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JUNO JUPITER UVS 5 DERIVED DATA RECORD V1.0 (PDS)

NSSDCA ID: PSPA-01037

Availability: Archived at NSSDC, accessible from elsewhere

Description

This description was generated automatically using input from the Planetary Data System.

DATA SET OVERVIEW

The Juno Ultraviolet Spectrograph (UVS) CODMAC Level 5 Derived Data Record is a collection of single spin maps, cylindrical data cubes, auroral context maps, and average auroral maps. These data are organized, in a manner very similar to the RDR product files from which they are derived, into extensions within files formatted according to the Flexible Image Transport System (FITS) standard.

PARAMETERS

The fundamental derived parameters contained in the UVS RDR data set are the total number of calibrated photons measured at each spatial/spectral position [photons/cm^2/sr] and false-color maps of the auroral regions.

PROCESSING

These single-spin images and cylindrical data cubes are produced starting from the ¿¿¿Mike¿¿¿ RDR processed files. The Mike files along with SPICE kernels are used to produce images of the Juno UVS data on the sky as observed from Juno for each spin of the spacecraft during the perijove observing time period in each orbit of the mission, ultimately creating the DDR data products whose format is described in this document. We then produce the cylindrical data cubes using only the data recorded in the Single spin image cubes (no SPICE calls were required to assemble the cylindrical maps). Multiple versions of the output DDR products may be made available if software bugs affecting the output data are uncovered and corrected. In the event of an error whose correction alters released data, the data will be reprocessed by the revised software and made available. The auroral context false-color map products also begin with the Level 3 Mike files. They are made by adding about 80 spins of data each, using the Jupiter latitude and longitude of each photon (as provided in the Mike photon-list extension) in a 40-minute time period near closest approach. The average auroral data products are made by combining all the context false-color maps from the primary Juno mission.

DATA

The single spin image file contains the following FITS extensions: 1. Photon Map: This dataset contains the calibrated number of photons measured at each spatial/spectral position. [spatial,spatial,spectral] number of photons units=photons/cm2/sr In order to calculate the radiance this value must be divided by the integration time map and by the wavelength range in each wavelength bin [photons/s/cm-2/sr/nm]) [Extension 0 = primary FITS header and data unit (HDU)] 2. Detection Map: This dataset contains the number of detected events at each spatial/spectral position. [spatial,spatial,spectral] measured events. [Extension 1] 3. Integration Time Map: This dataset contains the total integration time in seconds within each spatial pixel of the map [spatial,spatial]. Since UVS is an imaging spectrograph the integration time at any given spatial element is the same for all wavelengths. [Extension 2] 4. Rayleigh Map: This dataset contains a brightness image (kR) of photons with wavelength between 155 and 162 nm and then multiplied by 8.1 to scale them to the equivalent total emission from all the H2 Werner and Lyman band emissions [Gerard et al., 2019]. [Extension 3] 5. Ratio Map: This dataset contains a color ratio map calculated as the radiance in photons/sec/cm2/sr between 125 and 130 nm divided by radiance in photons/sec/cm2/sr between 155 and 162 nm [Greathouse et al., 2021]. [Extension 4] 6. Latitude Image: This dataset contains the precise planetocentric latitude of Jupiter in degrees as observed by Juno UVS at the ephemeris times of each map pixel. Pixels where Juno UVS did not observe are all set to -999. [Extension 5] 7. Longitude Image: This dataset contains the precise system III west longitude of Jupiter in degrees as observed by Juno UVS at the ephemeris times of each map pixel. Pixels where Juno UVS did not observe are all set to -999. [Extension 6] 8. Latitude Nadir Image: This dataset contains the planetocentric latitudes of Jupiter in degrees within the entire image area as would have been observed by Juno UVS at the nadir time for the given spin. [Extension 7] 9. Longitude Nadir Image: This dataset contains the system III west longitude of Jupiter in degrees within the entire image area as would have been observed by Juno UVS at the nadir time for the given spin. [Extension 8] 10. Distance Image: This dataset contains the distance in km from Juno UVS to Jupiter measured from the 400 km altitude level (above 1 bar). [Extension 9] 11. Emission Angle Image: This dataset contains the emission angle (angle between Juno UVS/Jupiter vector and surface normal vector) in degrees at the 400 km altitude above the 1 bar level calculated at the precise time of the observation of each position in the map. [Extension 10] 12. Emission Angle Nadir Image: This dataset contains the emission angle (angle between Juno UVS/Jupiter vector and surface normal vector) in degrees at the 400 km altitude above the 1 bar level calculated for the entire map at the nadir time. [Extension 11] 13. Ephemeris Time Image: This dataset contains the precise ephemeris time in seconds of each measurement in the map. [Extension 12] 14. Phase Angle Image: This dataset contains the phase angle in degrees defined by the Juno UVS/Jupiter vector and the Sun/Jupiter vector at the precise time of the observation of each position in the map where UVS observed Jupiter, -999 everywhere else. [Extension 13] 15. Phase Angle Nadir Image: This dataset contains the phase angle in degrees defined by the Juno UVS/Jupiter vector and the Sun/Jupiter vector at the nadir time for all positions within the map even if it was not observed by Juno UVS. -999 if position does not intersect Jupiter. [Extension 14] 16. Slit Mask Map: This dataset contains the Values of 2 correspond to purely wide slit observations, values of 1 correspond to narrow slit only, and a combination of narrow and wide will have a value between 1 and 2. Gaps between narrow and wide slit will have value of 10. Places not observed will equal 0. [Extension 15] 17. Solar Angle Image: This dataset contains the solar incidence angle in degrees at the precise time of the observation for each pixel. -999 for any pixel not observed by UVS. [Extension 16] 18. Solar Angle Nadir Image: This dataset contains the solar incidence angle in degrees at every point in the map where Juno UVS could have measured Jupiter at the nadir time. -999 for any pixel that would not intersect Jupiter. [Extension 17] 19. Wavelength Table: This dataset contains the central wavelength of each spectral bin (nm). Wavelength bin boundaries are half way between each wavelength in this table. [Extension 18] The cylindrical data cube file contains the following FITS extensions: 1. Photon Map: This dataset contains the total calibrated number of photons measured at each spatial/spectral position. [spatial,spatial,spectral] number of photons units=photons/cm-2/sr (in order to calculate the radiance this value must be divided by the integration time map and by the wavelength range in each wavelength bin [photons/s/cm-2/sr/nm]) [Extension 0 = primary FITS header and data unit (HDU)] 2. Detection Map: This dataset contains the total number of detected events at each spatial/spectral position. [spatial,spatial,spectral] measured events. [Extension 1] 3. Integration Time Map: This dataset contains the total integration time in seconds within each spatial pixel of the map [spatial,spatial]. Since UVS is a imaging spectrograph the integration time at any given spatial element is the same for all wavelengths. [Extension 2] 4. Rayleigh Map: This dataset contains the average brightness image (kR) between 155 and 162 nm and then multiplied by 8.1 to scale them to the equivalent total emission from all the H2 Werner and Lyman band emissions [Gerard et al., 2019]. [Extension 3] 5. Ratio Map: This dataset contains the average color ratio map over the 15 spins calculated as the radiance in photons/sec/cm2/sr between 125 and 130 nm divided by radiance in photons/sec/cm2/sr between 155 and 162 nm [Greathouse et al., 2021]. [Extension 4] 6. Latitude Map: This dataset contains the planetocentric latitude in degrees of the cylindrical projection map for each pixel in the map. [Extension 5] 7. Longitude Image: This dataset contains the system III west longitude in degrees of the cylindrical projection for each pixel in the map [Extension 6] 8. Local Time Map: This dataset contains the local time of each point in the cylindrical projection at the midpoint time for the 15-spin average (the nadir time of the 7th spin) in hours (24 hour = full day). [Extension 7] 9. Solar Phase Angle Map: This dataset contains the phase angle in degrees defined by the Juno UVS/Jupiter vector and the Sun/Jupiter vector at the midpoint time of the 15-spin average (the nadir time of the 7th spin) in degrees. [Extension 8] 10. Spins Mapped: A table showing the spins included in the 15 spin average, numbered starting with the first spin of data where UVS retrieved science data. Some 15 spin averages will contain fewer than 15 spins worth of data. These 15 spin average maps were meant to be fixed in temporal size, but the Juno UVS data stream is not constant so during some periods a smaller number of spins will contain data with some spins having recorded none. The spins mapped captures this and informs the user as to which single spin maps were included in the 15 spin sum. [Extension 9] 11. Wavelength Table: This dataset contains the central wavelength of each spectral bin (nm). Wavelength bin boundaries are half way between each wavelength in this table. [Extension 10] The auroral context map files contains the following FITS extensions: 1. False Color Map: This dataset contains a false-color map of the northern and auroral regions, made using Level 3 UVS photon data acquired in a 40-minute temporal window near perijove (i.e., roughly 80 spins of data). Since auroras are continually varying, the primary purpose of the map is to provide context for the in situ particle or field measurements or remote sensing observations made by other Juno instruments. The start and stop times of the data used are provided in the header. The brightness and spectral ranges used for the RGB are chosen to accentuate auroral morphology and FUV color, and are not in physical units. The dimension of the maps are [801,801], and are 80 degrees on a side. The southern auroral region is centered on Jupiter's south pole, as if the viewer were above the aurora looking down on it. Due to the offset of the northern auroral region, the northern auroral region is centered on 80 degrees north latitude, 180 degrees W longitude (in System III coordinates). [Extension 0 = primary FITS header and data unit (HDU)] 2. Latitude Array: This dataset contains the planetocentric latitude in degrees of the false color map [Extension 1] 3. Longitude Array: This dataset contains the planetocentric system III west longitude in degrees of the false color map. For the northern map, zero longitude is toward the top, with longitudes increasing in a clockwise direction. For the southern map, zero longitude is toward the bottom, with longitudes increasing in a counterclockwise direction. [Extension 2] The average auroral map files contains the following FITS extensions: 1. False Color Map: This dataset contains a false-color map of the average northern and auroral regions, made using an average of the false color context maps for all science perijoves in which useful data were collected. The brightness and spectral ranges used for the RGB are chosen to accentuate auroral morphology and FUV color, and are not in physical units. The dimension of the maps are [801,801], and are 80 degrees on a side. The southern auroral region is centered on Jupiter's south pole, as if the viewer were above the aurora looking down on it. Due to the offset of the northern auroral region, the northern auroral region is centered on 80 degrees north latitude, 180 degrees W longitude (in System III coordinates). [Extension 0 = primary FITS header and data unit (HDU)] 2. Latitude Array: This dataset contains the planetocentric latitude in degrees of the false color map [Extension 1] 3. Longitude Array: This dataset contains the planetocentric system III west longitude in degrees of the false color map. For the northern map, zero longitude is toward the top, with longitudes increasing in a clockwise direction. For the southern map, zero longitude is toward the bottom, with longitudes increasing in a counterclockwise direction. [Extension 2] 4. Times: This dataset contains the start and stop times of the data used in each of the near-perijove context maps which were used to produce the average auroral false color map. [Extension 3]

ANCILLARY DATA

Ancillary data used in the generation of the UVS RDR data set include those calibration values required to apply instrumental corrections and calibrations to the science data as well as trajectory and pointing information for the Juno spacecraft and clock conversion tables required to enable the geometric calibration of the science data. The source of the instrumental calibration data are the UVS engineers and UVS scientists at the Southwest Research Institute in San Antonio, Texas [see GLADSTONEETAL2014 for further details], while the source of the spacecraft trajectory, pointing, and clock data are SPICE kernels provided to the UVS SOC by the Juno JSOC, having been ultimately generated by the MOC itself, the Flight Dynamics Facility (FDF) at GSFC, or the Navigation and Ancillary Information Facility (NAIF) at JPL.

SOFTWARE

Because the UVS RDR data product files adhere to version 2.1b of the FITS standard, all FITS readers up to this standard should be able to successfully read these files. There are many such FITS readers freely available in the public domain.

MEDIA/FORMAT

The UVS DDR data product files are written in FITS format, and the format of each file is described in an accompanying detached PDS label. The DDR archive itself will be electronically delivered from the Juno SOC (JSOC) to the PDS Atmospheres Node, where it will be made generally available via the World Wide Web.

These data are available on-line from the Planetary Data System (PDS) at:

https://pds-atmospheres.nmsu.edu/PDS/data/jnouvs_5001/

Alternate Names

  • JNO-J-UVS-5-DDR-V1.0

Discipline

  • Planetary Science: Atmospheres

Additional Information

Spacecraft

Experiments

Questions and comments about this data collection can be directed to: Dr. David R. Williams

 

Personnel

NameRoleOriginal AffiliationE-mail
Dr. G. Randy GladstoneData ProviderSouthwest Research Institutergladstone@swri.edu
Dr. Brad TranthamGeneral ContactSouthwest Research Institutebtrantham@swri.org
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