- Industry: Aerospace
- Number of terms: 16933
- Number of blossaries: 2
- Company Profile:
The Executive Branch agency of the United States government, responsible for the nation's civilian space program and aeronautics and aerospace research.
A storage-type, electronically scanned, photoconductive, television camera tube, which, often has a response to radiation beyond the limits of the visible region. Particularly useful in space applications, as no film is required. See return beam vidicon.
Industry:Aerospace
A strip, belt, or long narrow extent of anything. Specifically refers to the ground track, or trace, followed by Landsat satellites which image a continuous swath 189 km wide.
Industry:Aerospace
A system for simultaneously recording electromagnetic radiation from the same scene in several bands from essentially the same spectral region, such as the visible or visible and near infrared. May be applied to cameras with different film/filter combinations or scanning radiometers that use disparate optics to split wavelength bands apart for viewing by several filtered detectors.
Industry:Aerospace
A system of geosynchronous communication satellites launched for the purpose of receiving and relaying data, command, and telemetry signals to and from all NASA orbiting satellites, including the Space Shuttle. The TDRSS system reduces the number of ground stations needed and simplifies the handling of a growing volume of satellite telecommunications traffic.
Industry:Aerospace
A systematic radiometric noise observed on both TM instruments on the Landsat 4 and 5 satellites. Since this SCS noise had only a finite set a values and was constant within any given scan, it was possible to correct for SCS noise during ground processing by measuring the value of the step-change in the background taken during shutter obscuration of the image at the end of each scan and inferring the SCS state for that detector and band. Since all detectors within a band switch states at the same time, the effect of SCS noise is to produce patterns of banding where different numbers of adjacent scans can be in the same state. The frequency of change of states became less and less with the time on orbit. See banding and noise.
Industry:Aerospace
A temporary storage device or circuitry which retains data for transmission between two equipment units, usually in order to compensate for differing data handling speeds of the units.
Industry:Aerospace
A unit of angle subtended by an arc of a circle equal in length to the radius of the circle.
Industry:Aerospace
A unit of measure of solid angles. Formally, it is the angle subtended at the center of the sphere by a portion of the surface whose area is equal to the square of the radius of the sphere. There are 4π steradians in a sphere.
Industry:Aerospace
A unit whose first member is a resolution cell and whose second member is the grey shade assigned to that resolution cell by a digital count. A Landsat MSS pixel represents about 0.44 hectares (1.09 acres) on the ground. One Landsat MSS frame contains about 7.36 x 106 pixels, each described by one of 64 radiance values. A Landsat ETM+ or TM pixel represents about 0.09 hectares (0.22 acres) on the ground. Each Landsat TM pixel is described by one of 256 radiance values. (All values given for DN (digital number) data only.)
Industry:Aerospace
A unitless measure of the ratio of incoming to outgoing radiation created from converting a radiometrically calibrated image to an innate characteristic of the target being observed. After removing the atmospheric component of calibrated at-satellite spectral radiance, bidirectional reflectance distribution functions (BRDFs), bidirectional reflectance, and bidirectional reflectance factors (BRF) attempt to take into account target-related differences in reflectance as a function of four sources of variability of non-Lambertian surfaces: solar zenith and azimuthal irradiance angles and sensor viewing zenith and azimuthal angles. Also see planetary albedo and reflectance.
Industry:Aerospace
