The Ultraviolet Imager (UVI) is a small camera that detected and produced images of the ultraviolet light of the aurora, day and night. Using any of five specially designed filters the UVI camera imaged an eight degree circular field of view. Images are generated once every 37 seconds with a nominal pixel angular resolution of 0.036 degrees.

Instrument Functional Description: The VIS Instrument is a Set of three Low Light Level Cameras. Two of these Cameras share primary and some secondary Optics and are designed to provide Images of the Nighttime Auroral Oval at Visible Wavelengths. A Third Camera is used to monitor the Directions of the Fields-of-View of the Auroral Cameras with respect to the sunlit Earth and return Global Images of the Auroral Oval at Ultraviolet Wavelengths. The VIS Instrumentation produces an Auroral Image of 256 × 256 Pixels approximately every 24 s dependent on the Integration Time and Filter selected. The Fields-of-View of the two Nighttime Auroral Cameras are 5.6 × 6.3° and 2.8 × 3.3° for the Low and Medium Resolution Cameras, respectively. The Medium Resolution Camera was never activated. One or more Earth Camera Images of 256 × 256 Pixels are produced every 5 min, depending on the commanded Mode. The Field-of-View of the Earth Camera is approximately 20 × 20°. See: http://vis.physics.uiowa.edu/vis/vis_description/vis_description.htmlx Reference: Frank, L.A., J.B. Sigwarth, J.D. Craven, J.P. Cravens, J.S. Dolan, M.R. Dvorsky, J.D. Harvey, P.K. Hardebeck, and D. Muller, The Visible Imaging System (VIS) for the Polar Spacecraft, Space Science Review, Vol. 71, pp. 297-328, 1995. Data Set Description: The VIS Earth Camera Data Set comprises all Earth Camera Images for the selected Time Period. Full Coordinate Information is included for Viewer Orientation. In addition, a Rotation Matrix and a Table of Distortion-correcting Look Direction Unit Vectors are provided for the Purpose of calculating Coordinates for every Pixel. To facilitate viewing of the Images, a Mapping of Pixel Value to a recommended Color Table based on the Characteristics of the selected Filter will be included with each Image. A Relative Intensity Scale is provided through an Uncompressed Count Table. Approximate Intensity Levels in kiloRayleighs are given in an Intensity Table. For detailed Information on Intensities, see Sensitivities_and_Intensities.txt at https://cdaweb.gsfc.nasa.gov/Polar_VIS_docs/SENSITIVITIES_AND_INTENSITIES.TXT. Supporting Software is available at: http://vis.physics.uiowa.edu/vis/software/ Included is an IDL Program that displays the Images with the recommended Color Bar, provides approximate Intensities, Coordinate Data for each Pixel, and includes multiple Options for Image Manipulation.

Instrument Functional Description: The VIS Instrument is a Set of three Low Light Level Cameras. Two of these Cameras share primary and some secondary Optics and are designed to provide Images of the Nighttime Auroral Oval at Visible Wavelengths. A Third Camera is used to monitor the Directions of the Fields-of-View of the Auroral Cameras with respect to the sunlit Earth and return Global Images of the Auroral Oval at Ultraviolet Wavelengths. The VIS Instrumentation produces an Auroral Image of 256 × 256 Pixels approximately every 24 s dependent on the Integration Time and Filter selected. The Fields-of-View of the two Nighttime Auroral Cameras are 5.6 × 6.3° and 2.8 × 3.3° for the Low and Medium Resolution Cameras, respectively. The Medium Resolution Camera was never activated. One or more Earth Camera Images of 256 × 256 Pixels are produced every 5 min, depending on the commanded Mode. The Field-of-View of the Earth Camera is approximately 20 × 20°. See: http://vis.physics.uiowa.edu/vis/vis_description/vis_description.htmlx Reference: Frank, L.A., J.B. Sigwarth, J.D. Craven, J.P. Cravens, J.S. Dolan, M.R. Dvorsky, J.D. Harvey, P.K. Hardebeck, and D. Muller, The Visible Imaging System (VIS) for the Polar Spacecraft, Space Science Review, Vol. 71, pp. 297-328, 1995. Data Set Description: The VIS Earth Camera Data Set comprises all Earth Camera Images for the selected Time Period. Full Coordinate Information is included for Viewer Orientation. In addition, a Rotation Matrix and a Table of Distortion-correcting Look Direction Unit Vectors are provided for the Purpose of calculating Coordinates for every Pixel. To facilitate viewing of the Images, a Mapping of Pixel Value to a recommended Color Table based on the Characteristics of the selected Filter will be included with each Image. A Relative Intensity Scale is provided through an Uncompressed Count Table. Approximate Intensity Levels in kiloRayleighs are given in an Intensity Table. For detailed Information on Intensities, see Sensitivities_and_Intensities.txt at https://cdaweb.gsfc.nasa.gov/Polar_VIS_docs/SENSITIVITIES_AND_INTENSITIES.TXT. Supporting Software is available at: http://vis.physics.uiowa.edu/vis/software/ Included is an IDL Program that displays the Images with the recommended Color Bar, provides approximate Intensities, Coordinate Data for each Pixel, and includes multiple Options for Image Manipulation.

The Ultraviolet Imaging Telescope (UIT) Near-UV Bright Objects Catalog is a photometric catalog of 2244 objects detected by the UIT in the near-ultraviolet (NUV; 1650A-16ergs/s/cm2/A, but the survey is not complete to this level. Optical catalogs were used to cross identify sources and derive near-UV to Johnson V colors. A majority of the objects (88%) do indeed have proposed optical identifications from catalogs, and most are stars. The authors' purpose in creating the catalog was to form a database useful for identifying very blue objects and for performing Galactic UV stellar population studies. This database was created by the HEASARC in November 2000 based on a machine-readable version obtained from the CDS (Catalog J/ApJS/104/287). This is a service provided by NASA HEASARC .

The International Ultraviolet Explorer (IUE) performed spectrophotometry at high (0.1-0.3 Å) and low (6-7 Å) resolution between 1150 Å and 3200 Å. The data cover a dynamic range of approximately 17 astronomical magnitudes: -2 to 10 for high dispersion; -2 and 14.9 for low dispersion. Over 104,000 ultraviolet spectra were obtained with IUE between January 26, 1978, and September 30, 1996.

This describes the data produce for ICON EUV Daytime O+ (DP 2.6), which is in NetCDF4 format. These files are named ICON_L2-6_EUV_YYYY-MM-DD_vXXrZZ.NC, where YYYY-MM-DD is the year month day and VXX shows the version number and rZZ shows the revision number of this file. Each individual file nominally contains 1 day (24 hours) of data. The L2 EUV Daytime files are produced from the L1 EUV files, and their primary data product is the O+ profile derived from a retrieval that is detailed in a paper: https://doi.org/10.1007/s11214-017-0385-1. In addition, many other parameters and geophysical data products are included in the file. The data are identified in one of 3 var_types: data – which contains the primary data product; support data – which contains parameters used in the retrieval such as geometry etc. that may also be useful in any analysis of this data; and ignore_data – which are recorded for debugging purposes and should not be used for publication without detailed discussion with the ICON team. The dimensions of the data also indicate its type. For example, anything with epoch as a dimension means there is 1 value corresponding to each instrument exposure. Anything with dimension Input_data corresponds to the input data, passed from Level 1. Anything with a dimension of model refers to the forward model parameters used as part of the inversion. Anything with dimension altitude corresponds to the altitude grid used for the inverted parameters.