@csugrad.cs.vt.edu (Cara Cocking) writes: > > I took an astronomy class in high school and my teacher told us that > Earth really has two moons but that the other one can't be seen unaided > because it's a lot smaller and farther out. > > I've been telling some people that Earth has two moons but no one > believes me. Could someone please confirm this? Try this. Open your textbook ( or get one from a library ). Look up the earth's number of moons in the appendix. Then show it to your teacher and ask for an explaination. Have fun. John Childers UNCCharlotte john@opticslab1.uncc.edu ------------------------------ Date: 19 Oct 92 17:01:57 GMT From: asljl@acad2.alaska.edu Subject: Federation gives a decent explantion to you Newsgroups: sci.space,sci.skeptic,alt.alien.visitors For all of you who have been waiting for a decent explanation of the drive/laser system, from the Federation, Here you are: Lady Rhavyn Asljl@acad2.alaska.edu, questions, ideas comments ? 1 Federation Science Academy; Engineering Research Text A FEDERATION RESEARCH PROPOSAL: By the synthesis of several fields of scientific and engineering specialty, the production of a new form of space drive may be possible. This new drive will represent a literal quantum leap in space propulsion technology, entailing as if does the reduction of space drive components to a single 51 centimeter crystal. This generator uses a block of semi-conductor material as light-amplifying material, also called an Injection Laser. A common material used is Gallium Arsenide. The Semi-Conductor material consist of two layers that differ electrically. Electron current passes through the semi-conductor generates laser light along the junction between the two layers. The device, a quantum well diode laser, is made of a layered alloy of gallium-aluminum-arsenide. The middle layer, which is the active layer, is made of nearly pure gallium arsenide, and is only six-millionth of a millimeter thick. The two layers on either side of it are 10 times as thick and contain 30 times the atoms of aluminum for every 70 atoms of gallium. These layers are in turn sandwiched between two still thicker outer layers, containing 25 atoms of aluminum for every 75 atoms of gallium. The entire device is about 0.25 millimeters ( 0.01 inch ) square and one thousandth of a milli-meter thick. When a voltage is applied and current flows, this radiative recombination has to be confined along the junction plane and must be reflected by a parallel, partially reflective surface so as to form a cavity. These parallel mirrors are readily obtained by cleaving along the natural cleavage planes of the III - V compound semi-conductors. The injection electrons and the light must be confined to the same region so that they can interact to enhance the stimulated emission. To provide the carrier and light confinement to the region of the p-n junction and obtain continuous operation at room temperature, it is necessary to use a heterojunction - i.e., the junction in a single crystal between two dissimilar semi-conductors. The most significant difference is the energy gap and the refractive index. A double hetero-structure made with aluminum gallium arsenide ( Al-Ga-As ) and pure gallium arsenide and indium phosphate gallium indium are now being used. Al-Ga-As is used to jacket, or clad the pure Ga-As core which has a smaller energy gap than the two cladding layers. Typical values for X in the formula Al = x : Ga = -x : As, is x = 0.3. This gallium Arsenide region with a smaller energy gap is where the light with a smaller energy gap is generated due to radiative recombination of the injected carriers; it is called the active region. Other pairs of semi-conductors may be used, but all require a smaller-energy-gap active region with larger-energy-gap cladding layers. Also to prevent non-radiative recombination at the heterojunction interphases, the active layer and the cladding layers must have the same lattice constant. Electrical current travels through the layers in the form of moving negatively charged electrons and positively charged holes - These are empty spaces around atoms in materials crystal structure where electrons normally are situated. Under the influence of an electric field, an electron can jump from one hole to another. The hole the electron left behind can in turn be filled by a neighboring electron, which leaves another hole. As this process repeats itself, a hole in effect " travels " through the crystal. The middle layer acts as a pit, called a quantum well, which the electrons either overshoot or fall into. When an electron falls into a hole, the electron gives up energy in the form of a photon - a bundle, or quantum or light. A photon vibrates with a frequency equal to its energy divided by a number called Planck's constant. According to the laws of quantum mechanics that govern the emission of photons, electrons in an object can emit photons that have only certain special amounts of energy. Furthermore the number of possible amounts of energy, and the amounts themselves, given up by electrons as they fall into an object depend upon the size of the object. The smaller the size the object, the smaller the number of possible energies. Because the laser's middle layer is extremely small, when an electrical current flows across the laser, the middle layer emits photons, each of which has the same energy and frequency, corresponding to light of a deep red color. The basic principle of the laser is that photons of this frequency encourage electrons in the gallium arsenide to fall into the holes, emitting still more photons of the same frequency. As a result, it is possible for a weak current to cause the middle layer to emit tremendous numbers of photons with a single frequency. When the current rises above about 0.3 ampere, the device begins to emit laser light. The light output increases with further increases in the current. Only 1.5 amperes will produce 1/2 watt of light. The fundamental idea of this C.I.E. generator is that of the injection laser. However, that is merely the first stage. In the second stage the use of super conducting material and quasicrystals enhance and increase the injection lasers efficiency to provide adequate energy-to-thrust ratio for forward motion. The semiconducting material is matrixed in a super conducting lattice at an atomic level. Replacing the Oxygen-Copper pairings with Al-Ga-As. A superconductor conducts or carries electric current ( a flow of electrons ) without resistance. In may 1987, some evidence of superconductivity in a complex substance apparently occurred in microscopic " sandwiches " made up of insulated material located between layers of a superconductor. This is the same formation as that of a semiconductor. The new superconductors are ceramics - material that are neither metals nor plastics. The super conductors are brittle and are difficult to make into films or wires suitable for technical applications because its strength is proportional to the size of the crystalline grains in the superconductor. When researchers tried to increase grain size, their brittle materials cracked. Then silver, which absorbs strain but doesn't interfere with superconductivity was included in the formula of yttrium, barium, copper, and oxygen. Including the silver produced large grain superconductors, allowing a 4.5 pound tank of water, holding a living goldfish, to be levitated atop a ring magnet. The copper and oxygen atoms in these materials are staked in flat layers ( known as planes in geometry ). In each " building block " of the crystal lattice, copper an oxygen form one or more layers, while the other elements make up the remainder of the block. The blocks are stacked one upon another like a deck of cards to fill out the crystal. The critical temperature seems to depend upon the number of copper-and-oxygen layers per block - the more of these layers , the higher the critical temperature. The material with a critical temperature of -148 degrees C has three consecutive layers made of copper and oxygen and atoms in each block. In 1980, they imposed a strong magnetic field perpendicular to a very thin conducting layer in an electronic device known as a semiconductor-insulator junction. This caused a current to flow through the layer. Surprisingly, they found that the strength of the resulting electrical field was no longer simply proportional to the magnetic field and current, but increased by quanta, or steps, as the magnetic field increased. Successive steps did not depend on the nature of the specific conducting material. Rather, the steps were always at an exact or whole-number multiple of the current times the square of the charge of electrons divided by Planck's constant. The presence of moving magnetic fields can be shown by the Meissner effect, the rejection of a magnetic field by a superconductor that's cooled below critical temperature. Magnetic Field; a Region in the neighborhood of a magnet, electric current or changing electric field in which magnetic forces are observable. Magnetic fields force moving electrical charged particles in a circular or helical path. The magnetic force on a moving charge is exerted in a direction at a right angle to the plane formed by the direction of its velocity and the direction of the surrounding magnetic field. The Meissner effect occurs because the magnetic field of the permanent magnet causes super conducting currents to flow on the surface of the pellet. These currents produce a magnetic field in the direction opposite of that of the permanent magnet's field. The portion of the superconductor's field inside the superconductor has exactly the same strength as the portion of the magnet's field extending inside the superconductor. So the magnet's internal field is canceled out. But the magnet's external field exerts a repelling force on the super conducting current carriers ( electrons or holes ) flowing on the surface of the pellet, causing the pellet to remain suspended. When a magnetic material is cooled in an outside magnetic field of constant direction, the small regions quickly grow into large domains in which the atomic magnets are aligned with the outside field. Scientist have found that certain impurities in the crystal structure of magnetic materials make boundary motion more difficult. The field inside a type II material became concentrated in various positions that depend upon the crystal structure of the particular superconductor. Certain irregularities in the shape of the superconductors crystal structure and certain impurities ( atoms that normally are not present in the materials ) can " pin down " these field concentrations. In a metal of alloy type II superconductor, movement of these magnetic field concentrations - know as fluxcreep - creates some electrical resistance, but not enough to prevent these materials from being useful for a variety of super conducting applications. As the temperature increases, atoms in the super conducting material vibrate more and more rapidly, increasing flux creep. The moving field concentrations interfere with electrons or holes forming the super conducting current, thereby raising resistance. That flux creep can be exceptionally strong in ceramic superconductors that are made up of the chemical elements yttrium, barium, copper, and oxygen. The amount of current that can pass through a high-temperature superconductor is limited by the behavior of a three-dimensional magnetic structure called a flux lattice. When a ceramic superconductor is placed in a magnetic field, the field forms intermeshing, string-like concentrations of magnetism called fluxiods. An electric current can move fluxiods about and thus transfer some of the current's energy to the superconductor. This causes the superconductor to lose its zero electrical resistance. The higher the temperature at which the superconductor operates, the looser the lattice becomes, and so the easier it becomes for current to move fluxiods about - increasing the material's resistance. To prevent lattices from loosening researchers took advantage of a characteristic of certain conventional superconductors. In those materials, fluxoids can be immobilized, or " pinned down, " by defects in the crystal of the material. The current density of the altered crystalline material was about 10 times that of the material without the defects ( Current density is the amount of current flowing through a given cross-sectional area of a material.). A technique for altering the crystal structure of a high temperature superconductor by introducing crystal defects. The researchers measured the density of a current flowing through a crystal made up of yttrium, barium, copper, and oxygen. Then they bombarded the crystal with neutrons, creating defects every much like cracks in a brick wall. When they again passed a current through the crystal, the fluxiods stuck to the defects and did not interfere with the currents. As a result, the current density increased sharply to an amount that would make these materials useful for magnets. Another way of dealing with this problem would be the use of quasicrystals. A quasicrystal is a material which solidified into a crystal like object with a unit cell that could not possibly repeat itself in a periodic fashion. Researchers wondered how the object which came to be known as a quasi-crystal, could exist. The explanation came from an unexpected source. In the mid-1970's, theoretical physicist Roger Penrose developed a geometric structure comparable to sets of tiles of two different shapes that cover a floor in only non-periodic arrangements - that is, without regular distances between identical tiles pointed in the same direction. Penrose's discovery in plane geometry could be applied to solid geometry. Unit cells in the shape of an iconahedron ( a solid with 20 triangular faces ) could combine non-periodically to form a quasi-crystal. The ordering of the unit cells would be quasi-periodical - that is, distances between unit cells oriented in the same direction would repeat in a pattern, but not a periodic pattern. Instead the distances would change according to the Fibonacci sequence ( the continuous series of numbers beginning 1,1,2,3,5, in which the first two numbers is the sum of the preceding two numbers ). In October 1985, five researchers obtained quasi-crystals by bombarding a thin film of aluminum and manganese with a beam of xenon ions ( charged atoms ). The bombardment with ions rearranged atoms in the alloy to form a quasi-crystal. From the previous information is possible to formulate a synthesis of the various sciences described. A layered super conducting matrix of injection laser material Al-Ga-As, is laid down on normal semiconducting state. Then a quasicrystal superconductor, is overlaid as an insulating layer and heterojunctioned to the plane of the Al-Ga-As, forming the quantum well where the electron-photon conversion takes place. By using the quasicrystal structure to pin down the magnetic fields, massive electric fields will be generated at right angles to the original electron current path. These electric fields will act to " push " the electrons in the alternative junctions. In turn these electron currents will produce massive electric fields in the original current pathways. This double-push effect will increase electron-photon conversion. Throughout the more than 50 years of the particle-accelerator history, the strong electric fields that " push " the particles have always been provided by powerful radio waves, far stronger electric fields are present in the light waves produced by lasers, however. A light beam, like a radio beam consist of an electric field and a magnetic field. Strong electric fields are also found in plasmas - gases made up of atomic nuclei and independent electrons. Experiments beginning in 1983 focused intense flashes of laser light on an are of less than 1 square millimeter ( 0.0015 square inch ). Each flash lasted only ten-trillionth of a second, but for that instant the flash maintained electric fields thousands of times more powerful than those commonly used in particle accelerators. Fields this strong generate forces as powerful as those that hold atoms together. They can play havoc with any atoms that falls within their grip. Energy flows rapidly into the atoms, causing it to spew forth electrons. In a single laser flash, an atom may absorb as many as 100 photons and eject as many as ten electrons. Ordinarily, an atom absorbs one at a time and it is extremely difficult to remove several electrons from one atom in a single step. By this method, the quantum effect of electron-photon conversion is amplified, producing a sub-quantum field transfer effect of near 70-to-80% efficiency. By exponential expansion, the crystal electric-magnetic fields should reach a strong-force counter reaction by the time the electron-current flow has reached the end of the crystal. The end product of this action should be an quanta level release burst of energy along most known frequencies of the electromagnetic wave-band. ( Harnessed nuclear thrust.) The manufacturing of a new, ultra efficient space drive for the twenty first century is fundamentally within the technological capabilities of todayUs industrialized nations. The manufacturing equipment is already in place. Most of the engineering is on-shelf. The only problems will be the combination of these technologies to create the desired product. Much like EdisonUs inventions involved little to no new technology or resources. This device is readily manufacturable with little to no new Scientific or Engineering art. What is needed for the development and creation of just such a space drive is the following: 1.) A semi-conductor Processing/manufacturing lab. 2.) A set of matched, electro-para-magnetic bottles. 3.) Ultra sonic containment and oscillation equipment. 4.) Heating and cooling elements with a +/- 1700 range 5.) computer/robotics equipment. To manufacture the Drive crystal, a Semi-conducting manufacturing chamber must be first modified to handle several other operations. First, a ceramic interior shielding must be added to allow the chamber to reach upward of 1700 degree Fahrenheit temperatures. Second, ultra-sonic containment equipment must be installed on the spraying platform. The sound beams must have a fifty percent overlap capacity, with a coverage of the entire area to be effected. Third, super-conducting electro-magnets with a hundred percent overlap and matched magnetic domains must be installed around the spray area. Ultra sonic fields must be set up to insure no substance adheres tot he magnetos and corrupts the field lines. Third, the chamber has to be made air and vacuum tight. This will mean the inclusion of computer controlled robot arms. Two sets per-wall with a duo set of television and spectrographic laser analyzers on at least one. With this set up in place the manufacturing is ready to take place. First, establish as single, harmonious magnetic field around the work area. This will act as the aligning field for the magnetic domains forming in the drive crystal. This in effect will produce a single magnetic spin direction in the whole unit. After this is completed, the next phase is to introduce a fifty two ( 52 ) centimeter piece of silicon into the chamber. This is then placed in the work area. The surface of the strip is rough, so it's are polished with abrasive liquids. Then the strip is exposed to oxygen in an oven, causing a hard layer of silicon dioxide to form on the surface. Silicon dioxide is an insulator, a material that does not conduct electricity. Finally, the surface receives a coating of a light-sensitive chemical. A mask and strip are placed in a machine which shines a light through the stencil-like mask, imprinting an exact duplicate of the circuit patterns onto the strip's surface. This is used to create the current pathways which will be the fundamental focus of the driveUs operations. Next, chemical's etch ( eat away ) the unexposed portions of the strip surface, leaving a silicon dioxide replica of the desired circuit patterns. Other substances are then deposited on the strip in various ways. Maintaining the strong magnetic bottle, the ultra-sonic fields are now activated to insure that the elements settling onto the strip settle in a quasi-crystal formation. That is the unit cells would be quasi-periodical - distances between unit cells oriented in the same direction would repeat in a pattern, but not a periodic pattern. Instead the distances would change according to the Fibonacci sequence ( the continuous series of numbers beginning 1,1,2,3,5, in which the first two numbers is the sum of the preceding two numbers ). With this as a first stage, the oven is now re-pressurized, to 10,000 psi and a gas consisting of 2 percent Iron, 3 percent Bismuth, 4 percent Copper, and 5 percent Aluminum Oxide 5 percent Silver is pumped into the heated chamber. The composite gas enters the areas of exposed silicon and silicon dioxide and insert themselves into the silicon crystal, forming sectors that will act as circuit parts. The gas is allowed to form heavy, quasi crystals over the surface of the strip. Maintaining a constant temperature and pressure for 18 -to- 20 hours, the gas is continuously re-circulated into the chamber until it adheres to the wafer. After 20 hours, the temperature is slowly reduced, but the pressure remains constant. The new quasicrystal strip is allowed to slowly cool for the next 7 -to- 10 days. After which the process starts all over again. A new silicon strip with new circuit designs are placed in the oven, over the crystals, and then re-pressurized and heated. More composite gas is added, until both wafers are overgrown and joined together. Repeating such steps - Coating, mask flashing, etching, and diffusion - creates multiple layers. C.I.E. Drive Research Questions - 1.) If a conversion ratio of 1.5 Amperes produce 1/2 a watt of light ( 1.5a=1/2w ) in a device 0.25 millimeters long, what will the wattage output be at the end of a device 51 centimeters long? 2.) If an electric charge in motion creates a magnetic spin field, then the magnetic charge of a crystal-semiconductor laser of 51 centimeters might produce a magnetic field strengthening in density every half millimeter. What would the magnetic field strength be by 51 centimeters. 3.) Could increasing magnetic compression of the molecular structure create resonance waves in the lattice causing instability and collapse? 4.) Could the use of quasi-crystal tiling, anchor the magnetic spin charges and stabilize the magnetic compression problem? 5.) Could the use of quasi-crystal tiling be as atomic level switching nodes? 6.) If atomic level switching is possible, could the bi-level lattice structure be paralleled as a combined computer system and drive unit? ( Main junction planes used as drive pathways. Vertical/diagonal tiling junctions used as computer switching/feedback.) 7.) Combining semiconducting/piezoelectric lattice structures with super conducting/quasi-crystal ceramic tiling junctions in a north/front - south/back hyper-magnetic domain; what will be the effect on piezoelectric compression? 8.) Semiconductors use level 2,3,4,5, and 6 combined with columns 2, 3, 4, 5, and 6 would it be feasible to in-phase palladium for Yttrium in the super conducting matrix/Germanium in the semiconducting matrix, stabilizing the semiconducting lattice on an electron hole structure, allowing the excess electrons to be transferred to the hetero-junction planes, increasing the laser output? 9.) Experiments in 1981 proved that intense, coherent light flashes in an area of less then 1 millimeter lasted only ten-trillionth of a second produced electric fields thousands of times more powerful then those used in particle accelerators; Combined with the possible hyper-magnetic fields generated by electric fields in motion, what would the classification of the field generated after the process has reached the theoretical 51 centimeters? 10.) If the proposed primary purpose ( drive unit ) is proven faulty, can this design be a: A.) Optical computer B.) High energy laser weapon. C.) Electron laser D.) Ion generator E.) Magnetic resonator focus 11.) Supposing a combined synthesis is possible. What would possible side-effect energy fields might be observed? 12.) No weak-force activity has been observed in any of the separate component operations. Could this combined matrix generate weak-force radiation harmful to biological life? 13.) If weak-force is observed, what would the effects of the decay be on the internal structure. 14.) If this matrix can generate a strong field action, would it be possible to match resonating actions with a second matrix and construct a heterodyned field charge at a distance from the unit? ------------------------------ Date: Mon, 19 Oct 1992 22:09:14 GMT From: Robert McGrath Subject: Federation gives a decent explantion to you Newsgroups: sci.space,sci.skeptic,alt.alien.visitors In article <1992Oct19.130157.1@acad2.alaska.edu>, asljl@acad2.alaska.edu writes: |> For all of you who have been waiting for a decent explanation of the |> drive/laser system, from the Federation, Here you are: |> Lady Rhavyn Asljl@acad2.alaska.edu, questions, ideas comments ? |> 1 Federation Science Academy; |> Engineering Research Text Perhaps I missed something. Just what the heck is this all about? Who is "The Federation"? What is "the drive/laser system" and what is it for? -- Robert E. McGrath Urbana Illinois mcgrath@cs.uiuc.edu ------------------------------ Date: 19 Oct 92 18:48:37 GMT From: "Don M. Gibson" Subject: Galileo's antenna (was Re: Gallileo's Newsgroups: sci.space In article 7ut@zoo.toronto.edu, henry@zoo.toronto.edu (Henry Spencer) writes: >In article <1992Oct16.143422.6294@eng.umd.edu> sysmgr@king.eng.umd.edu writes: >>ASSUMING opening of the HGA, >>Would it be useful to use the HGA in combination with some of the on-the-fly >>"improvements" to pump back more data? I'd think of the options listed above, >>the data compression technique might be able to provide more data... > >I doubt that the onboard computers have the horsepower to do the data >compression at HGA speeds. I could be wrong. you wrong, not likely. in GLL AACS the CPU chugs at about 1MIPS. during science acquisition the CPU runs at at least 95% of capicity. (maintainance stuff runs in the idle time). That means that GLL has about 50KIPS to spare--at most! The top rate of telemetry (data) is 134Kbit/sec. Clearly, there is not enough CPU time to process in real-time. ------------------------------ Date: Mon, 19 Oct 1992 18:34:40 GMT From: kjenks@gothamcity.jsc.nasa.gov Subject: Jobs-Aerospace Newsgroups: sci.space In article <92289.130301WAF102@psuvm.psu.edu> William Fabanich writes: >Anyone have an approx. number for the number of people employed by gov >and industry who do any related work with the space program ? I've never seen an estimate, but I can back one out of the budget figures. Assume that 85% of the budget is salaries and 15% hardware. I believe that current US space expenditures are $35 B (correct me if I'm wrong). We usually assume $100 K per person for salary, benefits and overhead (which just goes to pay somebody else's salary, benefits and overhead, but we'll ignore that). So 0.85 * 35x10^6 / 100x10^3 = 297,500 people. Call it 300,000. -- Ken Jenks, NASA/JSC/GM2, Space Shuttle Program Office kjenks@gothamcity.jsc.nasa.gov (713) 483-4368 "Is there life on Mars? Maybe not now. But there will be." -- Daniel S. Goldin, NASA Administrator, 24 August 1992 ------------------------------ Date: 19 Oct 92 19:44:22 GMT From: Andy Cohen Subject: Jobs-Aerospace Newsgroups: sci.space In article <92289.130301WAF102@psuvm.psu.edu>, William Fabanich wrote: > > Anyone have an approx. number for the number of people employed by gov and indu > stry who do any related work with the space program ? Last I heard....SSFP kept at least 400,000 people at NASA, prime contractors, subcontractors, vendors, at other misc jobs....employed..... Yes sir, a real WPA! ------------------------------ Date: 19 Oct 92 22:01:51 GMT From: Antti Karttunen Subject: More speculation about eavesdropping (was Re: HRMS/SETI Answers) Newsgroups: sci.space,sci.astro In article <1992Oct12.164115.15135@ousrvr.oulu.fi> dah@tko.vtt.fi (David Harwood) writes: >In article <1992Oct9.145536.19786@elroy.jpl.nasa.gov> eto@elroy.jpl.nasa.gov (Edward T. Olsen) writes: >[...] >>Neither component is capable of detecting the leakage of our >>commercial broadcasts at interstellar distances. However, there have >>been highly beamed, strong signals emitted from the Earth which both >>components are capable of detecting. The strongest signal emitted from >>the Earth is the Arecibo planetary radar, EIRP = 10**13 W. The strongest >>commercial broadcasts eminate from UHF television stations, and have >>EIRP = 10**6 W to 10**7 W. The sky survey could detect Arecibo at >>approximately 50 ly, and the targeted search could do so at >>approximately 1000 ly. Which makes me want to ask: How strong are the signals the NASA (& others) use for sending the commands to their remote probes in our solar system? (Of course depending whether they are orbiting nearby Venus or in outskirts, beyond Neptune's orbit.) How often these signals are sent nowadays? > >Thanks for your reply. I hope NASA will keep the international >community of scientists and engineers, many of whom read Usenet, >informed of technical developments and findings. For example, as >a specialist in computer pattern recognition (image analysis) I'd >be interested to hear about algorithms which discriminate signals. > >Considering your examples, as well probable compression and EC encoding >of communications (images, linguistic data), is HRMS restricted to >detecting deep-space ranging signals, or perhaps synchronization signals? > >[I suppose that inhabited planets would track all natural and artificial >objects of their solar systems, for which they might employ advanced >deep-space radar. For example, we will want to avoid being hit by large >meteors or asteriods here or elsewhere.] Yes, probably, but wouldn't it be possible that really advanced civilization would have some entirely different means of detecting them? With some passive method, for example, by detecting the gravitational waves the incoming comets/asteroids cause. (Huh, is this plausible even in principle? I remember that even earth itself produces quite negligible amount of gravitational waves.) And anyway, if they use EM-radar, what frequency is in that case optimal for detecting the incoming bodies? Assuming that radar(s) itself is on the orbit or in other atmosphereless place. Well, let's then assume that civilization is in the 'interplanetary stage', i.e. it has spread to two or more planets of its local system. What is the optimal means of communication across the interplanetary distances? Laser (versus microwaves)? Anyway, whatever it is, it means that: a) In most cases we wouldn't detect those interplanetary communications because their 'ecliptic' plane doesn't happen to point to earth. b) And even then we would be 'in beam' only short period of time (hours? days? weeks?) once in every few months/years. (???) This doesn't matter with interplanetary radars, however, because they would probably scan every sector of sky, as comets can come from almost any direction. (Or so I have understood.) >D.H. -- Antti Karttunen / karttu@mits.mdata.fi / $B%"%s%C%F%#!!%+%k%C%H%%%M%s(J ++ Think positively, ota olvia, and vote YES! ------------------------------ Date: 19 Oct 92 19:31:49 GMT From: pawel@tethys.ph.albany.edu Subject: V-2's launched at Russia Newsgroups: sci.space,soc.history In article <29081@scicom.AlphaCDC.COM>, wats@scicom.AlphaCDC.COM (Bruce Watson) writes: >In article |In article <28404@scicom.AlphaCDC.COM| wats@scicom.AlphaCDC.COM (Bruce Watson) writes: >| >|Where any V-2's launched at Russia? >| - Elliott > >Not enough range, 260 miles was the maximum. I don't why none were fired >eastward at the advancing Russian Army. > >-- >Bruce Watson (wats@scicom) Tumbra, Zorkovick; Sparkula zoom krackadomando. The accuracy was not enough ... V2 was basically the mean of terror aggainst civilian population - it could have been used only against major cities (check the list in the original poster). It wasn't accurat enough even to hit the factory or anything like that. Directing against the advancing army was out of the question. Pawel Penczek ------------------------------ Date: 19 Oct 92 23:00:04 GMT From: Josh 'K' Hopkins Subject: Weather satellites & preventing property damage Newsgroups: sci.space Frederick.A.Ringwald@dartmouth.edu (Frederick A. Ringwald) writes: >Does anyone have figures for how much property damage has been >prevented because of data from weather satellites? More interestingly, >does it justify the entire NASA budget, for all time? I don't know about property damage, but I can give an example measured in human lives (and I'm not about to give the exchange rate). When I went down to Houston, I picked up all those Chamber of Commerce weclome-to-town-here's-what- we're-all-about booklets. One of them mentioned that a hurricane had struck the Galveston-Houston area around the turn of the century and killed something like 6,000 people. You may rember a hurricane which hit Florida recently. Despite being one of the worst on record and hitting a much larger population, the last death toll I heard was under 20. I think hurricanes are the only major natural disaster we can predict reliably enough that people take it seriously and far enough in advance to do much good. -- Josh Hopkins jbh55289@uxa.cso.uiuc.edu The views expresed above do not necessarily reflect those of ISDS, UIUC, NSS, IBM FSC, NCSA, NMSU, AIAA or the American Association for the Advancement of Acronymphomaniacs ------------------------------ End of Space Digest Volume 15 : Issue 328 ------------------------------