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Date: Tue, 20 Oct 92 05:02:13
From: Space Digest maintainer <digests@isu.isunet.edu>
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 <your name>" 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 <mmf@evolving.com>
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 <jechilde@unccsun.uncc.edu>
Subject: Earth's two moons
Newsgroups: sci.space
In article <Bw8Gn4.1wJ@csugrad.cs.vt.edu> 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 <mcgrath@cs.uiuc.edu>
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" <dong@oakhill.sps.mot.com>
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 <WAF102@psuvm.psu.edu> 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 <Cohena@mdc.com>
Subject: Jobs-Aerospace
Newsgroups: sci.space
In article <92289.130301WAF102@psuvm.psu.edu>, William Fabanich
<WAF102@psuvm.psu.edu> 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 <karttu@mits.mdata.fi>
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 <elliott.14@oliafd.shel.isc-br.com| elliott@oliafd.shel.isc-br.com (Elliott Kleinrock) writes:
>|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 <jbh55289@uxa.cso.uiuc.edu>
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
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End of Space Digest Volume 15 : Issue 328
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