| 1553 | Mil-Std-1553 |
| 2D | Two Dimension(al) |
| 3D | Three Dimension(al) |
| μASC | Micro Advanced Stellar Camera (a.k.a. Autonomous Star Tracker) |
| Å | Angstrom |
| ACS | Attitude Control Subsystem |
| AEC | Automatic Exposure Control |
| AECA | Arms Export Control Act |
| AETT | Ames Education Technology Team |
| AFB | Air Force Base |
| AFRL | Air Force Research Laboratory |
| A-Hr Li-Ion | Amp-Hour Lithium Ion |
| AI&T | Assembly, Integration, and Test |
| AIA | Atmospheric Imaging Assembly (part of SDO) |
| AMS | Advanced Micro Spacecraft |
| ANSI | American National Standards Institute |
| AO | Announcement of Opportunity |
| AOR | Authorized Organizational Representative |
| ARC | Ames Research Center |
| arcsec | arc second |
| AS-9100 | A Standardized Quality Management System |
| ASQC | American Society For Quality Control |
| ASSIST | Advanced Spacecraft Integration and System Testing Software |
| Assy | Assembly |
| AST | Autonomous Star Tracker (see also μASC Micro Advanced Stellar Camera) |
| ASTE | Autonomous Star Tracker Electronics (see also Data Processing Unit) |
| ASTH1 | Autonomous Star Tracker Head #1 (see also Camera Head Unit) |
| ATC | Advanced Technology Center |
| ATLO | Assembly Test and Launch Operations |
| ATST | Advanced Technology Solar Telescope |
| AU | Astronomical Unit |
| AURA | Association of Universities For Research In Astronomy |
| BAE | British Aerospace (Systems) |
| Batt | Li-Ion Battery |
| BOE | Basis of Estimate |
| BRE | Broad Reach Engineering |
| C&DH | Command & Data Handling |
| Ca II | Singly Ionized Calcium |
| CALIPSO | Cloud Aerosol LIDAR and Infrared Pathfinder Satellite Observations |
| CBE | Current Best Estimate |
| CCAg | Composite Coating On Silver (a Thermal coating) |
| CCD | Charge Coupled Device |
| CCSDS | Consultative Committee For Space Data Systems |
| CDR | Critical Design Review |
| CDS | SOHO Coronal Diagnostic Spectrometer |
| CEB | Camera Electronics Box |
| CHU | Camera Head Unit (a.k.a. ASTH, sensors of μASC) |
| CIL | Critical Items List |
| CM | Configuration Management |
| CMD | Command |
| CMOS | Complementary Metal- Oxide Semiconductor |
| CO | Concept of Operations, Carbon Monoxide |
| COBE | Cosmic Background Explorer |
| Co-I | Co-Investigator |
| cPCI | Compact Peripheral Component Interconnect [Bus] |
| CPU | Central Processing Unit |
| CRM | Continuous Risk Management |
| CSR | Concept Study Report |
| CSS | Coarse Sun Sensor |
| CSS1 | Coarse Sun Sensor #1 |
| D4D | Design for Demise |
| dB | decibel |
| DC | direct current |
| DCA | debris casualty area |
| DDTC | Director, Office of Defense Trade Controls |
| deg | degree |
| DIRBE | [Cobe] Diffuse Infrared Background Experiment |
| DL | Downlink |
| DM | Data Management |
| DN/s | Data Number/Second |
| DPU | Data Processing Unit (a.k.a. Autonomous Star Tracker Electronics) |
| DSCS | Defense Systems Communication Satellite |
| DSN | Deep Space Network |
| DSS | Digital Sun Sensor |
| DSSE | Digital Sun Sensor Electronics |
| DSSH | Digital Sun Sensor Head |
| DTU | Technical University of Denmark |
| E/PO, EPO | Education & Public Outreach |
| EA | Environmental Assessment |
| EAA | Export Administration Act |
| EAR | Export Administration Regulations |
| EB | Electronics Box |
| ECLPS | Export Import Compliance & License Processing System |
| EDCS | Export Document Control System, Enterprise Data Collaborative System |
| EEE | Electrical, Electronic, and Electromechanical |
| EEPROM | Electrically Erasable Programmable Read-Only Memory |
| EGSE | Electrical Ground Support Equipment |
| EILC | Export/Import Licensing & Compliance |
| EIN | Equipment Installation Notice, Engineering Information Network |
| EIS | Extreme Ultraviolet (EUV) Imaging Spectrometer |
| EMC | Electromagnetic Compatibility |
| EMI/EMC | Electromagnetic Interference and Electromagnetic Compatibility |
| EOL | End-of-Life |
| EPS | Electrical Power Subsystem |
| ERT | Engineering Readiness Tests |
| ESA | Electrostatic Analyzer, European Space Agency |
| E-T-E | End-To-End |
| ETU | Engineering Test Unit |
| EUV | Extreme Ultraviolet |
| EUVI | Extreme Ultraviolet Imager |
| EVM | Earned Value Management |
| EVMS | Earned-Value Management System |
| EXP | EXplorers Program office |
| F&BO | Finance & Business Operations |
| Fe | Iron |
| Fe XII | Iron (eleven times ionized) |
| FISMA | Federal Information Security Management Act |
| FITS | Flexible Image Transport Systems (a data file format) |
| FM | Flight Model |
| FMEA | Failure Modes and Effects Analysis |
| FO# | Fold Out [Page] |
| FOR | Flight Operations Review |
| FOT | Flight Operations Team |
| FOV | Field of View |
| FPP | Focal Plane Package, part of Hinode (Solar-B) |
| FTA | Fault Tree Analysis |
| FTE | Full Time Equivalent |
| FUV | Far-Ultraviolet |
| FWHM | Full Width at Half Maximum |
| FY | Fiscal Year |
| FY$ | Fiscal Year Dollar Amount |
| G&A | General and Administrative Costs |
| GB | Gigabyte (8 x 1024 x 1024 x 1024 bits, used for data storage) |
| Gbit | Gigabit (109 bits) |
| GDC4S | General Dynamics C4 Systems |
| GDS | Ground Data Systems |
| GEO | Geosynchronous Earth Orbit |
| GI | Gegenschein Imager |
| GIDEP | Government Industry Data Exchange Program |
| GN | Ground Network |
| GOES | Geostationary Operational Environmental Satellite |
| GP-B | Gravity Probe B |
| GPMC | Goddard Program Management Council |
| GPR | Goddard Procedural Requirement |
| GRACE | Gravity Recovery and Climate Experiment |
| GRAIL | NASA's Lunar Discovery Mission |
| GSE | Ground Support Equipment |
| GSFC | Goddard Space Flight Center |
| GT | Guide Telescope |
| HAO | High-Altitude Observatory |
| HAPS | Hydrazine Auxiliary Propulsion Subsystem |
| HBCU | Historically Black Colleges and Universities |
| HEB | HMI Electronics Box |
| Hinge1 | [Solar Array] Hinge #1 |
| Hinode/FPP | Hinode/Focal Plane Package |
| HK | Housekeeping |
| HMI | Helioseismic (and Vector) Magnetic Imager |
| HOPA | High-Output Paraffin Actuator (wax actuator) |
| HQ | Headquarters |
| HSB | High Speed Bus |
| HW | Hardware |
| Hz | Hertz |
| Hα | H-Alpha |
| I&T, IAT | Integration and Test |
| I/F, IF | Interface |
| IAU | Integrated Avionics Unit |
| IBIS | Interferometric Bidimensional Spectrometer |
| ICD | Interface Control Document |
| ICESat | Ice Cloud and Land Elevation Satellite |
| IDL | Interactive Data Language |
| IEB | IRIS Electronics Box |
| IEE1553 | Data Bus Standard (commonly used in science spacecraft) |
| IEEE | Institute for Electrical and Electronics Engineers |
| ILCO | International Licensing and Compliance Office |
| IMAGE | Imager For Magnetopause-To-Aurora Global Exploration |
| IMAP | IRIS Mission Archive Plan |
| IMU | Inertial Measurement Unit |
| INSITE | Investigation of The Solar Interface by Transient Exploration |
| IOC | Initial Orbit Checkout |
| IOP | IRIS Optics Package |
| IPD | Interplanetary Dust Distribution |
| IR | Infrared |
| IR&D | Independent Research and Development |
| IRAS | Infrared Astronomical Satellite |
| IRD | [Launch Vehicle] Interface Requirements Document |
| IRIS | Interface Region Imaging Spectrograph [Observatory] |
| ISS | Image Stabilization System |
| ITAR | International Traffic In Arms Regulations |
| IUA | Interface Adapter Unit |
| JPL | Jet Propulsion Laboratory |
| JSOC | SDO Joint Science Operations Center (For AIA and HMI) |
| k | kilo ( x 1000) |
| kB | kilobyte (8 x 1024 bits, used for data storage) |
| kbps | kilobits per second (1000 bits per second, used for data transmission) |
| kg | kilogram |
| km | kilometer |
| km/s | kilometer per second |
| kRad | kiloRad (unit of radiation dose) |
| KSC | Kennedy Space Center |
| L&EO | Launch and Early Operations [Phase] |
| LDPC | Low Density Parity Check (see CCSDS 131.1-O-2) |
| LED | light-emitting diode |
| LEO | Low-Earth Orbit |
| LGA | Low-Gain Antenna |
| LGAs | Low-Gain Antennas |
| LIDAR | Light Detection and Ranging/ Laser Detection and Ranging |
| Li-Ion | Lithium Ion |
| LM | Lockheed Martin |
| LMATC | Lockheed Martin Advanced Technical Center |
| LMC | Lockheed Martin Corporation |
| LMCEIO | Lockheed Martin Corporate Export/Import Office |
| LMS | License Management System |
| LMS&ES | Lockheed Martin Sensing & Exploration Systems |
| LMSAL | Lockheed Martin Solar & Astrophysics Laboratory |
| LMSSC | Lockheed Martin Space Systems Company |
| LSJU | Leland Stanford Junior University |
| LV | Launch Vehicle |
| LVDS | Low-Voltage Differential Signaling |
| LVPS | Low-Voltage Power System |
| M | million |
| m Å | milliangstrom |
| M&P | Materials & Processes |
| MA | Mission Assurance |
| MAR | Mission Assurance Requirement [Document] |
| MASC | Micro Advanced Stellar Camera (μASC) |
| MATLAB | Material Laboratory |
| MB | MegaBytes (8 x 1024 x 1024 bits, used for data storage) |
| Mbit | Megabit (1000 x 1000 bits) |
| Mbps | Megabits per second (1000 x 1000 bits/s, used for data transmission) |
| MDI | Michelson Doppler Imager, part of SOHO |
| MDRA | Mission Definition Requirements Agreement |
| MEL | Master Equipment List |
| MEROPE | Montana Earth Orbiting Pico Explorer Satellite |
| Mg | Magnesium |
| MgF2 | Magnesium Floride |
| MGM | Magnetometer |
| MGME | Magnetometer Electronics |
| MGMH | Magnetometer Sensor Head |
| MGSE | Mechanical Ground Support Equipment |
| MHD | Magnetohydrodynamics |
| MID | Mechanical Interface Control Drawing |
| MIL | Military |
| Mil-Std | Military Standard |
| min(s) | minute(s) |
| MIP | Mission Integration Plan |
| MITEX | A Defense Advanced Research Projects Agency Microsatellite |
| MK | Megakelvin |
| MLI | Multilayer Insulation (thermal blanket) |
| mm | millimeter |
| mNm | milliNewton-meter |
| MO | Mission Operations |
| MO&DA | Mission Operations and Data Analysis |
| MOAB | Multi-Operations Avionics Board |
| MOC | Mission Operations Center, Multi-Mission Operations Center |
| MOR | Mission Operations Review |
| MOS | Mission Operations System |
| MOSES | Multi-Order EUV Spectrograph Sounding Rocket |
| MPCB | Materials and Process Control Board |
| Mpixels | Megapixels (1024 x 1024 pixels) |
| MPS | Max-Planck-Institut für Sonnensystemforschung
Max Planck Institute for Solar System Research |
| ms | millisecond |
| MSP | Mars Surveyor Program |
| MSU | Montana State University |
| MSUSCI | Montana State University Student Collaboration Investigation |
| MTR | Magnetic Torque Rod |
| MTR1 | Magnetic Torque Rod #1 |
| MUCERPI | Minority University and College Education Research Partnership |
| mW | milliWatt |
| N/A | not applicable |
| NASA | National Aeronautics and Space Administration |
| NCAR | National Center For Atmospheric Research |
| NCVZ | North Continuous Viewing Zone |
| NLFFF | Nonlinear Force-Free Field |
| NOP | North Orbital Pole |
| NPD | NASA Policy Directive |
| NPOESS | National Polar-orbiting Operational Environmental Satellite System |
| NPP | NPOESS Preparatory Project |
| NPR | NASA Procedural Requirements |
| NSO | National Solar Observatory |
| NSS | NASA Safety Standard |
| NUV | Near-Ultraviolet |
| ODD | Observatory Description Document |
| OICD | Observatory Interface Control Document |
| Ops | Operation(s) |
| ORT | Operational Readiness Test |
| OSC | Orbital Sciences Corporation (provider of Pegasus ®) |
| OSIRIS | Optical, Spectroscopic, and Infrared Remote Imaging System |
| OSO-8/MXRH | Orbiting Solar Observatory 8/Mapping X-ray Heliometer |
| OSS | Office of Space Science, NASA |
| PAIP | Product Assurance Implementation Plan |
| PAO | Public Affairs Office, NASA |
| PAPI | Precision Approach Path Indicator |
| PB | power board |
| PCS | Pointing Control System |
| PDR | Preliminary Design Review |
| PER | Pre-Environmental (Test) Review |
| PI | Principal Investigator |
| PID | Proportional-Integral-Derivative Controller |
| PL | Payload |
| PL/SC | Payload/Spacecraft |
| PM | Program Manager, Primary Mirror, Primary Mounts, Protomodel |
| PM Fab | Protomodel Fabrication |
| PM/MA/SE | Program Management/Mission Analysis/System Engineering |
| PRA | Probabilistic Risk Assessment |
| ROBA-2 | Project For On-Board Autonomy |
| PRODEX | Programme De Développement d'Expériences [Scientifiques Office of ESA] |
| PSF | Point Spread Function |
| PSR | PreShip Review |
| PWR | Power |
| PZT | Piezoelectric Transducer, historically made with lead (Pb) zirconate(Zr) titanate(Ti) |
| QCM | Quartz Crystal Microbalance |
| QE | quantum efficiency |
| QS | Quiet Sun |
| Qty | quantity |
| RAD | Unit of Radiation Dose |
| RAL | Rutherford Appleton Laboratory
a.k.a Science and Technology Facilities Council (STFC) |
| RAM | Random Access Memory |
| ReqID | Requirement Identifier |
| RES | Resolution |
| RFI | Request For Information |
| RHESSI | Reuven Ramaty High-Energy Solar Spectroscopic Imager |
| RICE | Compression Scheme, developed by Robert F. Rice |
| RM | Risk Management |
| RMD | Risk Management Database |
| RMS | root mean square, Resources Management System |
| ROM | Read Only Memory, rough order of magnitude |
| ROM | Risk and Opportunity Management |
| ROMB | Risk and Opportunity Management Board |
| RSS | root sum [of the] square[s] |
| RWA | Reaction Wheel Assembly |
| RWA1 | Reaction Wheel Assembly #1 |
| RWL | Reaction Wheel |
| s | second |
| S&MA | Safety & Mission Assurance |
| SA | Solar Array |
| SACI | Solar Array & Charge-Control Interface Board |
| SAO | Smithsonian Astrophysical Observatory |
| SAP1 | Solar Array Panel #1 |
| SBA | S-band Antenna |
| SBA1 | S-band Antenna #1 |
| S-band | microwave frequency band |
| SC, S/C | Spacecraft, Student Collaboration |
| SDB | Small Disadvantaged Business |
| SDO | Solar Dynamics Observatory |
| SDO/AIA | Solar Dynamics Observatory/Atmospheric Imaging Assembly |
| SDO/HMI | Solar Dynamics Observatory/ Helioseismic (and Vector) Magnetic Imager |
| SDRAM | Synchronous Dynamic Random Access Memory |
| SE | System Engineering |
| SEC | Sun-Earth Connection |
| SEC/LWS | Sun-Earth Connection/Living with a Star |
| SECCHI | Sun-Earth Connection Coronal and Heliospheric Investigation |
| SECCHI-EUVI | SECCHI - Extreme Ultraviolet Imager |
| SEL | single-event latch-up |
| SEO | Science Enhancement Option |
| SEU | single-event upset |
| SG | Spectrograph |
| SGVM | Science Grade Vector Magnetometer |
| Si | Silicon |
| SIB | Sensor Interface Boards |
| SKC | Salish Kootenai College |
| SLAR | Supplier Limited Approval Request |
| SM | Spacecraft Manager, Structural Model |
| SMA | Safety and Mission Assurance |
| SMD | Science Mission Directorate |
| SMEX | Small Explorer |
| SMM/XRP | Solar Maximum Mission/X-Ray Polychromator |
| SOC | Science Operations Center |
| SOHO | Solar and Heliospheric Observatory |
| Solar B - FPP | Solar B - Focal Plane Package, Hinode |
| SOLIS | Synoptic Optical Long-Term Investigations of The Sun |
| SOT | Solar Optical Telescope |
| SOT-SP | Solar Optical Telescope - Spectropolarimeter |
| SOUP | Solar Optical Universal Polarimeter |
| SOW | Statement of Work |
| SP | Spectropolarimeter |
| SR&T | Science Research and Technology (NASA Grant Program) |
| SRC | Summer Research College |
| SRR | System Requirements Review |
| SS | Sun Sensor |
| SSA | Single-Service Access |
| SSEL | Space Science and Engineering Laboratory |
| SSMB | Solid State Memory Board |
| SSRD | Split-Spool Release Device [releases a solar array] |
| SSRD1 | Split-Spool Release Device #1 |
| SSTD | Space Science and Technology Department |
| ST9 | Space Technology 9 Project, NASA's New Millennium Program |
| STDN | Spaceflight Tracking and Data [Acquisition] Network |
| STEM | Science, Technology, Engineering and Math |
| STEREO | Solar TErrestrial RElations Observatory(ies) |
| STFC | Science and Technology Facilities Council
a.k.a. Rutherford Appleton Laboratory (RAL) |
| SUMER | Solar Ultraviolet Measurements of Emitted Radiation |
| SUVI | Solar Ultraviolet Imager |
| SVG | Svalbard, Norway Ground Station |
| SW | Software |
| SWAS | Submillimeter Wave Astronomy Satellite |
| SXI | Solar X-Ray Imager |
| SXT | Solar X-Ray Telescope, Yohkoh |
| TAA | Technical Assistance Agreement |
| TACSAT | Tactical Satellite |
| TACSAT2 | Tactical Satellite 2 |
| TB | Test Bed; Terrabyte (8 x 1024 x 1024 x 1024 x 1024 bits, used for data storage) |
| TDRS | Tracking and Data Relay System |
| THEMIS | Thermal Emission Imaging System |
| TIN | Taxpayer Identification Number |
| TLM | Telemetery |
| TPPI | Third-Party Proprietary Information |
| TR | Transition Region |
| TRACE | Transition Region and Coronal Explorer |
| TRL | Technology Readiness Level |
| TRR | Test Readiness Review |
| TTL | Transistor-Transistor Logic |
| TV | Thermal Vacuum |
| TV/TB | Thermal Vacuum/Thermal Balance |
| UARS | Upper Atmosphere Research Satellite |
| UCB | University of California at Berkeley |
| UK | United Kingdom |
| UK-DMC | UK Disaster Monitoring Constellation |
| UL | Uplink |
| ULE® | Ultra-Low Expansion Glass, a product of Corning Inc. |
| USN | Universal Space Network |
| UTMC | United Technologies Microelectronics Center,
A Division of Aeroflex Microelectronic Solutions |
| UV | Ultra-Violet, Ultraviolet |
| UVCS | Ultraviolet Coronal Spectrograph, SOHO |
| VAFB | Vandenberg Air Force Base |
| VFM | Vector Field Magnetometer |
| VPN | Virtual Private Network |
| W | Watt |
| WBS | Work Breakdown Structure |
| WYE | Work-Year Equivalent |
| XBA | X-band Antenna |
| X-band | microwave frequency band |
| XL | [the larger] Pegasus Faring |
| XML | Extensible Markup Language |
| XMTR | Transmitter [X-band] |
| Xponder | Transponder [S-band] |
| XRT | X-Ray Telescope |
| XSS-11 | eXperimental Satellite System 11, U.S. Air Force |
| XUV | eXtreme Ultraviolet |
| Yr | Year |
