AC
alternating (electrical) current
ACE
Advanced Composition Explorer satellite
ACRIM
Active Cavity Radiometer Irradiance Monitor
Alpha
unofficial name of the International Space Station
ASCA
Advanced Satellite for Cosmology and Astrophysics
AURA
Association of Universities for Research in Astronomy
BAS
British Antarctic Survey
BBC
British Broadcasting Company
C14
carbon-14 isotope
CBC
Canadian Broadcast Company
CME
coronal mass ejection
DC
direct (electrical) current
DoD
Department of Defense (U.S.)
DOSMAP
dosimetric mapping experiment
DST
disturbance storm-time index
ERB
Earth Radiation Budget experiment
ESA
European Space Agency
EVA
extravehicular activity; also known as a space walk
FAA
Federal Aviation Administration (U.S.)
FUSE
Far Ultraviolet Spectroscopic Explorer
GIC
geomagnetically induced current
GOES
Geostationary Operational Environmental Satellites
GPS
Global Positioning System
HAO
High Altitude Observatory (U.S.)
HF
high frequency
IMF
interplanetary magnetic field
IGY
International Geophysical Year
ISS
International Space Station
ISTP
International Solar-Terrestrial Physics program
LASCO
Large-Angle Spectrometric Coronagraph
LEO
low-Earth orbit
LORAN
Long-Range Navigation system, maintained by the U.S. Coast Guard
LWS
Living with a Star program (NASA)
MHD
MagnetoHydroDynamics
MW
megawatts of electric power
NASA
National Aeronautics and Space Administration
NOAA
National Oceanic and Atmospheric Administration
NPR
National Public Radio
NRC
National Research Council (U.S.)
NRL
Naval Research Laboratory (U.S.)
NSF
National Science Foundation
rem
Roentgen equivalent man, a measure of radiation absorption by the human body
SAA
South Atlantic Anomaly
SAMPEX
Solar, Anomalous, and Magnetospheric Particle Explorer
SEC
Space Environment Center
SEU
single-event upset (in satellite computers)
SMM
Solar Maximum Mission
SOHO
Solar and Heliospheric Observatory
TRACE
NASA’s Transition Region and Coronal Explorer
UARS
Upper Atmospheric Research Satellite
UFO
unidentified flying object
USAF
United States Air Force
USGS
U.S. Geological Survey
UT
Universal Time, also known as Greenwich Mean Time
UV
ultraviolet radiation