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HST Acronym List



A Angstrom unit
A ampere
AA Academic Affairs
AAS American Astronomical Society
AB Archive Branch (STScI)
ACE Actuator Control Electronics
ACK acknowldgement message (this is not an acronym)
ACPG Astronomical Community Participation Group (STScI)
ACS Actuator Control System
A/D Analog to Digital
ADC Analog to Digital Converter
ADOR Astrometry and Design Operations Review
ADP Automated Data Processing
AEDP Astrometry and Engineering Data Processing
AGK3 Katalog der Astronomischen Gesellschaft 3
AH ampere hours
AHU Air Handling Unit
AIAA American Institute of Aeronautics and Astronautics
AIPS Astronomical Image Processing System
AJ Astronomical Journal
AMU Atomic mass unit
A/N alphanumeric
ANSI American National Standards Institute
AO Announcement of Opportunity
AOC Award of contract
AP array processor
ApJ Astrophysical Journal
APL Applied Physics Laboratory (JHU)
APS American Physical Society
APSB Advance Planning Systems Branch
ASAP as soon as possible
ASCII American Standard Code for Information Interchange
ASP analog signal processor
ASP Astronomical Society of the Pacific
AST Astrometry (data class)
AST Astrometry Science Team
ASW address and synchronization word
AT acceptance test
ATC Absolute Time Command
AU astronomical unit
AURA Association of Universities for Research in Astronomy, Inc.
AVWG Assembly and Verification Working Group
AXAF Assembly and Verification Working Group
AZ azimuth
BAAS Bulletin of the American Astronomical Society
BASD Ball Aerospace Systems Division
BCD binary coded decimal
BDF block data format
BDEC Bendix Field Engineering Corporation
BER bit error rate
BeV billion electron volts
B/L baseline
BOD board of directors
bpi bits per inch
bps bits per second
BPSK binary phase shift keying
BRAVO Back-End Redesign for Added Value for Observers
BTU British Thermal Unit
B/W black and white
BWI Baltimore-Washington International Airport
C degrees Celsius
CA Coronagraphic Apodizer
C&A calibration and analysis
CADC Canadian Astronomical Data Center (Victoria BC)
CAMAC Computer-Aided Measurement and Control
CAS cost accounting standards
CASB Catalogs And Survey Branch
CASE computer aided software engineering
CBS Contract and Business Services (STScI)
C/C configuration control
CCB Configuration Control Board
CCD charge coupled device
CCIR Consultative Committee on International Radio
CCITT Consultative Committee on International Telegraph & Telephone
CCL closed conference loop
CCR configuration change request
CCTV closed circuit television
CD compact disc
CDBS Calibration Data Base System
CDCA Centre de Depoiullement des Cliches Astronimiques
CD-ROM compact disc-read only memory
CDR critical design review
C&DH Control and Data Handling
CDR Critical Design Review
CIT California Institute of Technology (Pasadena, CA) (do not use CIT, use Caltech)
CKSM checksum
CL command language (IRAF system level)
CM configuration management
cm centimeter
CMOS complimentary metal oxide semiconductor
CM/QA Configuration Management/Quality Assurance
CNS Computing and Network Services (STScI)
CO contracting officer
COB close of business
CODMAC Committee on Data Management and Computing
COSTAR Corrective Optics Space Telescope Axial Replacement
CPAF cost plus award fee
CPFF cost plus fixed fee
CPI characters per inch
CPI Continuous Process Improvement
CPMF cost plus management fee
CPMM characters per millimeter
CPU central processing unit
CRB Change Review Board
CRC cyclic redundancy check
CRT cathode ray tube
CSAA Committee on Space Astronomy and Astrophysics
CSC Computer Sciences Corporation
CSI Catalog of Stellar Identifications
CSLG Campus-wide Software License Grants Program
CTA Computer Technology Associates
CTE charge transfer efficiency
CTIO Cerro Tololo Inter-American Observatory (Chile)
CTWG Calibration Targets Working Group
CU calibration unit (avoid using as an abbreviation, often confused with central unit, camera unit, command unit, etc.)
CV cataclysmic variable star
CV curriculum vitae
CVC Current to Voltage Converter
CVZ continuous viewing zone
CY calendar year
D/A digital to analog
DADS Data Archive and Distribution System
DAO Dominion Astrophysical Observatory (Victoria, BC, Canada)
DAR Defense Acquisition Regulation
DBMS data base management system
DBSA Database and System Administration team (STScI)
dBw decibel reference to 1 watt
DC direct current
DCA Detector Control Assembly
DCB Design Change Board
DCC Document Control Center
DCF Data Capture Facility
DCL Digital Control Language (VAX/VMS)
DCMF Data Capture and Management Facility (GSFC)
DCR document change request
DD Deputy Director
DDCMP Digital Data Communications Message Protocol
DDF Directors Discretionary Fund
DDL Data Definition Language
DE detector efficiency
DEC declination
DEC Digital Equipment Corporation
DEFCAL deflection calibration
DG data group
DH data handling
DMA direct memory access
DMF Data Management Facility
DMS Daily Mission Schedule
DMS Data Management Subsystem
DN digital number
DNA Digital Network Architecture
DOC Data Operations Center
DOD Department of Defense
DOMSAT Domestic Communications Satellite
DOV Director of Orbital Verification
DOY day of year
DQE detector quantum efficiency
DQF data quality file
DRD Data Requirements Document
DSD Data Systems Division (STScI)
DSN Deep Space Network
DSOB Data Systems Operations Branch
E/A ephemeris/attitude
EBA Electronics Bay Assembly
EBS Electron Bombarded Silicon
ECA Electronics Control Assembly
ECF European Coordinating Facility (write as ST-ECF)
EDB Engineering Data Base
EDT eastern daylight time
EED extracted engineering data (file type)
EEO Equal Employment Opportunity
EF Event Foreground (record type)
EIA Electronic Industries Association
ELV expendable launch vehicle
EMI electromagnetic interference
EMU Extra-vehicular Mobility Unit
EOF end of file
EOL end of line
EOR end of record
EOR end of record
EOT end of tape
EOY end of year
EPAO Educational and Public Affairs Office (do not use EPA)
EPS Encapsulated PostScript
EROS Earth Resources Observation Satellite
ERRSAC Eastern Regional Remote Sensing Applications Center
ESA European Space Agency
ESB Engineering Support Branch
ESO European Southern Observatory
ESOC European Space Operations Center
ESS Engineering Support System
EST eastern standard time
ESTEC European Space Technology Center
ESTR Engineering and Science Tape Recorder
ETA estimated time of arrival
ETC STDN station (Greenbelt MD)
ETC estimated time to completion
ETOL ESA Test and Operations Language
ETR Eastern Test Range
ETR Engineering Tape Recorder
ETRD Engineering Tape Recorded Data
EU engineering unit
EUV extreme ultraviolet
EVA extra vehicular activity
F degrees Fahrenheit
FAC facilities
FAC forecast at completion
FACC Ford Aerospace Communications Corporation
FAR Flight Acceptance Review
FAT file allocation table
FD file descriptor
FD flight day (usually used with number, e.g., FD4)
FDI failure detection and isolation
FDR final design review
FEAT Fine Error Averaging Test
FEM Finite Element Model
FES fine error signal
FF flat field (preferred use is to always spell out)
FFT fast Fourier transform
FGE Fine Guidance Electronics
FGS Fine Guidance Sensors (there are three)
FGSAA FGS Access Area
FIFO first in first out (queueing method)
FIPS Federal Information Processing Standards
FITS Flexible Image Transport System
FK4 Fundamental Katalog 4
FM flight model
FMS Forms Management System
FOC Faint Object Camera
FORTRAN Formula Translation (programming language, do not spell out)
FOS Faint Object Spectrograph
FOT Flight Operations Team
FOV field of view
FPA Focal Plane Assembly
FPA floating point accelerator
FPSA FPA Structure Assembly
FQR Flight Qualification Review
FRD functional requirements document
FRR Flight Readiness Review
FSK frequency shift keying
FSM First Servicing Mission
FSS Flight Servicing System
FTA fault tree analysis
FTE full time employee
FTP file transfer protocol
FU flight unit
FWHM full width at half maximum
FY fiscal year
GASP GSSS Archive Support Project
GC galactic center
GCI geocentric intertial
GDS STDN tracking station (Goldstone, CA)
GE General Electric
GEIS Generic Edited Information Set (HST image file format)
GG gravity gradient
GHRS Goddard High Resolution Spectrograph
GHz gigahertz
GIF Graphic Interchange Format
GIMP geomagnetically induced motion problem
GIO graphics input/output
GKS Graphic Kernel System
GMT Greenwich Mean Time
GO general observer (sometimes defined as "guest observer")
GPB group parameter block
GRO Gamma Ray Observatory
GRU Ground Replaceable Unit
GSC Guide Star Catalog
GSFC Goddard Space Flight Center (Greenbelt, MD)
GSOWG Ground Systems Operations Working Group
GSP General Support Pool
GSPC Guide Star Photometry Catalog
GSSS Guide Star Selection System
GST ground system test
GTO guaranteed time observer
HDOS Hughes Danbury Optical Systems (Danbury CT)
HEAO High Energy Astronomy Observatory
HGA High Gain Antenna
HIPO hierarchic input process output
HP Hewlett Packard
HPR hardware problem report
HQ headquarters
HRA High Resolution Apodizer
HR human resources
HRC High Resolution Camera
HSC Hierachical Storage Controller
HSP High Speed Photometer (removed 1993)
HRS High Resolution Spectrograph (correct use is GHRS)
HSI Host System Interface (IRAF)
HSP High Speed Photometer
HTML Hyptertext Markup Language (WWW)
HV high voltage
HVPS high voltage power supply
Hz Hertz, cycles per second
IAU International Astrophysical Union
ICCD intensified charge coupled device
ICD Interface Control Document
ICF intrinsic correlation function
ID identification
IDL Interactive Data Language (software from RSI)
IDM Intelligent Database Machine (made by Britton-Lee)
IDT image dissector tube
IDT Instrument Development Team (also Investigation Definition Team)
IEEE Institute for Electrical and Electronic Engineers
IFOV instantaneous field of view
IFOV instantaneous field of view
IFT inverse Fourier transform
IGI Interactive Graphics Interpreter (program in STSDAS)
IIPS Interactive Image Processing System
IMIO image input/output
IMSL International Mathematical and Statistical Library
I/O input/output
IP Internet Protocol
IPC inter-process communication
IPPPSSOOT file naming convention for HST data sets (not an acronym)
ips inches per second
IQL Interactive Query Language
IR infrared
IRAC International Radio Advisory Committee
IRAF Image Reduction Analysis Facility (written by NOAO)
IRAS Infrared Astronomy Satellite
IRD Interface Requirements Document
ISR instrument science report
ITF intensity transfer function
ITT International Telephone and Telegraph
IU interface unit
IUE International Ultraviolet Explorer
IUESIPS IUE Spectral Image Processing System
IV intra vehicular
IVC Institute Visiting Committee
IWG Interface Working Group
JHU The Johns Hopkins University (Baltimore, MD)
JPL Jet Propulsion Laboratory (Pasadena, CA)
JSC Johnson Space Center (Houston, TX)
K degrees Kelvin
K kilo
KB kilobytes
Kg kilogram
KHz kilohertz
Km kilometer
KPNO Kitt Peak National Observatory (Tucson, AZ)
KSC Kennedy Space Center
LAC Lockheed Aircraft Corporation
LAN local area network
LaRC Langley Research Center
LAS Laboratoire Astronomie Spatiale
LCC Launch Control Center
LDEF Long Duration Exposure Facility
LED light emitting diode
LEO low earth orbit
LeRC Lewis Research Center
LGA Low Gain Antenna
LMSC Lockheed Missile and Space Corporation
LOE level of effort
LOS line of sight
LPS Launch Processing System
LSA Large Science Aperture (GHRS)
LSF line spread function
LSG Liaison Scientists Group
LUT lookup table
LVPS low voltage power supply
LWS Long Wavelength Spectrometer
m meter
mag magnitude, unit of star flux, larger value is fainter star
MB megabyte
mas milliarcsecond
MDB multiplexed data bus
MEM Maximum Entropy Method
MeV million electron volts
MFR Manipulator Foot Restraint
MHz megahertz
MIDAS Munich Image Data Analysis System
MIL-STD military standard
MIPS million instructions per second
MIS management information system
MIT Massachusetts Institute of Technology (Cambridge MA)
MJD modified Julian date
MKO Mauna Kea Observatory
mm millimeter
MM memory module
MMI man-machine interface
MMS Module Management System
MMU Manned Maneuvering Unit
MOA memorandum of agreement
MONGO Interactive graphics software package; this is not an acronym
MOR Mission Operations Room
MOS metal oxide semiconductor
MOSES Mission Operations and Systems Engineering Support
MOSS Moving Object Support System
MOU memorandum of understanding
MOWG Mission Operations Working Group
M&P materials and processes
MPP multi-pinned phase
MPS Mission Planning System
M&R maintenance and refurbishment
MRB Material Review Board
MS master schedule
MS mission schedule
ms millisecond
MSE Milton S. Eisenhower library (JHU)
MSFC Marshall Space Flight Center (Huntsville AL)
MSC Mission Support Calibration
MSOCC Multisatellite Operations Control Center
MT moving target
MTBF mean time between failure
MTF modulation transfer function
MTL mission time line
MTR mean time to restore (also mean time to repair)
MU memory unit
mv visual magnitude
Mv absolute visual magnitude
N Newton
N/A not applicable
NAG Numerical Algorithms Groups
NAIF Navigation Ancillary Information Facility
NAS National Academy of Sciences
NASA National Aeronautics and Space Administration
NASCOM NASA communications network
NBS National Bureau of Standards (now NIST, do not use NBS)
NCAR National Center for Atmospheric Research (also their s/w)
NCC Network Control Center
NCSA National Center for Supercomputer Applications (Urbana IL)
ND neutral density
NDC Network Data Center
NEA noise equivalent angle
NEC National Electrical Code
NEMA National Electrical Manufacturers Association
NEP North Ecliptic Pole
NFS Network File System
NGP North Galactic Pole
NGT NASA Ground Terminal (White Sands NM)
NGT Next Generation Telescope
NICMOS Near-Infrared Camera and Multi-Object Spectrometer
NIST National Institute of Standards and Technology
NIU NASCOM Interface Unit
nm nanometer
NM Newton Meters
nmi nautical miles
NOAA National Oceanic and Atmospheric Administration
NOAO National Optical Astronomy Observatories (Tucson, AZ)
NOCC Network Operations Control Center
NRAO National Radio Astronomy Observatory (Greenbank, WV)
NRC National Research Council
NRL Naval Research Laboratory
NRT near real time
NSF National Science Foundation
NSI NASA Science Internet
NSP NASA Support Plan
NSSDC National Space Science Data Center (Greenbelt, MD)
NTT New Technology Telescope
NVR non-volatile residue
OAF Optical Alignment Facility
OAO Orbiting Astronomical Observatory (also OAO Corporation)
OBC on-board computer
OBP on-board processor
OCB Operational Configuration Baseline
OCC Operations Control Center
OCS Optical Control System
OCX observation comments file (from OSS)
ODB Operations Data Base
ODC other direct cost
ODF Orbit Determination Facility
ODL Observation Data Log
OFAD optical field angle distortion
OGSE optical ground support equipment
OLT Observatory Level Test
O*amp;M operations and maintenance
OMB Office of Management and Budget
OMS Observatory Monitoring System
ONR Office of Naval Research
OPB Observation Planning Branch
OPD Operations and Data Processing Division (STScI)
OPF Orbiter Processing Facility
OPO Office of Public Outreach (STScI)
OPO Operations Project Office (STScI)
OPR Operations Problem Report
OPS Operations Division (STScI)
OPUS OSS and PODPS Unified Systems
ORD Operations Requirements Document
ORI Orbit Replaceable Instrument
ORR Orbit Readiness Review
OS operating system
OSB Operations Software Branch (STScI)
OSG Observatory Support Group (STScI)
OSHA Occupational Safety and Health Act
OSS Observation Support System
OSSO Observation Science Support Office (STScI)
OST Observation Sequence Table
OTA Optical Telescope Assembly
OV orbital verification
OVIWG Orbital Verification Implementation Working Group
P&A Physics and Astronomy (building) at JHU, Bloomberg
PAD pulse amplitude discriminator
PASP Proceedings of the Astronomical Society of the Pacific
PASS POCC Application Software Support
PC Planetary Camera
PCM pulse code modulation
PCS Pointing Control System
PCT Program Coordinator Team
PDA Photon Detector Assembly
PDB project data base
PDQ PODPS Data Quality (file type)
PDR preliminary design review
PDS Photometric Data Systems (plate scanner)
P-E Perkin-Elmer Corporation
PEB Performance Evaluation Board
PEP Proposal Entry Processor
PFM Pre-Flight Module
PFR portable foot restraint
PFS percent full scale
PGPLOT FORTRAN subroutine library for plotting graphics
PI principle investigator
PM primary mirror
PM project manager
PMDB Project Management Data Base
PMT photomultiplier tube
POCC Payload Operations Control Center
PODPS Post Observation Data Processing System
PORTS Preliminary Operations Requirements and Test Support
POSS Palomar Observatory Sky Survey
PPF Payload Processing Facility
ppm parts per million
PR Problem Report
PR public relations
PRB Preliminary Review Board
PRESTO Project to Re-Engineer Space Telescope Observing (was US/PS)
PROM programmable read-only memory
PROS Post Reduction Offline Software (x-ray software from SAO)
PRR Preliminary Requirements Review
PSF point spread function
psi per square inch
PSK phase shift keying
PSL Program Support Library
P/SOS Payload/Spacecraft Operations Simulator
PSR Project Status Review
PSS Palomar Sky Survey (also POSS)
PTF Payload Test Facility
PWLA Portable Work Light Assembly
PWM pulse width modulated
Q&A qualification and acceptance
QA quality assurance
QC quality control
QE quality engineering
QE quantum efficiency
QEH quantum efficiency hysteresis
QPOE Quick Position Oriented Event (data format for PROS)
QPSK quadriture phase shift keying
QSO quasi-stellar object
QV quick visual
RA right ascension
RA research assistant
rad radian
RAM random access memory
RAS Royal Astronomical Society
RCS Readiness Control System
R&D research and development
RF radio frequency
RFI radio frequency interference
RFP request for proposal
RGA Rate Gyro Assembly
RGB red green blue
RGO Royal Greenwich Observatory
R&I receiving and inspection
RISC Reduced Instruction Set Computer (IBM)
R-L Richardson-Lucy (image restoration method)
RM retrieval mode
rms root mean square
RMS Remote Manipulator System
RMS Record Management System (VAX)
RMS Republic Management Systems, Inc.
ROE Royal Observatory Edinburgh
ROM read-only memory
RPI Rensselaer Polytechnic Institute (Rensselaer, NY)
rpm revolutions per minute
RPO Research Programs Office (STScI)
RPSS Remote Proposal Submission System
R&QA reliability and quality assurance
RS Reed-Solomon error detection
RS resource scheduler
RSB Research Support Branch (STScI)
RSDP Routine Science Data Processing
RSI Research Systems, Inc.
rss root sum squared
RSS Rotating Service Structure
RSU Rate Sensor Unit
R/T real time (preferred use is to spell out)
RTA real time activity
RTB return to brightest
RTC real time command
RTO real time operation
RTS relative time sequence
RTV room temperature vulcanizing
RWA Reaction Wheel Assembly
SA solar array
SAA South Atlantic Anomaly
SAC Solar Array Carrier
SADE-1 Solar Array Deploy Electronics-1
SAL Space Astronomy Laboratory (Univ. Wisconsin, Madison WI)
SAM small angle maneuver
SAO Smithsonian Astrophysical Observatory
SAOC SAO Catalog
SAR Software Analysis Room
S/C spacecraft (preferred use is to spell out)
SCAC Science Computing Advisory Commitee
SCARS Science Computing & Research Support Division (STScI)
SCCCB Science Computing Configuration Control Board
SCE Spacecraft Command Encoder
SCL Service Control Level
SCMS STScI Code Management System
SCO Software Change Order
SCP single color photometry
Science Data Analyst Small Computer Systems Interface
SCSI Small Computer Systems Interface
SDA Science Data Analyst Small Computer Systems Interface
SDAS Scientific Data Analysis System (replaced by STSDAS, do not use SDAS)
SDD Software Design Document
SDF Science Data Formatter
SDH science data header (file type)
SDM Secondary Deployment Mechanism
SDP science data packet
SDR System Design Review
SEA Sensor Electronics Assembly
SEB Source Evaluation Board
SEB Systems Engineering Branch
sec seconds
SEP South Ecliptic Pole
SEP Systems Engineering Plan
SEP System Enhancement Plan
SER Systems Engineering Report
SESD Science and Engineering Systems Division (STScI)
sf square foot
SGP South Galactic Pole
SHL science header line
SHP standard header packet (file type)
SI science instrument (preferred use is to spell out)
SIAF Science Instrument Aperture File
SIB Science Instrument Branch (STScI)
SIC Spacecraft Identification Code
SID Software Implementation Directive
SIDS SI Detector System
SIF Science Instrument Formatter
SIF SOGS Integration Facility
SIM simulator or simulation
SIMA Secondary Mirror Incremental Motor Actuator
SIMM standard inline memory module
SIP Software Implementation Plan
SIP SOGS-invocable procedure
SIPE Science Instrument Protective Enclosure
SIPS Spectral Image Processing System
SIRD Support Instrumentation Requirements Document
SIRTF Shuttle Infrared Telescope Facility
SITB System Integration and Testing Branch (STScI)
SJC slit jaw camera
SJR Software Justification Report
SLTV system level thermal vacuum
SM secondary mirror
SM safe mode
SMA Secondary Mirror Assembly
SMM Solar Maximum Mission
SMM science mission management
SMM Spectro-Mirror Mechanism
SMO Servicing Mission Office (STScI)
SMOV Servicing Mission Observatory Verification
SMS Science Mission Specification
S/N signal to noise ratio
S/N serial number
SNAP Structural Network Analysis Program
SOB Science Observatory Branch (STScI)
SOFA Selectable Optical Filter Assembly
SOGS Science Operations Ground System
SOW statement of work
SP sun point
SPA Solar Panel Assembly
SPAN Space Physics Analysis Network (now part of NSI)
SPB Science Planning Branch (STScI)
SPD Science Programs Division (STScI)
SPE static phase error
SPG Special Projects Group (STScI)
SPIE Society of Photo-optical Instrumentation Engineers
SPIEL Signal Processing Interactive Extensible Language
SPIF Shuttle POCC Interface Facility
SPO Sacramento Peak Observatory
SPP Subset Preprocessor (IRAF programming language)
SPR Software Problem Report
SPSO Science Program Selection Office (STScI)
SPSS Science Planning and Scheduling System
SPST Science Planning and Scheduling Team
SPYBAL spectrum Y balance
SQA software quality assurance
SQPN staggered quadriphase pseudo-random noise
SQPK staggered quadrature phase shift keying
SRB solid rocket booster
SRC Science Research Council (U.K.)
SRD Software Requirements Document
SRS Southern Reference Star
SS Star Selector (FGS)
SS System Simulator
SS Safing System
SSA Star Selector Assembly
SSA Small Science Aperture (GHRS)
SSB Science Software Branch (STScI)
SSB Space Science Board (NRC)
SSC Science Support Center (STOCC)
SSE Star Selector Encoder
SSG Science Software Group (STScI)
SSM System Support Module
SSC STEIS Steering Committee
SSD Science Support Division (STScI)
SSO Special Studies Office (STScI)
SST Software Support Team (STScI)
ST Space Telescope (preferred use is HST)
STAC Space Telescope Advisory Council
STAN Space Telescope Analysis Newsletter
STAR Space Telescope Axial Replacement (see COSTAR)
STARCAT Space Telescope Archive Catalog
STAT Space Telescope Astrometry Team
STAVF Space Telescope Assembly and Verification Facility
STDN Satellite Tracking and Data Network
ST-ECF Space Telescope European Coordinating Facility
STEIS Space Telescope Electronic Information System
STFS Space Telescope Flight Software
STIC Space Telescope Institute Council
STIF Software Test and Integration Facility
STIF Science and Technology Information Facility (Linthicum MD)
STIS Space Telescope Imaging Spectrograph
STL science trailer line
STOCC Space Telescope Operations Control Center (GSFC, Greenbelt MD)
STOL Systems Test and Operations Language
STOMS Space Telescope Observatory Management System
STR Software Test Report
STR Science Tape Recorder
STS Space Transportation System (jargon for the shuttle)
STScI Space Telescope Science Institute
STSDAS Space Telescope Science Data Analysis System (built on IRAF)
STSWG Space Telescope Science Working Group
STVSW Space Telescope Verification Software
SUNY State University of New York
SV science verification
SVD singular value decomposition
SVWG Science Verification Working Group
S/W software (preferred use is to spell out)
SWAT swift action team
TAC Time Allocation Committee
TAC telemetry and command processor (also, TAC-B for B channel)
TAG two-axis gimbal
TAR Test Authorization Request
TB thermal balance
TBD to be determined
TC test conductor
TCE Thermal Control Electronics
TCP/IP Transmission Control Protocol/Internet Protocol
TDM time division multiplexing
TDRS Tracking and Data Relay Satellite
T&E test and evaluation
TEC Thermal Electric Cooler
TEI The Education Initiative
TFMRP Transfer Function Mode Reduction Package (FGS)
TFOV target field of view
TO Texas Instruments
TIB Telescope Instrument Branch (STScI, replaced by SIB and SOB)
TIFF Tagged Image File Format
TIM Telescope Image Modeling
tm telemetry (preferred use is to spell out)
TML total mass loss
TMP Technical Management Plan
TMTE telemetry test equipment
TO target of opportunity
TOCC TDRS Operations Control Center (White Sands NM)
TOY time of year
TPI Technical Proposal Instructions
TR tape recorder
TRB Test Review Board
TTC telemetry, tracking, and command
TTOC tape table of contents
TV television
TV thermal vacuum
UAO University of Arizona Observatories
UCL University College London
UCLA University of California Los Angeles
UCSD University of California San Diego
UDL unique data log (file type)
UHF ultra high frequency
UIC user identification code (VAX)
UL Underwriters Laboratory
ULE ultra-low expansion
UMCP University of Maryland College Park
UPS uninterruptible power supply
URL uniform resource locator (WWW)
USB User Support Branch (STScI)
USNO United States Naval Observatory
UST Universal Standard Time
UT universal time
UT University of Texas
UTC coordinated universal time
UV ultraviolet
UW University of Wisconsin
V volts
VAB Vehicle Assembly Building (KSC)
VAC volts alternating current
VAP Verification and Acceptance Program
VCS Vernier Control System
VDC volts direct current
VDU video display unit
VFN virtual file name
VHF very high frequency
VLA Very Large Array (Socorro NM)
VLBI very long baseline interferometry
VLSI very large scale integration
VMC Velocity Modulating Camera
VMS Virtual Memory System
VOS Virtual Operating System (IRAF)
VPC viewport coordinates
VPF Vertical Processing Facility
VPU video processing unit
VRAM virtual random access memory
VRCS Vernier Reaction Control System
VRSD Verification Requirements and Specifications Document
W watts
WAIS Wide Area Information Server
WAN wide area network
WBS work breakdown schedule
WCS World Coordinate System
WFC Wide Field Camera
WF/PC Wide Field/Planetary Camera (instrument on HST) run by JPL
WFPC2 Wide Field Planetary Camera-2 (no slashes, hypens, or space)
WFS Wave Front Sensor
WG working group
WP work package
WSGS White Sands Ground Station
WWW World Wide Web (avoid using W3)
Z redshift
ZD zenith distance
ZOF zone of exclusion (TDRS)