Glossary

Aeolian - Noting or pertaining to sand or rock material carried or arranged by the wind.

Adsorption - The adhesion in an extremely thin layer of atoms, ions or molecules from a gas, liquid or dissolved solid to the surfaces of solid bodies or liquids with which they are in contact. This process creates a film of the adsorbate on the surface of the adsorbent.

Azimuth - An angular measurement in a spherical coordinate system. More specifically, it is the horizontal angle from a cardinal direction, most commonly north.

Cryogenic - Relating to or involving the branch of physics that deals with the production and effects of very low temperatures.

Dipoles - A pair of equal and oppositely charged or magnetized poles separated by a distance.

Diurnal Cycle - Any pattern that recurs every 24 hours as a result of one full rotation of the planet Earth around its axis

Dosimeter - A device that measures dose uptake of external ionizing radiation.

Electrostatic Potential – The amount of work needed to move a unit charge from a reference point to a specific point against an electric field.

Epithermal Neutrons - A neutron having an energy in the range immediately above the thermal range

Exosphere - The outermost region of a planet’s atmosphere.

Fiducial Marker – An object placed in the field of view of an imaging system that appears in th image produced, for use as a point of reference or a measure.

Fluidics System - Consists of a central core through which the sample fluid is injected, enclosed by an outer sheath fluid.

Fluvial - Landforms produced by the action of a river or stream.

Galactic Cosmic Rays - A type of radiation with very highly charged energy particles that originates outside our solar system and travels close to the speed of light.

General Relativity - A theory of gravity that states that instead of gravity being an invisible force that attracts objects to one another, gravity is a curving or warping of space. The more massive an object, the more it warps the space around it

Gravitomagnetism - The magnetic field produced by stars, planets, and black holes when they spin. It is directly related to the theory of general relativity in that gravitomagnetism is the twist of space and time (like a vortex) as they are pulled around a particularly massive spinning ball (e.g., a planet).

Hydrogenous - Formed or produced by water: applied to rocks formed by the action of water.

Hydroxylation - A chemical process that introduces a hydroxyl group (-OH) into an organic compound. The degree of hydroxylation refers to the number of OH groups in a molecule.

In Situ - In its natural or original position or place.

Ionizing - Any process by which electrically neutral atoms or molecules are converted to electrically charged atoms or molecules (ions) through gaining or losing electrons

Ionosphere - The layer of the earth's atmosphere that contains a high concentration of ions and free electrons and is able to reflect radio waves

Libration - The wagging or wavering of the Moon perceived by Earth-bound observers and caused by changes in their perspective. It permits an observer to see slightly different hemispheres of the surface at different times.

Magmatic Activity - The production, intrusion and extrusion of magma or lava.

Magnetometer - An instrument used for measuring magnetic forces, especially the earth's magnetism.

Magnetosphere - A region of space surrounding an astronomical object in which charged particles are affected by that object's magnetic field.

Magnetospheric Plasma - The low-density, magnetized plasma, a collection of charged particles, that flow radially outward from the Sun at supersonic speeds and pass through the Earth’s magnetic field.

Mantle - A layer inside a planetary body bounded below by a core and above by a crust. Mantles are made of rock or ices and are generally the largest and most massive layer of the planetary body.

Mass Spectrometer - An apparatus for separating isotopes, molecules, and molecular fragments according to mass. The sample is vaporized and ionized, and the ions are accelerated in an electric field and deflected by a magnetic field into a curved trajectory that gives a distinctive mass spectrum.

Mass Wasting - The movement of rock and soil down slope under the influence of gravity.

Monopole - A single electric charge or magnetic pole.

Morphology - Study of the shape, texture and distribution of materials at a surface.

Multispectral - Of or relating to two or more ranges of frequencies or wavelengths in the electromagnetic spectrum.

Neutron Flux - A measure of the intensity of neutron radiation, determined by the rate of flow of neutrons.

Oblateness - The property possessed by a round shape that is flattened at the poles.

Outgassing - The release of a gas that was dissolved, trapped, frozen, or absorbed in some material.

Pneumatic - Containing or operated by air or gas under pressure.

Pristinity - Describing the state of being in its earliest, original, or newest form. Considered unspoiled, uncorrupted, uncontaminated. (Note: lunar scientists use this term as an attribute of lunar samples; they have even developed a quantitative measurement of “pristinity” for samples turned during the Apollo-era, e.g., 88%)

Psuedo-noise - Also known as pseudorandom sequence, it’s a type of binary sequencing that can produce codes, which are an important element of certain satellite navigation systems and utilized as a method of navigation in space or “deep-space ranging.”

Regolith - A blanket of unconsolidated, loose, heterogeneous superficial deposits covering solid rock. It includes dust, broken rocks, and other related materials. (Note: It’s use in lunar science most often refers to loose material deposits on the surface of the Moon.)

Retroreflector - A device or surface that reflects radiation (usually light) back to its source with minimum scattering.

Seismicity - The occurrence or frequency of earthquakes in a region.

Seismometer - An instrument that responds to ground noises and shaking such as those caused by earthquakes, volcanic eruptions, and explosions. They are usually combined with a timing device and a recording device to form a seismograph.

Space Weathering - The changes in the optical properties of the surfaces of airless bodies caused by solar wind and cosmic ray irradiation and by micrometeoroid bombardment.

Spectrometer - A scientific instrument used to separate and measure spectral components of a physical phenomenon. Spectrometer is a broad term often used to describe instruments that measure a continuous variable of a phenomenon where the spectral components are mixed.

Spectrophotometer - A device that precisely measures electromagnetic energy at specific wavelengths of lights.

Stereo Photogrammetry - Estimating the 3D coordinates of points on an object, employing measurements made in two or more photographic images taken from different positions. The image is calculated from a collection of points obtained along an x, y, and z coordinate system.

Stratigraphy - The branch of geology concerned with the order and relative position of strata and their relationship to the geological time scale.

Thermal neutrons - Any free neutron (one that is not bound within an atomic nucleus) that has an average kinetic energy corresponding to the average energy of the particles of the ambient materials.

Thermophysical - The physical properties of materials as affected by temperatures.

Volatiles - A material that will evaporate rapidly or passing off readily in the form of vapor.

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