JUNO SPK Files =========================================================================== This ``aareadme.txt'' file describes contents of the kernels/spk directory of the JUNO SPICE data server. It was last modified on August 2, 2017. Contact Chuck Acton (818-354-3869, Chuck.Acton@jpl.nasa.gov) or Boris Semenov (818-354-8136, Boris.Semenov@jpl.nasa.gov) if you have any questions regarding this data. Brief summary -------------------------------------------------------- This directory contains the SPICE SP-Kernel files for the JUNO mission, including nominal and operational spacecraft trajectory SPKs, generic planetary and satellite ephemerides SPKs, and JUNO structure locations SPKs. Naming Scheme -------------------------------------------------------- The naming scheme for cruise operations JUNO SPKs produced by NAV is: -- Reference trajectory, delivered as needed: spk_ref_YYMMDD_YYMMDD_yymmdd.bsp -- Reconstructed trajectory SPK, delivered as needed: spk_rec_YYMMDD_YYMMDD_yymmdd.bsp -- Predicted trajectory: TBD The naming scheme for orbital operations JUNO SPKs produced by NAV is: -- Reference trajectory: spk_ref_YYMMDD_YYMMDD_yymmdd.bsp -- Reconstructed trajectory covering one orbit -- apojove - 10 days to next apojove - 10 days -- delivered 3 days before apojoves: spk_rec_YYMMDD_YYMMDD_yymmdd.bsp -- Strategic trajectory delivered every 4 weeks and covering 5-6 months: spk_pre_YYMMDD_YYMMDD_yymmdd_jmxxyy.bsp -- Tactical/OTM traj delivered every 7-8 weeks and covering about 7 months: spk_pre_YYMMDD_YYMMDD_yymmdd_otmxx_p.bsp spk_pre_YYMMDD_YYMMDD_yymmdd_otmxx_f.bsp -- No-burn trajectory (for DSN, NOT delivered in nominal situations): spk_nob_YYMMDD_YYMMDD_yymmdd_otmxxPA_f.bsp where YYMMDD coverage start and STOP UTC/SCET (required); yymmdd file release date (required); Naming Scheme for Merged, Ever-growing JUNO Spacecraft SPKs The naming scheme for merged, ever-growing JUNO SPKs for orbital phases is: juno_TYPE_orbit.bsp where TYPE data type (required): rec for reconstructed pred for predicted Naming Scheme for Generic Planetary Ephemeris SPKs The naming scheme for generic planetary SPKs is: deNNN.bsp where NNN DE version (required; e.g. 421); Naming Scheme for Generic Satellite Ephemeris SPKs The naming scheme for generic satellite SPKs is: jupNNN[_EXTRA].bsp where NNN satellite ephemeris number (required; e.g. 230); EXTRA additional information token (optional; e.g. _rocks); Naming Scheme for JUNO Structure Locations SPKs The naming scheme for JUNO structure locations SPKs is: juno_struct_vNN.bsp where NN version number (required); Supplementary/Meta Information Files. -------------------------------------------------------- There are two types of supplementary/meta information files provided with the SPK files: detached label files and orbit number files. SPK Label Files. Detached label files have the same names as the corresponding SPK files with the additional extension ".lbl" appended at the end. For all files except the merged products created by NAIF, the labels do NOT have any specific structure and they contain rather ``raw'' information combined from the following sources: file SFDU label (if such was present), contents of the comment area and file summary output by the BRIEF utility program. Most of these labels are created automatically "on the fly" and are planned to be re-processed before final data archiving with the PDS. For the merged products created by NAIF, the label contains more structured and organized information including detailed description of the data sources, the way the file was created, etc. Orbit Number Files. Orbit number files are present for the corresponding merged products created by NAIF for the orbital phase of the mission. Orbit number files have the same names as the corresponding SPK file but with the extension ".bsp" replaced by ".orb". These orbit number files contain data that follow the "apoapsis-to-apoapsis" orbit numbering scheme -- with the orbit number changing at apoapsis. The information contained in the orbit number files includes the orbit number, apoapsis UTC and SCLK time, periapsis UTC time and additional information for apoapsis such as subsolar and subspacecraft longitude/latitude. Details Regarding Merged SPK File for Current Phase -------------------------------------------------------- During orbital phase of the mission, the merged SPK file(s) is updated (appended) automatically every time JUNO NAV delivers a new regular OD solution SPK file. Normally these is no label available for this(e) file(s). The corresponding orbit number file is also updated automatically once updating of its "parent" SPK file is finished.