Lessons Learned from the Clementine Mission (1997)

ACE—

Advanced Composition Explorer.

ACS—

Attitude control system.

A/D—

Analog to digital.

APD—

Avalanche photodiode detector.

APL—

Applied Physics Laboratory at Johns Hopkins University.

Bitsy—

Microsatellite developed by Aero Astro Corporation for the U.S. Air Force's Phillips Laboratory.

BMDO—

Ballistic Missile Defense Organization: The arm of the U.S. Department of Defense charged with developing missile-defense systems. BMDO was formerly known as SDIO.

Brilliant Eyes—

A generic name for a family of small, space-based missile early-warning satellites.

Brilliant Pebbles—

A generic name for a small, space-based ICBM interceptor with a nonexplosive warhead.

Cassini—

A very large Saturn orbiter scheduled for launch by NASA in October 1997.

CCD—

Charge-coupled device: An electronic detector used for low-light-level imaging and astronomical observations. CCDs have now replaced photographic emulsions for sensing visible light in most space science applications.

CNES—

Centre National d'Etudes Spatiales: The French National Space Agency.

Discovery—

A continuing line in NASA's budget dedicated to small planetary missions characterized by a 3-year development schedule and a budget cap of $150 million (FY 1992). Mars Pathfinder and Near-Earth Asteroid Rendezvous (NEAR), the first two Discovery missions, were granted new starts in NASA's FY 1994 budget. Two additional missions, Lunar Prospector and Stardust, were competitively selected for new starts in NASA's FY 1995 and 1996 budgets, respectively.

DOD—

Department of Defense.

DRAM—

Dynamic random access memory.

Earth Probes—

A series of small Earth observation satellites including TOMS and TRMM.

Earth System Science Pathfinder—

A line of small Earth observation satellites characterized by a 36-month

development schedule and capped life-cycle costs. The first two such missions, the Vegetation Canopy Lidar and the Gravity Recovery and Climate Explorer, are scheduled for launch in 2000 and 2001, respectively.

e/bit—

electrons per bit.

GaAs/Ge—

Gallium arsenide/germanium: Semiconductors used in the construction of solar arrays.

GFO—

Geosat Follow-On mission.

HgCdTe—

A type of infrared array detector composed of an alloy of mercury (Hg), cadmium (Cd), and tellurium (Te).

ICBM—

Intercontinental ballistic missile.

InSb—

A type of focal-plane array used for sensing near-infrared radiation composed of indium (In) and antimony (Sb).

IPDT—

Integrated product development team.

IUS—

Inertial Upper Stage.

JPL—

Jet Propulsion Laboratory.

LEAP—

Lightweight Exo-Atmospheric Projectile.

Lidar—

Light identification, detection, and ranging.

LMLV—

Lockheed Martin Launch Vehicle.

LMLV2—

Second-generation Lockheed Martin Launch Vehicle.

LOSAT-X—

SDIO experimental satellite.

Lunar Prospector—

NASA's third Discovery mission, a small lunar orbiter scheduled for launch in October 1997 (see Table 3.1).

Magellan—

The first Shuttle-launched interplanetary spacecraft. Following its launch from Atlantis in 1989, Magellan mapped almost all of Venus's surface using synthetic aperture radar and conducted measurements of the planet's gravitational field.

Mars Observer—

The first and last of NASA's Planetary Observer series. It was launched in 1992 and was lost shortly before entering orbit around Mars in 1993.

Mars Pathfinder—

Formerly known as the Mars Environmental Survey (MESUR) Pathfinder, this spacecraft is one of the first two Discovery missions and was launched in December 1996. The mission consists of a lander and a surface rover, ''Sojourner" (see Table 3.1).

Mars Surveyor—

A continuing line in NASA' s budget dedicated to the launch of two small- to intermediate-sized Mars missions at every launch opportunity (every 26 months) between 1996 and 2005. The first Surveyor mission, Mars Global Surveyor, was launched in November 1996 and is expected to arrive at Mars in September 1997.

MGS—

Mars Global Surveyor: The first of NASA's Mars Surveyor missions.

MidEx—

Mid-sized Explorer: A continuing line in NASA's budget dedicated to low-cost (<<$70 million) missions in space physics and astrophysics.

Milstar Military Star:—

A series of large military communications satellites.

MIPS—

Million instructions per second.

MISR—

Multi-Angle Imagery Spectral Radiometer.

MMH—

Monomethyl hydrazine.

MSTI—

Miniature Seeker Technology Integration.

NEAR—

Near-Earth Asteroid Rendezvous: One of NASA's first two Discovery missions, it was launched in February 1996 and will rendezvous with 433 Eros in January 1999 (see Table 3.1).

NRL—

Naval Research Laboratory.

OSS—

NASA's Office of Space Science.

PI—

Principal investigator.

RISC—

Reduced instruction set computer.

SAPPHIRE—

Stanford Audio-Phonic Photographic Infrared Experiment. A graduate-student project at Stanford University designed to space-qualify a micromachined infrared sensor developed at JPL.

SBIR—

Space-based Infrared: A series of small satellites designed to provide early warning of the launch of tactical and intercontinental ballistic missiles.

SDIO

—Strategic Defense Initiative Organization: The predecessor of BMDO.

STRV—

Space Test Research Vehicle: A series of microsatellites sponsored by the U.K.'s Defense Research Agency to investigate the effects of the space environment on spacecraft electronics.

TAOS—

Technology Autonomous Operational Satellite.

THAAD—

Theater High-Altitude Area Defense: A long-range, ground-to-air missile system.

TOMS—

Total Ozone Mapping Spectrometer: A small NASA spacecraft launched in 1996 and designed to make global measurements of atmospheric ozone.

TRACE—

Transition Region and Coronal Explorer: A mission in NASA's series of Small Explorers designed to study the Sun's photosphere and corona. Launch is scheduled for September 1997.

TRMM—

Tropical Rainfall Mapping Mission: A joint NASA-Japanese mission designed to measure global tropical rainfall, scheduled for launch in the fall of 1997.

USAF—

United States Air Force.