Search the FAQ Archives

3 - A - B - C - D - E - F - G - H - I - J - K - L - M
N - O - P - Q - R - S - T - U - V - W - X - Y - Z - Internet FAQ Archives

Astro/Space Frequently Seen Acronyms

[ Usenet FAQs | Web FAQs | Documents | RFC Index | Forum ]
Archive-name: space/acronyms

See reader questions & answers on this topic! - Help others by sharing your knowledge
Acronym List for Space and Astronomy
As of 2006 May 4

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.

The canonical version of this list is the HTML form, available at . From that, I generate the text form for USENET

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 at
NOTE: Due to the high level of spam I receive, you must include the
text "tla" in the Subject header of your e-mail, or I will never see
your message.

Note that this list 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;
these acronyms appear on multiple lines.

Thanks to everybody who's sent suggestions since the first version of the list!

PS: Strictly speaking, most of these are "initialisms" or
"abbreviations" rather than "acronyms"; pedantically, it's only an
"acronym" if you make a word out of it, like "laser" or "radar." In
practice, though, everybody calls 'em acronyms.

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
AD:        Analog to Digital
ADFRF:     Ames-Dryden Flight Research Facility (now DFRC) (NASA)
AFAIK:     As Far As I Know
AGN:       Active Galactic Nucleus
AGU:       American Geophysical Union
AIAA:      American Institute of Aeronautics and Astronautics
AIPS:      Astronomical Image Processing System
AIT:       Assembly, Integration, and Testing
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)
AOA:       Angle Of Attack
AOCS:      Attitude and Orbit Control System
Ap.J:      Astrophysical Journal
APL:       Applied Physics Laboratory (at Johns Hopkins)
APM:       Attached Pressurized Module (a.k.a. Columbus)
APU:       Auxiliary Power Unit
ARC:       Ames Research Center (NASA)
ARC:       Astrophysical Research Consortium
ARTEMIS:   Advanced Relay TEchnology MISsion
ASA:       Astronomical Society of the Atlantic
ASC:       Agence Spatiale Canadienne (also CSA)
ASI:       Agenzia Spaziale Italiana
ASP:       Astronomical Society of the Pacific
ASRM:      Advanced Solid Rocket Motor
ATDRS:     Advanced Tracking and Data Relay Satellite
ATLAS:     Atmospheric Laboratory for Applications and Science
ATM:       Amateur Telescope Maker
ATM:       Apollo Telescope Mount (on Skylab)
ATO:       Abort To Orbit
ATV:       Automated Transfer Vehicle
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
BAe:       British Aerospace (now BAE SYSTEMS)
BATSE:     Burst And Transient Source Experiment (on CGRO)
BBXRT:     Broad-Band X-Ray Telescope (ASTRO package)
BDB:       Big Dumb Booster
BEM:       Bug-Eyed Monster
BH:        Black Hole
BIMA:      Berkeley Illinois Maryland Array
BIS:       British Interplanetary Society
BMDO:      Ballistic Missile Defense Office (was SDIO)
BNSC:      British National Space Centre
BTW:       By The Way
CARA:      Center for Astrophysical Research in Antarctica
C&T:       Communications & Tracking
CATS:      Cheap Access To Space
CCAFS:     Cape Canaveral Air Force Station
CCAS:      Cape Canaveral Air Station (now once again CCAFS)
CCD:       Charge-Coupled Device
CCDS:      Centers for the Commercial Development of Space
CD-ROM:    Compact Disc Read-Only Memory
CFA:       Center For Astrophysics
CFC:       ChloroFluoroCarbon
CFF:       Columbus Free Flyer
CFHT:      Canada-France-Hawaii Telescope
CFIT:      Controlled Flight Into Terrain
CG:        Center of Gravity
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)
CM:        Center of Mass
CMBR:      Cosmic Microwave Background Radiation
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
COTS:      Cheap Off The Shelf
CRAF:      Comet Rendezvous / Asteroid Flyby
CRRES:     Combined Release / Radiation Effects Satellite
CSA:       Canadian Space Agency (also ASC)
CSM:       Command and Service Module (Apollo spacecraft)
CSTC:      Consolidated Space Test Center (USAF)
CTIO:      Cerro Tololo Interamerican Observatory
CV:        Cataclysmic Variable
CXBR:      Cosmic X-ray Background Radiation
DC:        Delta Clipper
DCX:       Delta Clipper eXperimental
DDCU:      DC-to-DC Converter Unit
DDTE:      Design, Development, Test, and Evaluation
DFRC:      Dryden Flight Research Center
DFRF:      Dryden Flight Research Facility (was ADFRF, now DFRC)
DMSP:      Defense Meteorological Satellite Program
DOD:       Department Of Defense (sometimes DoD)
DOE:       Department Of Energy
DOT:       Department Of Transportation
DRS:       Data Relay Satellite
DRS:       Direct Receiving Station
DSO:       Deep Sky (or Space) Object
DSCS:      Defense Satellite Communications System
DSN:       Deep Space Network
DSP:       Defense Support Program (USAF/NRO)
EAC:       European Astronaut Centre
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
ER:        Eastern Range (was ETR)
ERS:       Earth Resources Satellite (as in ERS-1)
ESA:       European Space Agency
ESIS:      European Space Information System
ESO:       European Southern Observatory
ESOC:      European Space Operations Centre
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)
FOV:       Field Of View
FRC:       Flight Research Center (old name for DFRC)
FRR:       Flight-Readiness Review
FTETTM:    From The Earth To The Moon
FTL:       Faster Than Light
FTP:       File Transfer Protocol
FTS:       Flight Telerobotic Servicer
FUSE:      Far Ultraviolet Spectroscopic Explorer
FWHM:      Full Width at Half Maximum
FYI:       For Your Information
G:         Gravity
GAS:       Get-Away Special
GBT:       Green Bank Telescope
GCVS:      General Catalog of Variable Stars
GEM:       Giotto Extended Mission
GEM:       Galileo Europa 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
GLOW:      Gross Lift-Off Weight
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
GR:        General Relativity
GRB:       Gamma Ray Burster
GRC:       Glenn Research Center (NASA)
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
GVI:       Global Village Idiot
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)
HOTOL:     HOrizontal TakeOff and Landing (a proposed SSTO craft)
HR:        Hertzsprung-Russell (diagram)
HRMS:      High Resolution Microwave Survey
HRI:       High Resolution Imager (on ROSAT)
HSP:       High Speed Photometer (on HST)
HST:       Hubble Space Telescope
HTH:       Hope This Helps
HTHL:      Horizontal Takeoff Horizontal Landing
HTVL:      Horizontal Takeoff Vertical Landing
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
IIRC:      If I Recall Correctly
IMHO:      In My Humble Opinion
IMO:       International Meteor Organization
INTEGRA:   INTErnational Gamma-Ray Astrophysics Laboratory
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
IRFNA:     Inhibited Red Fuming Nitric Acid
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)
ISPP:      In-Situ Propellant Production
ISS:       International Space Station
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)
L:         Lagrange (as in Lagrange points L1 through L5)
LANL:      Los Alamos National Laboratory
LaRC:      Langley Research Center (NASA)
LASER:     Light Amplification by Stimulated Emission of Radiation
LDEF:      Long Duration Exposure Facility
LEM:       Lunar Excursion Module (a.k.a. LM) (Apollo spacecraft)
LEO:       Low Earth Orbit
LeRC:      Lewis Research Center (NASA; now GRC)
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)
LITVC:     Liquid Injection Thrust Vector Control
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
LPO:       La Palma Observatory
LPV:       Long Period Variable
LRB:       Liquid Rocket Booster
LSR:       Local Standard of Rest
LTP:       Lunar Transient Phenomenon
M:         Messier (as in M31, M13, M57, etcetera)
MACRO:     Monopoles, Astrophysics, and Cosmic Ray Observatory
MB:        Manned Base
MCC:       Mission Control Center
MCD:       Minimum Cost Design
MCO:       Mars Climate Orbiter
MECO:      Main Engine CutOff
MER:       Mars Exploration Rover(s)
MERIS:     Medium Resolution Imaging Spectrometer
MGS:       Mars Global Surveyor
MHD:       MagnetoHydroDynamic
MLI:       Multi-Layer Insulation
MMH:       MonoMethyl Hydrazine
MMT:       Multiple Mirror Telescope
MMU:       Manned Maneuvering Unit
MNRAS:     Monthly Notices of the Royal Astronomical Society
MO:        Mars Observer
MOC:       Mars Observer Camera (on MO and MGS)
MODIS:     Moderate Resolution Imaging Spectroradiometer
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
MPEC:      Minor Planets Electronic Circular
MPL:       Mars Polar Lander
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
NEAR:      Near Earth Asteroid Rendezvous (now named NEAR Shoemaker)
NERVA:     Nuclear Engine for Rocket Vehicle Application
NG:        NewsGroup
NGC:       New General Catalog
NGST:      Next Generation Space Telescope
NICMOS:    Near Infrared Camera / Multi Object Spectrometer (HST upgrade)
NIMS:      Near-Infrared Mapping Spectrometer (on Galileo)
NIR:       Near InfraRed
NIST:      National Institute of Standards and Technology (was NBS)
NLDP:      National Launch Development Program
NOAA:      National Oceanic and Atmospheric Administration
NOAO:      National Optical Astronomy Observatories
NORAD:     NORth American aerospace Defense
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)
OT:        Off-Topic
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
PDS:       Planetary Data System
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
PPM:       Positions and Proper Motions (catalog)
PSF:       Point Spread Function
PSR:       PulSaR
PV:        Photovoltaic
PVO:       Pioneer Venus Orbiter
QSO:       Quasi-Stellar Object
RADAR:     RAdio Detection And Ranging
RAS:       Royal Astronomical Society
RASC:      Royal Astronomical Society of Canada
RCI:       Rodent Cage Interface (for SLS mission)
RCS:       Radar Cross Section
RCS:       Reaction Control System
REM:       Rat Enclosure Module (for SLS mission)
RF:        Radio Frequency
RFI:       Radio Frequency Interference
RFNA:      Red Fuming Nitric Acid
RIACS:     Research Institute for Advanced Computer Science
RMS:       Remote Manipulator System
RNGC:      Revised New General Catalog
ROTFL:     Rolling On The Floor Laughing
ROSAT:     ROentgen SATellite
ROUS:      Rodents Of Unusual Size (I don't believe they exist)
RSA:       Russian Space Agency
RSN:       Radio SuperNova
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:     Space 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 (now BMDO)
SEDS:      Students for the Exploration and Development of Space
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:        (Comet) Shoemaker-Levy
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:      Satellite Pour l'Observation de la Terre
SPS:       Solar Power Satellite
SR:        Special Relativity
SRB:       Solid Rocket Booster
SRM:       Solid Rocket Motor
SSF:       Space Station Fred (er, Freedom) (Superseded by ISS)
SSI:       Solid-State Imager (on Galileo)
SSI:       Space Studies Institut
SSME:      Space Shuttle Main Engine
SSPF:      Space Station Processing Facility
SSPS:      Sky Survey Prototype System
SSRMS:     Space Station Remote Manipulator System
SSRT:      Single Stage Rocket Technology
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
STSDAS:    Space Telescope Science Data Analysis System
SWAS:      Submillimeter Wave Astronomy Satellite
SWF:       ShortWave Fading
TAL:       Transatlantic Abort Landing (Shuttle abort plan)
TANSTAAFL: There Ain't No Such Thing As A Free Lunch
TAU:       Thousand Astronomical Unit (mission)
TCS:       Thermal Control System
TDRS:      Tracking and Data Relay Satellite
TDRSS:     Tracking and Data Relay Satellite System
TEA:       Torque Equilibrium Attitude
TES:       Thermal Emission Spectrometer (on Mars Observer)
THEMIS:    THermal EMission Imaging System (on Mars 2001 Odyssey)
TIROS:     Television InfraRed Observation Satellite
TLA:       Three Letter Acronym
TOMS:      Total Ozone Mapping Spectrometer
TOPS:      Toward Other Planetary Systems
TPS:       Thermal Protection System
TSS:       Targeted Search System
TSS:       Tethered Satellite System
TSTO:      Two Stage To Orbit (also 2STO)
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
USNO:      United States Naval Observatory
UT:        Universal Time (a.k.a. GMT, or Zulu Time; cf UTC)
UTC:       Coordinated Universal Time (subtly different from 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)
VTHL:      Vertical Takeoff Horizontal Landing
VTVL:      Vertical Takeoff Vertical Landing
WD:        White Dwarf
WFF:       Wallops Flight Facility
WFPC:      Wide Field / Planetary Camera (on HST)
WFPCII:    Replacement for WFPC
WIYN:      Wisconsin / Indiana / Yale / NOAO telescope
WR:        Western Range (was WTR)
WSF:       Wake Shield Facility
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
Z:         Zulu (see UT)

-- Mark Bradford ( <> To err is human, to moo bovine.
"It is good to have an open mind, but not at both ends."

User Contributions:

Comment about this article, ask questions, or add new information about this topic:

[ Usenet FAQs | Web FAQs | Documents | RFC Index ]

Send corrections/additions to the FAQ Maintainer: (Mark Bradford)

Last Update March 27 2014 @ 02:12 PM