Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V16_5/V16NO532.TXT

Internet Message Format | 1993-07-13 | 30KB

Date: Wed,  5 May 93 07:59:10
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V16 #532
To: Space Digest Readers
Precedence: bulk


Space Digest                Wed,  5 May 93       Volume 16 : Issue 532

Today's Topics:
                 Astro/Space Frequently Seen Acronyms
                  Cape York is dead; Long Live PNG!
                         Drag-free satellites
                 Gamma Ray Bursters. WHere are they.
                        HST Servicing Mission
                    large accelerations revisited
                     Looking for DC-X ftp source
                    Philosophy Quest.  How Boldly?

    Welcome to the Space Digest!!  Please send your messages to
    "[e-mail]", 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 [e-mail] (Internet).
----------------------------------------------------------------------

Date: 5 May 1993 00:00:10 -0400
From: Mark Bradford <[e-mail]>
Subject: Astro/Space Frequently Seen Acronyms
Newsgroups: sci.astro,sci.space,sci.space.shuttle,news.answers

Archive-name: space/acronyms
Edition: 8

Acronym List for sci.astro, sci.space, and sci.space.shuttle:
Edition 8, 1992 Dec 7
Last posted: 1992 Aug 27

This list is offered as a reference for translating commonly appearing
acronyms in the space-related newsgroups.  If I forgot or botched your
favorite acronym, please let me know!  Also, if there's an acronym *not*
on this list that confuses you, drop me a line, and if I can figure
it out, I'll add it to the list.

Note that this is intended to be a reference for *frequently seen*
acronyms, and is most emphatically *not* encyclopedic.  If I incorporated
every acronym I ever saw, I'd soon run out of disk space!  :-)

The list will be posted at regular intervals, every 30 days.  All
comments regarding it are welcome; I'm reachable as [e-mail].

Note that this just tells what the acronyms stand for -- you're on your
own for figuring out what they *mean*!  Note also that the total number of
acronyms in use far exceeds what I can list; special-purpose acronyms that
are essentially always explained as they're introduced are omitted.
Further, some acronyms stand for more than one thing; as of Edition 3 of
the list, these acronyms appear on multiple lines, unless they're simply
different ways of referring to the same thing.

Thanks to everybody who's sent suggestions since the first version of
the list, and especially to Garrett A. Wollman ([e-mail]),
who is maintaining an independent list, somewhat more verbose in
character than mine, and to Daniel Fischer ([e-mail]),
who is maintaining a truly HUGE list (535 at last count) of acronyms and
terms, mostly in German (which I read, fortunately).

Special thanks this time to Ken Hollis at NASA, who sent me a copy of NASA
Reference Publication 1059 Revised: _Space Transportation System and
Associated Payloads: Glossary, Acronyms, and Abbreviations_, a truly
mammoth tome -- almost 300 pages of TLAs.

Special Bonus!  At the end of this posting, you will find a perl program
written by none other than Larry Wall, whose purpose is to scramble the
acronym list in an entertaining fashion.  Thanks, Larry!

A&A: Astronomy and Astrophysics
AAO: Anglo-Australian Observatory
AAS: American Astronomical Society
AAS: American Astronautical Society
AAVSO: American Association of Variable Star Observers
ACE: Advanced Composition Explorer
ACRV: Assured Crew Return Vehicle (or) Astronaut Crew Rescue Vehicle
ADFRF: Ames-Dryden Flight Research Facility (was DFRF) (NASA)
AGN: Active Galactic Nucleus
AGU: American Geophysical Union
AIAA: American Institute of Aeronautics and Astronautics
AIPS: Astronomical Image Processing System
AJ: Astronomical Journal
ALEXIS: Array of Low Energy X-ray Imaging Sensors
ALPO: Association of Lunar and Planetary Observers
ALS: Advanced Launch System
ANSI: American National Standards Institute
AOA: Abort Once Around (Shuttle abort plan)
AOCS: Attitude and Orbit Control System
Ap.J: Astrophysical Journal
APM: Attached Pressurized Module (a.k.a. Columbus)
APU: Auxiliary Power Unit
ARC: Ames Research Center (NASA)
ARTEMIS: Advanced Relay TEchnology MISsion
ASA: Astronomical Society of the Atlantic
ASI: Agenzia Spaziale Italiano
ASRM: Advanced Solid Rocket Motor
ATDRS: Advanced Tracking and Data Relay Satellite
ATLAS: Atmospheric Laboratory for Applications and Science
ATM: Amateur Telescope Maker
ATO: Abort To Orbit (Shuttle abort plan)
AU: Astronomical Unit
AURA: Association of Universities for Research in Astronomy
AW&ST: Aviation Week and Space Technology (a.k.a. AvLeak)
AXAF: Advanced X-ray Astrophysics Facility
BATSE: Burst And Transient Source Experiment (on CGRO)
BBXRT: Broad-Band X-Ray Telescope (ASTRO package)
BEM: Bug-Eyed Monster
BH: Black Hole
BIMA: Berkeley Illinois Maryland Array
BNSC: British National Space Centre
BTW: By The Way
C&T: Communications & Tracking
CCAFS: Cape Canaveral Air Force Station
CCD: Charge-Coupled Device
CCDS: Centers for the Commercial Development of Space
CD-ROM: Compact Disk Read-Only Memory
CFA: Center For Astrophysics
CFC: ChloroFluoroCarbon
CFF: Columbus Free Flyer
CFHT: Canada-France-Hawaii Telescope
CGRO: (Arthur Holley) Compton Gamma Ray Observatory (was GRO)
CHARA: Center for High Angular Resolution Astronomy
CIRRIS: Cryogenic InfraRed Radiance Instrument for Shuttle
CIT: Circumstellar Imaging Telescope
CM: Command Module (Apollo spacecraft)
CMCC: Central Mission Control Centre (ESA)
CNES: Centre National d'Etude Spatiales
CNO: Carbon-Nitrogen-Oxygen
CNSR: Comet Nucleus Sample Return
COBE: COsmic Background Explorer
COMPTEL: COMPton TELescope (on CGRO)
COSTAR: Corrective Optics Space Telescope Axial Replacement
CRAF: Comet Rendezvous / Asteroid Flyby
CRRES: Combined Release / Radiation Effects Satellite
CSM: Command and Service Module (Apollo spacecraft)
CSTC: Consolidated Satellite Test Center (USAF)
CTIO: Cerro Tololo Interamerican Observatory
DCX: Delta Clipper eXperimental
DDCU: DC-to-DC Converter Unit
DFRF: Dryden Flight Research Facility (now ADFRF)
DMSP: Defense Meteorological Satellite Program
DOD: Department Of Defense (sometimes DoD)
DOE: Department Of Energy
DOT: Department Of Transportation
DSCS: Defense Satellite Communications System
DSN: Deep Space Network
DSP: Defense Support Program (USAF/NRO)
EAFB: Edwards Air Force Base
ECS: Environmental Control System
EDO: Extended Duration Orbiter
EGRET: Energetic Gamma Ray Experiment Telescope (on CGRO)
EJASA: Electronic Journal of the Astronomical Society of the Atlantic
ELV: Expendable Launch Vehicle
EMU: Extravehicular Mobility Unit
EOS: Earth Observing System
ERS: Earth Resources Satellite (as in ERS-1)
ESA: European Space Agency
ESO: European Southern Observatory
ET: (Shuttle) External Tank
ETLA: Extended Three Letter Acronym
ETR: Eastern Test Range
EUV: Extreme UltraViolet
EUVE: Extreme UltraViolet Explorer
EVA: ExtraVehicular Activity
FAQ: Frequently Asked Questions
FAST: Fast Auroral SnapshoT explorer
FFT: Fast Fourier Transform
FGS: Fine Guidance Sensors (on HST)
FHST: Fixed Head Star Trackers (on HST)
FIR: Far InfraRed
FITS: Flexible Image Transport System
FOC: Faint Object Camera (on HST)
FOS: Faint Object Spectrograph (on HST)
FRR: Flight-Readiness Review
FTP: File Transfer Protocol
FTS: Flight Telerobotic Servicer
FUSE: Far Ultraviolet Spectroscopic Explorer
FWHM: Full Width at Half Maximum
FYI: For Your Information
GAS: Get-Away Special
GBT: Green Bank Telescope
GCVS: General Catalog of Variable Stars
GEM: Giotto Extended Mission
GEO: Geosynchronous Earth Orbit
GDS: Great Dark Spot
GHRS: Goddard High Resolution Spectrograph (on HST)
GIF: Graphics Interchange Format
GLOMR: Global Low-Orbiting Message Relay
GMC: Giant Molecular Cloud
GMRT: Giant Meter-wave Radio Telescope
GMT: Greenwich Mean Time (also called UT)
GOES: Geostationary Orbiting Environmental Satellite
GOX: Gaseous OXygen
GPC: General Purpose Computer
GPS: Global Positioning System
GRO: Gamma Ray Observatory (now CGRO)
GRS: Gamma Ray Spectrometer (on Mars Observer)
GRS: Great Red Spot
GSC: Guide Star Catalog (for HST)
GSFC: Goddard Space Flight Center (NASA)
GTO: Geostationary Transfer Orbit
HAO: High Altitude Observatory
HD: Henry Draper catalog entry
HEAO: High Energy Astronomical Observatory
HeRA: Hermes Robotic Arm
HF: High Frequency
HGA: High Gain Antenna
HLC: Heavy Lift Capability
HLV: Heavy Lift Vehicle
HMC: Halley Multicolor Camera (on Giotto)
HR: Hertzsprung-Russell (diagram)
HRI: High Resolution Imager (on ROSAT)
HSP: High Speed Photometer (on HST)
HST: Hubble Space Telescope
HUT: Hopkins Ultraviolet Telescope (ASTRO package)
HV: High Voltage
IAPPP: International Amateur/Professional Photoelectric Photometry
IAU: International Astronomical Union
IAUC: IAU Circular
ICE: International Cometary Explorer
IDA: International Dark-sky Association
IDL: Interactive Data Language
IGM: InterGalactic Medium
IGY: International Geophysical Year
IMHO: In My Humble Opinion
IOTA: Infrared-Optical Telescope Array
IOTA: International Occultation Timing Association
IPS: Inertial Pointing System
IR: InfraRed
IRAF: Image Reduction and Analysis Facility
IRAS: InfraRed Astronomical Satellite
ISAS: Institute of Space and Astronautical Science (Japan)
ISM: InterStellar Medium
ISO: Infrared Space Observatory
ISO: International Standards Organization
ISPM: International Solar Polar Mission (now Ulysses)
ISY: International Space Year
IUE: International Ultraviolet Explorer
IUS: Inertial Upper Stage
JEM: Japanese Experiment Module (for SSF)
JGR: Journal of Geophysical Research
JILA: Joint Institute for Laboratory Astrophysics
JPL: Jet Propulsion Laboratory
JSC: Johnson Space Center (NASA)
KAO: Kuiper Airborne Observatory
KPNO: Kitt Peak National Observatory
KSC: Kennedy Space Center (NASA)
KTB: Cretaceous-Tertiary Boundary (from German)
LANL: Los Alamos National Laboratory
LaRC: Langley Research Center (NASA)
LDEF: Long Duration Exposure Facility
LEM: Lunar Excursion Module (a.k.a. LM) (Apollo spacecraft)
LEO: Low Earth Orbit
LeRC: Lewis Research Center (NASA)
LEST: Large Earth-based Solar Telescope
LFSA: List of Frequently Seen Acronyms (!)
LGA: Low Gain Antenna
LGM: Little Green Men
LH: Liquid Hydrogen (also LH2 or LHX)
LLNL: Lawrence-Livermore National Laboratory
LM: Lunar Module (a.k.a. LEM) (Apollo spacecraft)
LMC: Large Magellanic Cloud
LN2: Liquid N2 (Nitrogen)
LOX: Liquid OXygen
LRB: Liquid Rocket Booster
LSR: Local Standard of Rest
LTP: Lunar Transient Phenomenon
MB: Manned Base
MCC: Mission Control Center
MECO: Main Engine CutOff
MMH: MonoMethyl Hydrazine
MMT: Multiple Mirror Telescope
MMU: Manned Maneuvering Unit
MNRAS: Monthly Notices of the Royal Astronomical Society
MOC: Mars Observer Camera (on Mars Observer)
MOL: Manned Orbiting Laboratory
MOLA: Mars Observer Laser Altimeter (on Mars Observer)
MOMV: Manned Orbital Maneuvering Vehicle
MOTV: Manned Orbital Transfer Vehicle
MPC: Minor Planets Circular
MRSR: Mars Rover and Sample Return
MRSRM: Mars Rover and Sample Return Mission
MSFC: (George C.) Marshall Space Flight Center (NASA)
MTC: Man Tended Capability
NACA: National Advisory Committee on Aeronautics (became NASA)
NASA: National Aeronautics and Space Administration
NASDA: NAtional Space Development Agency (Japan)
NASM: National Air and Space Museum
NASP: National AeroSpace Plane
NBS: National Bureau of Standards (now NIST)
NDV: NASP Derived Vehicle
NERVA: Nuclear Engine for Rocket Vehicle Application
NGC: New General Catalog
NICMOS: Near Infrared Camera / Multi Object Spectrometer (HST upgrade)
NIMS: Near-Infrared Mapping Spectrometer (on Galileo)
NIR: Near InfraRed
NIST: National Institute for Standards and Technology (was NBS)
NLDP: National Launch Development Program
NOAA: National Oceanic and Atmospheric Administration
NOAO: National Optical Astronomy Observatories
NRAO: National Radio Astronomy Observatory
NRO: National Reconnaissance Office
NS: Neutron Star
NSA: National Security Agency
NSF: National Science Foundation
NSO: National Solar Observatory
NSSDC: National Space Science Data Center
NTR: Nuclear Thermal Rocket(ry)
NTT: New Technology Telescope
OAO: Orbiting Astronomical Observatory
OCST: Office of Commercial Space Transportation
OMB: Office of Management and Budget
OMS: Orbital Maneuvering System
OPF: Orbiter Processing Facility
ORFEUS: Orbiting and Retrievable Far and Extreme Ultraviolet Spectrometer
OSC: Orbital Sciences Corporation
OSCAR: Orbiting Satellite Carrying Amateur Radio
OSSA: Office of Space Science and Applications
OSSE: Oriented Scintillation Spectrometer Experiment (on CGRO)
OTA: Optical Telescope Assembly (on HST)
OTHB: Over The Horizon Backscatter
OTV: Orbital Transfer Vehicle
OV: Orbital Vehicle
PAM: Payload Assist Module
PAM-D: Payload Assist Module, Delta-class
PI: Principal Investigator
PLSS: Portable Life Support System
PM: Pressurized Module
PMC: Permanently Manned Capability
PMIRR: Pressure Modulated InfraRed Radiometer (on Mars Observer)
PMT: PhotoMultiplier Tube
PSF: Point Spread Function
PSR: PulSaR
PV: Photovoltaic
PVO: Pioneer Venus Orbiter
QSO: Quasi-Stellar Object
RCI: Rodent Cage Interface (for SLS mission)
RCS: Reaction Control System
REM: Rat Enclosure Module (for SLS mission)
RF: Radio Frequency
RFI: Radio Frequency Interference
RIACS: Research Institute for Advanced Computer Science
RMS: Remote Manipulator System
RNGC: Revised New General Catalog
ROSAT: ROentgen SATellite
ROUS: Rodents Of Unusual Size (I don't believe they exist)
RSN: Real Soon Now
RTG: Radioisotope Thermoelectric Generator
RTLS: Return To Launch Site (Shuttle abort plan)
SAA: South Atlantic Anomaly
SAGA: Solar Array Gain Augmentation (for HST)
SAMPEX: Solar Anomalous and Magnetospheric Particle EXplorer
SAO: Smithsonian Astrophysical Observatory
SAR: Search And Rescue
SAR: Synthetic Aperture Radar
SARA: Satellite pour Astronomie Radio Amateur
SAREX: Search and Rescue Exercise
SAREX: Shuttle Amateur Radio Experiment
SAS: Space Activity Suit
SAS: Space Adaptation Syndrome
SAT: Synthetic Aperture Telescope
S/C: SpaceCraft
SCA: Shuttle Carrier Aircraft
SCT: Schmidt-Cassegrain Telescope
SDI: Strategic Defense Initiative
SDIO: Strategic Defense Initiative Organization
SEI: Space Exploration Initiative
SEST: Swedish ESO Submillimeter Telescope
SETI: Search for ExtraTerrestrial Intelligence
SID: Sudden Ionospheric Disturbance
SIR: Shuttle Imaging Radar
SIRTF: Space (formerly Shuttle) InfraRed Telescope Facility
SL: SpaceLab
SLAR: Side-Looking Airborne Radar
SLC: Space Launch Complex
SLS: Space(lab) Life Sciences
SMC: Small Magellanic Cloud
SME: Solar Mesosphere Explorer
SMEX: SMall EXplorers
SMM: Solar Maximum Mission
SN: SuperNova (e.g., SN1987A)
SNR: Signal to Noise Ratio
SNR: SuperNova Remnant
SNU: Solar Neutrino Units
SOFIA: Stratospheric Observatory For Infrared Astronomy
SOHO: SOlar Heliospheric Observatory
SPAN: Space Physics and Analysis Network
SPDM: Special Purpose Dextrous Manipulator
SPOT: Systeme Probatoire pour l'Observation de la Terre
SPS: Solar Power Satellite
SRB: Solid Rocket Booster
SRM: Solid Rocket Motor
SSF: Space Station Fred (er, Freedom)
SSI: Solid-State Imager (on Galileo)
SSI: Space Studies Institut
SSME: Space Shuttle Main Engine
SSPF: Space Station Processing Facility
SSRMS: Space Station Remote Manipulator System
SST: Spectroscopic Survey Telescope
SST: SuperSonic Transport
SSTO: Single Stage To Orbit
STIS: Space Telescope Imaging Spectrometer (to replace FOC and GHRS)
STS: Shuttle Transport System (or) Space Transportation System
STScI: Space Telescope Science Institute
SWAS: Submillimeter Wave Astronomy Satellite
SWF: ShortWave Fading
TAL: Transatlantic Abort Landing (Shuttle abort plan)
TAU: Thousand Astronomical Unit (mission)
TCS: Thermal Control System
TDRS: Tracking and Data Relay Satellite
TDRSS: Tracking and Data Relay Satellite System
TES: Thermal Emission Spectrometer (on Mars Observer)
TIROS: Television InfraRed Observation Satellite
TLA: Three Letter Acronym
TOMS: Total Ozone Mapping Spectrometer
TPS: Thermal Protection System
TSS: Tethered Satellite System
UARS: Upper Atmosphere Research Satellite
UBM: Unpressurized Berthing Mechanism
UDMH: Unsymmetrical DiMethyl Hydrazine
UFO: Unidentified Flying Object
UGC: Uppsala General Catalog
UHF: Ultra High Frequency
UIT: Ultraviolet Imaging Telescope (Astro package)
UKST: United Kingdom Schmidt Telescope
USAF: United States Air Force
USMP: United States Microgravity Payload
UT: Universal Time (a.k.a. GMT, UTC, or Zulu Time)
UTC: Coordinated Universal Time (a.k.a. UT)
UV: UltraViolet
UVS: UltraViolet Spectrometer
VAB: Vehicle Assembly Building (formerly Vertical Assembly Building)
VAFB: Vandenberg Air Force Base
VEEGA: Venus-Earth-Earth Gravity Assist (Galileo flight path)
VHF: Very High Frequency
VLA: Very Large Array
VLBA: Very Long Baseline Array
VLBI: Very Long Baseline Interferometry
VLF: Very Low Frequency
VLT: Very Large Telescope
VMS: Vertical Motion Simulator
VOIR: Venus Orbiting Imaging Radar (superseded by VRM)
VPF: Vertical Processing Facility
VRM: Venus Radar Mapper (now called Magellan)
WD: White Dwarf
WFPC: Wide Field / Planetary Camera (on HST)
WFPCII: Replacement for WFPC
WIYN: Wisconsin / Indiana / Yale / NOAO telescope
WSMR: White Sands Missile Range
WTR: Western Test Range
WUPPE: Wisconsin Ultraviolet PhotoPolarimter Experiment (Astro package)
XMM: X-ray Multi Mirror
XUV: eXtreme UltraViolet
YSO: Young Stellar Object


#!/usr/bin/perl
# 'alt', An Acronym Scrambling Program, by Larry Wall

$THRESHOLD = 2;

srand;
while (<>) {
    next unless /^([A-Z]\S+): */;
    $key = $1;
    $acro{$key} = $';
    @words = split(/\W+/,$');
    unshift(@words,$key);
    $off = 0;
    foreach $word (@words) {
        next unless $word =~ /^[A-Z]/;
        *w = $&;
        vec($w{$word}, $off++ % 6, 1) = 1;
    }
}

foreach $letter (A .. Z) {
    *w = $letter;
    @w = keys %w;
    if (@w < $THRESHOLD) {
        @d = `egrep '^$letter' /usr/dict/words`;
        chop @d;
        push(@w, @d);
    }
}

foreach $key (sort keys %acro) {
    $off = 0;
    $acro = $acro{$key};
    $acro =~ s/((([A-Z])[A-Z]*)[a-z]*)/ &pick($3, $2, $1, ++$off) || $& /eg;
    print "$key: $acro";
}

sub pick {
    local($letter, $prefix, $oldword, $off) = @_;
    $i = 0;
    if (length($prefix) > 1 && index($key,$prefix) < 0) {
        if ($prefix eq $oldword) {
            $prefix = '';
        }
        else {
            $prefix = $letter;
        }
    }
    if (length($prefix) > 1) {
        local(*w) = substr($prefix,0,1);
        do {
            $word = $w[rand @w];
        } until $word ne $oldword && $word =~ /^$prefix/i || ++$i > 30;
        $word =~ s/^$prefix/$prefix/i;
        $word;
    }
    elsif (length($prefix) == 1) {
        local(*w) = $prefix;
        do {
            $word = $w[rand @w];
        } until $word ne $oldword && vec($w{$word}, $off, 1) || ++$i > 10;
        $word = "\u\L$word" if $word =~ tr/a-z/A-Z/;
        $word;
    }
    else {
        local(*w) = substr($oldword,0,1);
        do {
            $word = $w[rand @w];
        } until $word ne $oldword && $word =~ tr/a-z/A-Z/ == 0 || ++$i > 30;
        $word;
    }
}


-- Mark Bradford ([e-mail]) <> To err is human, to moo bovine.
                  "It's an ill wind that gathers no moss."

------------------------------

Date: Wed, 5 May 93 05:00:11 GMT
From: Michael Nielsen <[e-mail]>
Subject: Cape York is dead; Long Live PNG!
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Gregory N. Bond) writes:
>A story appeard on the (Australian) ABC radio news last night that is
>of interest.  It is also mentioned in "The Australian Financial
>Review" this morning (4/5/93), p14.  (Don't say I don't give
>references!)
>
>Space Transportation Systems is the company that was the preferred
>bidder for the Cape York space port, with a prominant polititian
>(Ahern, ex-Premier of Queensland) at its head.  There was a
>one-last-time, firm-and-this-time-we-mean-it deadline for STS to line
>up funding for CY that expired without a whisper in December.
>
>Last night there was an announcement by the Prime Minister of Papua
>New Guinea (PNG, an island nation to the north of Australia and east
>of Indonesia - basically half the huge blob just north of Cape York,
>the pointy bit on the east edge of Australia that was the preferred
>site for the space port.).  STS has been given an in-principle
>go-ahead for the establishmnent of a commercial spaceport on an as-yet
>unchosen PNG equatorial island.  The project was predicted to cost
>about $USD 920m.  Talks with internation funding sources are

    $US0.920 that extremelly cheap :-> (m == 10^-3 usually).

>continuing, and STS is "confident about their success."  A feasability
>study (a $mil or so) is about to begin and could be completed by the
>end of 1993.
>
>This pretty much implies that Cape York is dead, and the report said
>as much.  More details as they come to hand.


    Sorry I just couldn't help my self


        mike
--
-----------------------------------------------------------------------
    JOKE == (:->)            Michael Nielsen @ 1993
    [e-mail]        Disclamer :- I'm Innocent
------------------------------------------------------------------------

------------------------------

Date: 4 May 93 11:35:19 GMT
From: [e-mail]
Subject: Drag-free satellites
Newsgroups: sci.space

[e-mail] (Isaac Kuo) writes:

>
> Well, you can certainly express any smooth function as the sum of an infinite
> number of harmonic functions.  I wouldn't, and neither would any other
> mathematician, call such summands "harmonics".
>

As a mathematician myself, I'd call the terms harmonics, by extension to the
general (musical) usage.  Jargon, prehaps, but standard jargon.


> In any case, the small difference from spherical that the Earth is is
> ridiculously small.  Even counting all of the mountains, etc. that make the
> Earth bumpy, the Earth is closer to a sphere than the smoothest billiard
> ball.
>
> Even if the Earth were significantly flattenned, it would be flattenned on
> the axis of rotation, and thus the gravitational field does not rotate and
> thus no orbiting satellite can derive energy from the non-changing
> gravitational field.

The difference between polar & equatorial diameters is ~1/300 diameter;
and there *are* non rotationally symmetric distortions; which are in the
main generated by density gradients & movements in the mantle.

------------------------------

Date: 5 May 1993 03:29:57 GMT
From: "David M. Palmer" <[e-mail]>
Subject: Gamma Ray Bursters. WHere are they.
Newsgroups: sci.astro,sci.space

Lines: 24
Message-Id: <[e-mail]>
References: <1radsr$[e-mail]> <[e-mail]> <[e-mail]> <[e-mail]>
Nntp-Posting-Host: alumni.caltech.edu
Sender: [e-mail]
Source-Info:  Sender is really [e-mail]

[e-mail] (Ross Smith) writes:

>I don't know what you mean by 'edged', but surely there are two other
>possibilities for an isotropic distribution: near interstellar (up to
>~100 pc, i.e. within the disc), or the Galaxy's corona?

You see fewer faint (presumably distant) bursts than you would expect from
the number of bright (presumably nearby) bursts, assuming that they are
uniformly distributed in space for as far as we can see.
We are near (within 10% of) the center of a spherical distribution
of gamma-ray burst sources.

Near insterstellar would not show the deficit of faint bursts.
Galactic Halo sources would have to be distributed with a
typical radius of ~80 kpc (we are at ~8 kpc from the Galactic center).

About half the people in the field mostly believe, (and most
people about half believe), that GRBs are from our Galaxy, according
to a show of hands at a conference last October.  But top scientists
are still baffled, as the press would say.

--
        David M. Palmer        [e-mail]
                    [e-mail]

------------------------------

Date: 5 May 1993 01:44:00 -0700
From: Dan Tilque <[e-mail]>
Subject: HST Servicing Mission
Newsgroups: sci.space,sci.space.shuttle,sci.astro

>[e-mail] (Pat) writes:
>>
>> After all the space walking,  they are going to  re-boost the HST's
>> orbit.  I think right now  it's sitting  at 180 miles up,
>> they would like  220.

If it's currently at 180 miles altitude, it's dropped considerably
since it was launched.  The original orbit was about 600 Km, if I
recall correctly.

---
Dan Tilque    --     [e-mail]

------------------------------

Date: Wed, 5 May 1993 04:56:19 GMT
From: Gary Coffman <ke4zv!gary>
Subject: large accelerations revisited
Newsgroups: sci.space

In article <1s4olt$[e-mail]> [e-mail] (Pat) writes:
>
>Of course, if you are going to de-couple the pilot from the physical
>frame of the aircraft,  both in positioning and sensor systems.
>Control systems have been decoupled for the last 10 years.
>
>Why not go the distance and remove the pilot.  If he has to fly using
>a virtual reality helmet,  take him out of the aircraft,  and make it
>a "guided"  missile.   kinda like a next generation  smart bomb.

The problem breaks down into two parts. First is the technical problem
of achieving the necessary bandwidth in the face of hostile action.
It's difficult enough under the best of conditions to achieve the high
bandwidth required to VR a pilot's senses, but when the enemy is actively
trying to interfere, and the airspace and spectrum aren't constrained,
the problem becomes very severe. A short fiber optic link is much
easier to implement than open spectrum high bandwidth transmissions.
Aside from merely implementing the link, a difficult enough challenge,
the link's integrity must be ensured against jamming, spoofing, and
capture. That adds considerable overhead to an already heavily burdened
channel.

The second part of the problem is psychological. A pilot on board is
more highly motivated than a controller snug in a bunker hundreds of
miles from the action. This shouldn't be discounted lightly. While
the performance of the aircraft can be improved when not constrained
by a pilot's physical limitations, the lesser degree to which the
controller identifies with the aircraft and it's mission may negate
these improvements in actual tactical situations.

Gary
--
Gary Coffman KE4ZV          |    You make it,     | gatech!wa4mei!ke4zv!gary
Destructive Testing Systems |    we break it.     | uunet!rsiatl!ke4zv!gary
534 Shannon Way             |    Guaranteed!      | emory!kd4nc!ke4zv!gary
Lawrenceville, GA 30244     |                     |

------------------------------

Date: 5 May 1993 00:33:41 GMT
From: steve hix <[e-mail]>
Subject: Looking for DC-X ftp source
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (David L. Sobin) writes:
>I understand that there is an ftp site somewhere that has the latest info
>on DC-X. If anyone knows the address, could you post or direct e-mail?

The current (June, 1993) issue of Analog has a nice article outlining the
DC project goals and all.  Even a few sketches.




--
"...Then anyone who leaves behind him a written manual, and likewise
anyone who receives it, in the belief that such writing will be clear
and certain, must be exceedingly simple-minded..."   Plato, _Phaedrus_
-------------------------------------------------------

------------------------------

Date: Wed, 5 May 93 04:56:52 GMT
From: Michael Nielsen <[e-mail]>
Subject: Philosophy Quest.  How Boldly?
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (steve hix) writes:
>In article <[e-mail]> [e-mail] (Bob Kierski) writes:
>>In article <[e-mail]>, [e-mail] (Henry Spencer) writes:
>>
>
>It's not even that easy:
>
>Unless, when we come across an alien culture, we remain invisible to them, the
>fact that they know we're there is probably going to have an immense effect on
>them.
>
>An alien culture stumbling over us will also have an immense impact on us, one
>that might even destroy our culture, intentionally or not.
>
>It's not necessary that we force our culture on the others at all.

    Yes however I will argue the fact that every encounter between
cultures on earth there has been one which is  more "powerful" than the
other and it has been used to destroy the weaker culture, rather than
co-existing with it. (And it has been a choice to destroy the other
culture in all the cases known to me), I cannot recall a single instance in
history where this has not happened. (of course I am not a historian)

    I believe that was what the original author was referring (I
could very well be wrong), and I may have added a  personal view
point to it.


    mike
--
-----------------------------------------------------------------------
    JOKE == (:->)            Michael Nielsen @ 1993
    [e-mail]        Disclamer :- I'm Innocent
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End of Space Digest Volume 16 : Issue 532
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