| Question |
Answer |
| Passive Remote Sensing | The sun is the primary source of energy. Detector makes sensing data. |
| Name two types of passive remote sensing. | Solar and terrestrial. |
| Active Remote Sensing | Sensor has its own source of energy. |
| Name two types of active remote sensing. | RADAR and LIDAR |
| What role does physics play in remote sensing? | It helps us understand inputs into the system. |
| What three things happen when energy reacts with the target? | It's absorbed, transmitted, and reflected. |
| Kirkov's Law states that | absorbed + transmitted + reflected = 1 |
| At the sensor | reflection = 1 - absorbed |
| How do we take into account energy matter interactions when we collect our data? | We collect our data when these things are normalized. |
| the science and art of obtaining information about an object through analysis of data acquired by a device not in contact with the object. | Remote sensing |
| What are six advantages of remote sensing? | Improved synoptic vantage point, Provides 3D views, Capability to stop action, Provides a permanent record, enhanced spectral sensitivity, variable resolutions. |
| Name three types of information that can be sensed? | Planimetric location, topo elevation, and color. |
| What is electromagnetic energy (EMR)? | Energy flowing as a wave at the speed of light. |
| What wavelength is ultraviolet light? | 10nm - 1000nm |
| What wavelength is visible light? | 400nm - 700nm |
| What wavelength is infrared light? | 1000nm - .01cm |
| What wavelength is microwave/radar? | 1cm - 1m |
| What are two problems that are associated with the earth's atmospheres? (remote sensing) | Scattering and absorption. |
| What is an ideal remote sensing system? | A uniform energy source, a non-interfering atmosphere, unique energy / matter interactions, a super sensor, a real time data handling system, and multiple data users. |
| What are the errors associated with maps? | "DADS", distance, direction, area, and shape. |
| What are the three families of mapping projections? | Planar / Azimuthal, Conic, Cylindrical, and hybrid. |
| Map | A 2-D graphic of points, lines and polygons. That portrays spatial relationships of earth features at a reduced scale according to systematic rules. |
| What are three things a map tells you? | Geographic position, attributes and, spatial relationships. |
| What are four properties of an ideally projected map? | Conformality, equivalence, equidistant, and true direction. |
| Conformality | true shape |
| Equivalence | equal area |
| Equidistant | true distance measuring |
| True direction | thumb lines or loxidromes exist, lines of constant bearing |
| What maps are best suited to contain all ideal projected map properties? | Very large scale maps, or maps of small areas. |
| What causes map distortion? | The geometric relationships on the sphere cannot be entirely duplicated on a plane. |
| Topology | spatial relationships between mapped entities or features. |
| Graticule | a set of longitude and latitude lines. |
| Loxidrome | any straight line. |
| Conformal | true shape, cylindrical projection. |
| An example of a conformal projection is | mercader |
| Developeable | something that can be changed from 3D to 2D |
| Planar | pie shaped squares |
| Cylindracal | squares and rectangles |
| Conic | kind of like planar but different |
| Transverse | tangent to equador |
| When is distortion minimized? | when projection is tangent to the globe |
| Equivalence preserves areal relationships but not | shapes |
| When making maps you generally need to choose | ellipsoids, datums, and projection types. |
| Coordinate system | used to define location on a sphere or plane. |
| Datum | a geodetic reference system that specifies the size and shape of the earth, and the base point from which the latitude and longitude of all other points on the earth's surface are referenced. |
| Nomic | earth centered |
| DMS | Degrees Minutes Seconds (LAT/LONG) |
| LAT/LONG of (0,0) represents what place? | Greenwich Meridian (AKA Prime Meridian) -- Goes through Greenwich, England. |
| Universal Transverse Mecader | 60 zones, square grid, false origins, metric base 10 system, cuts 6 degree strips out for each zone. |
| Township | designates north / south of baseline (prime meridian) |
| Range | designates east / west of baseline (prime meridian) |
| What is included in a full legal description? | State, prime meridian name, township, range, section and subsection. |
| PLSS is what kind of mapping system? | Cartesian |
| What is the problem associated with PLSS? | It is a flat Cartesian system on a curved surface. |
| What are the three north references? | True, grid, and magnetic. |
| True North | The direction to the north pole of the axis of the earth rotation. |
| True North Baseline | A line from any point on the earth to the north pole. |
| Grid North | The grid orientation direction on a map (up). |
| Magnetic North | Utilizes earths magnetic field, is the direction a compass points to. |
| Declination | The difference between true north and magnetic north. |
| Agonic line | The line of no declination |
| Mil | 1/6400 of a circle |
| False origin | Prevents negative X and Y values. |
| Wavelength | Distance from peak to peak on SIN function. |
| Amplitude | Distance from bottom of wave trough to top of wave peak on a SIN function. |
| Frequency | the number of wave peaks passing a fixed point in unit time. |
| How are frequency and wavelength related? | Speed of Light = Wavelength X Frequency |
| What are the three regions of IR? | Near IR, Mid IR, and Thermal IR |
| What is the relationship between energy and wavelength? | The greater the wavelength the less the energy. |
| Photon | A pulse of energy |
| How is photon energy related to wavelength? | Energy in a photon is inversely proportional to its wavelength. |
| Why are energy relationships important to remote sensing? | At long wavelengths there is little energy to sense. We have to "sense" large areas to have sufficient energy. Sensing a large area results in lower spatial resolutions. In the VIS region of the EM, we can sense areas < 10M, MICRO >10M. |
| Black Body | Perfect emitters and absorbers of radiation and radiate the maximum amount of energy for their temperature. (Theoretical) |
| What is the emissivity of a gray body? | E < 1 |
| What is the emissivity of a black body? | E = 1 |
| Emissivity | The ability of a material to emit radiant energy and it's efficiency in radiating energy. |
| Planck's Law | This function represents the emitted power per unit area of emitting surface, per unit solid angle, and per unit frequency. |
| Stefan-Boltzman Law | states that the total energy radiated per unit surface area of a black body in unit time is directly proportional to the fourth power of the black body's thermodynamic temperature. |
| What are the three major atmospheric effects? | Scattering, Reflection, Absorption. |
Science Vocab 147928
