ion engine an experimental engine employing solar panels to accelerate charged atoms of xenon to create propulsion in space probes.
JPL Jet Propulsion Laboratory; the scientific facility and body of scientists in Pasadena, California, that oversees and maintains a space probe's mission.
Kepler launched in 2009, a spacecraft that trails Earth's orbit and searches a group of 100,000 stars in our galaxy for evidence of Earthlike or habitable planets.
lander any vessel designed to land on a planet or moon.
launch corridor a flight path.
launch window a span of time within which a satellite or probe must be launched in order to meet economic, trajectory, or orbital location requirements.
lightcraft an experimental spacecraft powered by high-intensity laser light or microwave energy beamed from the ground to the bottom of the vessel to concentrate heat and create thrust.
Lunar Prospector a space probe launched in 1998 to survey and collect data from the moon.
Magellan a probe launched in 1989 to map by radar the surface of Venus and to take measurements of the planet's gravity.
Mariner any one of various planetary probes, launched from 1962 to 1973.
Mars Direct Plan an inexpensive, speculative plan for sending humans to mars sometime around 2020.
Mars Express an orbiter and lander mission to Mars conducted by the European Space Agency. The mission failed when its landing craft, Beagle, attempted to touch down on Mars on December 25, 2003; it did not return radio signals and was presumed "lost."
Mars Global Surveyor a space probe launched in 1996 to map the planet Mars.
Mars Odyssey an orbiter that reached Mars in October of 2001 and circled the planet to collect data on radiation and surface minerals. It also served as a communications relay for the rovers Opportunity and Spirit.
Mars Pathfinder a planetary probe that landed on Mars in 1997 and radioed back photographs of a rock-strewn Martian desert.
Mars Surveyor a planetary probe launched in 1998 and 1999 in two parts to explore the south pole of Mars.
Mercury a NASA program featuring the first manned, suborbital and orbital missions, from 1961 to 1963.
microprobe a small probe launched from a larger, main probe.
Mir a Russian orbital space station, launched in 1986 and retired in 2001 when it reentered Earth's atmosphere.
modules independent subsystems on a satellite or probe.
NASA National Aeronautics and Space Administration.
NEAR Near Earth Asteroid Rendezvous; a space probe launched in 1996 to collect data on Eros, a 40-kilometer-long asteroid in the solar system's main asteroid belt.
Opportunity and Spirit two planetary rovers that landed on opposite sides of Mars in January 2004 and gathered data on climate and geology and searched for evidence of past life forms.
orbit a path followed by a spacecraft or satellite around a planet or moon, and held in place by gravitational forces.
Orion shaped like the Apollo spacecraft but three times larger, a space capsule designed to carry four astronauts to the International Space Station in 2015 and to the Moon by 2020. In an expandable form, it may carry as many as six astronauts to Mars.
Pathfinder Rover an all-terrain vehicle launched from the Mars Pathfinder to explore the surface of Mars.
payload collective term for cargo, gear, and passengers taken into space by a spacecraft.
photovoltaics see solar cells.
Pioneer any one of various lunar or planetary probes launched from 1958 to 1978.
pod any detachable component of a space vessel.
propellant any fuel providing a vessel's thrust.
reentry a satellite's reentry into Earth's atmosphere from orbit.
retro rocket an engine producing reverse thrust to slow a vessel.
rover any all-terrain vehicle launched from a lander to survey a planet's surface.
Salyut any one of seven Russian orbital space stations, launched from 1971 to 1986.
scramjet a speculative engine designed to capture massive amounts of air to burn with liquid hydrogen or other fuel, to be used to "fly" future spacecraft into orbit like jets.
scrub to cancel a launch or mission.
Skylab a U.S. orbital space station launched in 1973, and employed for scientific research; it eventually deorbited.
solar cells photovoltaic cells aligned on paddles extending out from a satellite or probe to absorb and utilize solar energy to power onboard systems.
solar probe scheduled for launch in 2007, a probe that will fly very close to the Sun to collect data on its corona and take high-resolution photographs of its surface.
Soyuz a Russian space program highlighted by the first orbital transfer of crew from one craft to another, from 1967 to 1981.
space tether connected between two space vessels, a several-miles-long line employed to "throw" one of the craft into higher orbit, by use of momentum or of electricity generated by Earth's magnetic field.
Spirit see Opportunity and Spirit.
Sputnik 1 the first artificial satellite launched into space, by the Soviets in October 1957.
Stardust a space probe launched in 1999 to collect the dust from a passing comet and bring it back to Earth.
station keeping maintaining a satellite's orbital altitude by firing onboard rockets.
subsystems any onboard instruments or modules.
telemetry the science of taking measurements from a distant point.
tracking station a ground station that tracks satellites.
trajectory flight path of a space probe.
uplink to send radio signals from Earth to a spacecraft.
Venera any one of several Russian probes studying the planet Venus.
Viking either one of two U.S. spacecraft that landed on Mars in 1976, analyzed its soil, and radioed back photographs of its terrain.
Vostok Russian space program highlighted by the first manned spaceflight and the first woman in space, 1961-1963.
Voyager either of two probes of the outer solar system, noted for radioing back spectacular photographs of Jupiter, Saturn, Uranus, and Neptune, from 1979 through the 1980s.
X-33, X-34 experimental shuttle vessels under development.
Space Shuttle
abort to stop a mission in progress, usually due to some malfunction.
airlock a chamber between a pressurized and an unpressurized compartment, or between a pressurized compartment and space.