EDUCATION AND PUBLIC OUTREACH PROGRAM
a NASA-funded program dedicated to public education
at The Ohio State University Mapping & GIS Laboratory
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accuracy: degree of conformity with a standard. Accuracy relates to the quality of a result and is distinguished from precision which relates to the quality of the operation by which the result is obtained.
ALS: airborne laser scanner
anaglyph: a moving or still picture consisting of two slightly different perspectives of the same subject in contrasting colors that are superimposed on each other, producing a three-dimensional effect when viewed through two correspondingly colored filters.
azimuth: horizontal direction reckoned clockwise from the meridian plane. The azimuth of a point on the celestial sphere is defined as the angular distance measured towards the east, from north, along the astronomical horizon to the intersection of the great circle passing through the point and the astronomical zenith with the astronomical horizon. See http://www.heavens-above.com/gloss.asp?term=azimuthbathymetry: science of
measuring water depths (usually in the ocean) to determine bottom
topography.
cadastral map: map showing
the boundaries of subdivisions of land, often with the bearings and
lengths
thereof and the areas of individual tracts, for purposes of describing
and
recording ownership. It may also show culture, drainage, and other
features
relating to land use and value. See plat
Cartesian coordinate system: A coordinate system in which the coordinates of a point are its distances from a set of perpendicular lines that intersect at an origin, such as two lines in a plane or three in space.
Cartesian mapping: mapping based on the Cartesian product, whereby a set of all pairs of elements (x, y) that can be constructed from given sets, X and Y, such that x belongs to X and y to Y. A coordinate system in which the location of a point in n-dimensional space is defined by distances from the point to the reference plane. Distances are measured parallel to the planes intersecting a given reference plane.
cartography: science and art of making maps and charts.
clinometric map: see slope map
contour: imaginary line on ground, all points of which are at the same elevation above or below a specific datum.
coordinate systems: see http://www.colorado.edu/geography/gcraft/notes/coordsys/coordsys.html
crater: a bowl-shaped depression
formed by the impact of a meteorite or a bowl-shaped geological
formation at the top of a volcano
digitization, map: conversion of map data from graphic to digital form.
Doppler: a "Doppler" radar has the capability of measuring some information about winds (on top of the usual echo strength all radars measure) by using the Doppler Effect. See http://www.radar.mcgill.ca/define_doppler.html
EDM: electronic distance measuring (EDM) device: Instruments that measure the phase difference between transmitted and reflected or retransmitted electromagnetic waves of known frequency, or that measure the round-trip transit time of a pulsed signal, from which distance is computed.
ejecta blanket: continuous ejecta deposit around an impact crater, i.e., material deposited around an impact crater during excavation of the crater.
electromagnetic: the energy that radiates from all things in nature and from man-made electronic systems. It includes cosmic rays, gamma rays, x-rays, ultraviolet light, visible light, infrared light, radar, microwaves, TV, radio, cellphones and all electronic transmission systems. Electromagnetic radiation is made up of electric and magnetic fields that move at right angles to each other at the speed of light.
electromagnetic spectrum: see http://imagine.gsfc.nasa.gov/docs/science/know_l1/emspectrum.html
elevation: vertical distance of a point above or below a reference surface or datum.
error, positioning or localization: the divergence of reported location from actual location.
geodetic science: the science of geodesy
geographical datums: see http://www.colorado.edu/geography/gcraft/notes/datum/datum.html
Geoinformation Science: incorporates the scientific disciplines of surveying, spatial analysis, geostatistics, geographic information systems, cartography, and visualization.
geoid: figure of the Earth visualized as a mean sea level surface extended continuously through the continents. It is a theoretically continuous surface that is perpendicular at every point to the direction of gravity (the plumb line).
geomatics: geomatics is a field of activities which, using a systemic approach, integrates all the means used to acquire and manage spatial data required as part of scientific, administrative, legal and technical operations involved in the process of the production and management of spatial information.
geomatics engineering: geomatics engineering focuses on spatial information, or information that has a location. Geomatics is the science that knits all the spatial information disciplines together, and geomatics engineering is developing the science and crating new uses for the technology developed.
georeferencing: establishing a relationship between image coordinates and known real-world coordinates. Assigning coordinates from a known reference system, such as latitude/logitude, UTM, or British National Grid, to the page coordinates of a raster(image) or planar map. Georeferencing allows data to be viewed, queried and analysed with other geographical data.
GIS, geographical information systems: These systems allow geographers to collate and analyze information far more readily than is possible with traditional research techniques. As will be noted below, GIS can be viewed as an integrating technology insofar as it draws upon and extends techniques that geographers have long used to analyze natural and social systems. A computerized database management system used for the capture, conversion, storage, retrieval, analysis, and display of spatial data.
global coordinate system: coordinate system based on a global scale
GPS, Global Positioning System: The GPS system uses external satellites to detect the current position. See http://www.colorado.edu/geography/gcraft/notes/gps/gps.html
grid: network of uniformly spaced parallel lines intersecting at right angles. When superimposed on a map, it usually carries the name of the projection used for the map- that is, Lambert grid, transverse Mercator grid, universal transverse Mercator grid.
gyroscope: a device consisting of a spinning mass, typically a disk or wheel, mounted on a base so that its axis can turn freely in one or more directions and thereby maintain its orientation regardless of any movement of the base. Unaffected by magnetic variations, its spinning axis, when brought in line with the north-south axis of the earth, provides an accurate line of reference for navigation.
hazcam: Hazard Avoidance Camera,
located on the front and rear of the MER 2003 rovers
image matching: the linking of the two images from a stereo pair into one image through overlapping based on matching points, or identical points identified in each image.
imagery: visible representation of objects and (or) phenomena as sensed or detected by cameras, infrared and multispectral scanners, radar, and photometers. Recording may be on photographic emulsion (directly as in a camera or indirectly after being first recorded on magnetic tape as an electrical signal) or on magnetic tape for subsequent conversion and display on a cathode ray tube.
IMU, Inertial Measurement Unit: An Inertial Measurement Unit is a closed system that is used to detect attitude location and motion. Typically installed on aircraft or UAVs, it normally uses a combination of accelerometers and angular rate sensors (GYROs) to track how the craft is moving and where it is. Typically, an IMU detects the current acceleration and rate of change in attitude (i.e. roll, pitch and yaw rates) and then sums them to find the total change from the initial position. An IMU stands in contrast to the GPS system, which uses external satellites to detect the current position. See http://en.wikipedia.org/wiki/Inertial_Measurement_Unit Or, a pit to cook your luau, see http://www.alohafriendsluau.com/imu.html
infrared scanner (thermal mapper): instrument that detects infrared radiation and converts the detected energy to an electrical signal for recording on photographic film or magnetic tape.
interest points: e.g., corners and line intersections)
lander: a space vehicle designed to
land on a celestial body, such as the moon or a planet.
local coordinate system: Cartesian
coordinates in a non-Earth (non-georeferenced) coordinate system.
Contrast to global coordiante system
map projections: see http://www.colorado.edu/geography/gcraft/notes/mapproj/mapproj.html
margin of error: a measure of
how "precise" are some collection of data
MI (Microscopic Imager): is a combination of a microscope and a camera. It produces extreme close-up views of rocks and soils examined by other instruments on the instrument arm of each rover, providing contextual information for the interpretation of mineral and element composition data.
monoscopic: pertaining to the observation of a single photograph or other view.
mosaic: assembly of aerial photographs whose edges usually have been torn or cut selectively and matched to the imagery on adjoining photographs to form a continuous representation of a portion of the Earth's surface.
multispectral scanner
(MSS): device for sensing radian energy in several channels of
the
electromagnetic spectrum.
National Geodetic Vertical Datum of 1929: reference surface established by the U.S. Coast and Geodetic Survey in 1929 as the datum to which relief features and elevation data are referenced in the conterminous United States; formerly called "mean sea level 1929."
National Map Accuracy Standards: specifications promulgated by the U.S. Office of Management and Budget to govern accuracy of topographic and other maps produced by Federal Agencies.
navcam: navigation camera
odometry: measurement of distances by the odometer, which is a instrument attached to a vehicle or connected to the wheel of a vehicle, which measures the distance traversed.
Opportunity: Mer B The second rover of the MER 2003 Mission. It landed in Gusev Crater.
orbiter: a spacecraft whose purpose is to orbit around an object like a planet or a satellite. In other words, a satellite.
orthophoto: a stereoscopic aerial picture. Digital imagery in which distortion from the camera angle and topography have been removed, thus equalizing the distances represented on the image.
orthophotograph: photograph having the properties of an orthographic projection. It is derived from a conventional perspective photograph by simple or differential rectification so that image displacements caused by camera tilt and terrain relief are removed.
orthophotographic map: map produced by assembling orthophotographs at a specified uniform scale in a map format.
orthophotomap: orthophotographic map with contours and cartographic treatment, presented in a standard format, and related to standard reference systems.
orthophotoquad: monocolor orthophotographic map presented in a standard quadrangle format and related to standard reference systems. It has no contours and little or cartographic treatment.
overlay: printing or
drawing on a transparent or translucent medium intended to be placed in
register on a map or other graphic and which shows details not
appearing or
requiring special emphasis on the base material.
pan: to move across an image as if
moving across a panorama; a tool of imaging software
panorama: a 360-degree photograph or digital image. Created by linking together multiple images taken at regular intervals. An unbroken view of an entire surrounding area.
parallax: the difference between where your right eye sees a point, and how your left eye sees it.
pixel: commonly, the basic unit of the composition of an image on a television screen, computer monitor, or similar display. A pixel (a contraction of picture element) is any of the many tiny dots that make up the representation of bitmap images (i.e., patterns of dots) which are stored in a computer's memory or shown on a display monitor. The number of pixels in an image is called the resolution. In photogrammetry, the basic unit of measurement in a photograph or digital image.
photogrammetrist: scientist certified in the science of photogrammetry
photogrammetry: science or art of obtaining reliable measurements or information from photographs or other sensing systems.
planimetry: plan details of a map - those having no indication of relief or contour.
planimetric map: map that presents only the horizontal positions for features represented. Distinguished from a topographic map by the omission of relief in measurable form. The features usually shown on a planimetric map include rivers, lakes, and seas; mountains, valleys, and plains; forests, and prairies; cities, farms transportation routes, and public utility facilities; and political and private boundary lines. A planimetric map intended for special use may present only those features essential to the purpose to be served.RAT: Remote Abrasion Tool carried by the MER 2003 rovers.
raster: one of the two major methods of GIS data identification and storage. Pixels in a grid are characterized as either having or not having a particular quality. In imagery, a raster image file is generally defined to be a rectangular array of regularly sampled values, known as pixels. Each pixel (picture element) has one or more numbers associated with it, generally specifying a color which the pixel should be displayed in. These are like bitmap images. See also vector.
rectification, differential: the process of scanning and re-projecting a photograph onto a horizontal plane in differential elements to remove displacements caused by tilt and relief. The process may be accomplished by any one of a number of instruments developed specifically for the purpose.
rectification, simple: projection of an aerial photograph (mathematically, graphically, or photographically) from its plane onto a horizontal plane by translation, rotation, and (or) scale change to remove displacement due to tilt of the camera.
relief: elevations and depressions of the land or sea bottom.
remote sensing: process of
detecting and (or) monitoring chemical or physical properties of an
area by measuring
its reflected and emitted radiation. F.F. Sabins in his book "Remote
sensing: principles and interpretation" defines it as follows: "Remote
Sensing is the science of
acquiring, processing and interpreting images that record the
interaction
between electromagnetic energy and matter.
representational fraction:
scale of a map or chart expressed as a fraction or ratio that relates
unit
distance on the map to distance measured in the same unit on the ground.
resolution: the number of pixels per unit.
rover: roving robot, used
in Mars exploration missions.
satellite: the term for a body in orbit around a planet.
scale: the ratio of the distance on a map, photograph, or image to the corresponding image on the ground, all expressed in the same units.
Spirit: Mer A. The first rover of the MER 2003 Mission. It landed in Meridiana Planum.
stereo camera: a stereo camera is a type of camera with two or more lenses. This allows the camera to simulate human binocular vision, and therefore gives it the ability to capture 3-D Images.
stereo pair, stereopair: a pair of images taken by a stereo camera.
slope map (clinometric map): map showing the degree of steepness of the Earth's surface by the use of various colors or shading for critical ranges of slope.
sensor: technical means, usually electronic, to extend man's natural senses by detecting emitted or reflected energy. The energy may be nuclear, electromagnetic (including the visible and invisible portions of the spectrum), chemical, biological, thermal, or mechanical
spheroid: mathematical figure closely approaching the geoid in form and size and used as a surface of reference for geodetic surveys. A reference spheroid or ellipsoid is a spheroid determined by revolving an ellipse about its shorter (polar) axis and used as a base for geodetic surveys of a large section of the Earth (such as the Clarke spheroid of 1866 which is used for geodetic surveys in the United States).
spot elevation: point on a map or chart whose height above a specified datum is noted, usually by a dot or a small sawbuck and elevation value. Elevations are shown, on a selective basis, for road forks and intersections, grade crossings summit of hills, mountain
state plane coordinate system: coordinate systems established by the U.S. Coast and Geodetic Survey (now the National Ocean Survey), usually one for each state, for use in defining positions of points in terms of plane rectangular (x, y) coordinates.
stereoscopic: pertaining to the use of binocular vision for observation of a pair of overlapping photographs or other perspective views, giving impression of depth.
spatial: a generic term
used to reference the mathematical concept of n-dimensional data. Data
that is
referenced by its location in n-dimensional space. The position of
spatial data
is described by multiple values.
tiepoint: a tie point, or match point, is the measurement of the location of single feature across two overlapping images, with the purpose of tying two or more images together. See http://isis.astrogeology.usgs.gov/Isis2/isis-bin//viking_geodesy.cgi
traverse: to travel across, used to indicate the path of the rover as it travels between waypoints.
3-D: three-dimensional: having measurable dimensions of height, width, and length.
thermal mapper: see infrared scanner
topographic map: map that presents the horizontal and vertical positions of the features represented; distinguished from a planimetric map by the addition of relief in measurable form.
topography: configuration (relief) of the land surface; the graphic delineation or portrayal of that configuration in map form, as by contour lines; in oceanography the term is applied to a surface such as the sea bottom or surface of given characteristics within the water mass.
traverse: sequence of lengths and directions of lines connecting a series of stations, obtained from field measurements, and used in determining positions of the stations.
triangulation: method of extending
horizontal position on the surface of the Earth by measuring the angles
of
triangles and the included sides of selected triangles.
Universal Transverse Mercator (UTM) grid: Military grid system based on the transverse Mercator projection, applied to maps of the Earth's surface extending from the Equator to 84 Degrees north and 80 degrees south latitudes.
vector: One of the two major
methods of GIS data identification and storage. Vector graphics is the
creation of digital images through a sequence of commands or mathematical statements that place
lines and shapes in a given two-dimensional or three-dimensional space.
See also raster.
virtual:
Virtual
(Adjective) Pronunciation: ['vêr-chu-wêl]
1: Existing in essence though not in fact, having the power or effect
of some object
or position in the absence of the actual object or position.
visible: the part of the
electromagnetic spectrum that can be seen by the human eye
x-axis: One of
three axes
in a three-dimensional Cartesian coordinate system. Represents length.
y-axis: One of
three axes
in a three-dimensional Cartesian coordinate system. Represents depth.
zoom: a tool of imaging software
Map Terms: http://www.graphicmaps.com/mapterms.htm
Definitions of Geomatics: http://surveying.mentabolism.org/geomatic.htm
Glossary of Coastal Terms: http://www.csc.noaa.gov/text/glossary.html