MRO SPK files.
===========================================================================
This ``aareadme.txt'' file describes contents of the kernels/spk
directory of the MRO SPICE data server. It was last modified on July
24, 2007. 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 MRO
spacecraft. The following files are present in this directory. (Only
file names are shown; the file name extensions of the binary SPK files
are always ".bsp"):
Ever-growing merged SPK files:
mro_psp_rec Ever-growing "up-to-date" reconstructed PSP
trajectory SPK file regularly updated by
append-merging reconstructed PSP OD solution
SPK files from MRO NAV. The coverage of this
file extends through the end of the coverage
the last delivered regular reconstructed PSP
OD solution SPK (spk_psp_rec*_r-* SPK files.)
mro_psp Ever-growing "up-to-date" predicted PSP
trajectory SPK file regularly updated by
append-merging predicted PSP OD solution SPK
files from MRO NAV. The coverage of this file
extends through the end of the coverage the
last delivered regular predicted PSP OD
solution SPK (spk_psp_rec*_p-* SPK files.)
Regularly delivered SPK files:
spk_psp_rec*_r-* Regular reconstructed PSP OD solution SPK
produced by MRO NAV.
spk_psp_rec*_p-* Regular predicted PSP OD solution SPK
produced by MRO NAV.
Merged SPK files for earlier mission phases:
mro_cruise Merged SPK covering the whole cruise phase of
the mission plus the latter part of launch
and the Mars Orbit Insertion (MOI).
mro_ab Merged SPK file covering the whole
aerobraking phase of the mission.
mro_pspN Merged SPK files covering earlier parts of
the PSP phase of the mission, covering as
follows:
pspN Begin date End date
---- ----------- -----------
psp1 2006 SEP 12 2007 JAN 01
psp2 2007 JAN 01 2007 APR 01
psp3 2007 APR 01 2007 JUL 01
psp4 2007 JUL 01 2007 OCT 01
psp5 2007 OCT 01 2008 JAN 01
psp6 2008 JAN 01 2008 APR 01
psp7 2008 APR 01 2008 JUL 01
psp8 2008 JUL 01 2008 OCT 01
psp9 2008 OCT 01 2009 JAN 01
MRO spacecraft structures SPK file:
mro_struct_v10 SPK file containing relative locations of MRO
solar array and HGA structures.
Additional SPK files with names that don't match any of the patterns
above may also be present in this directory. Usually, these files were
produced by the NAV or NAIF team for a specific purpose or customer.
If the name of the file of interest starts with ``spk_'', contact MRO
NAV with any questions about the file; otherwise, contact NAIF.
SPK File Naming Schema.
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The subsections below describe the SPK file naming schemes.
OD Solution SPK Files created by MRO NAV.
These files are automatically transferred from the MRO Project Data
Base (``ops'' DOM) within one hour after MRO NAV delivers them to the
DOM. The names of these files have the following form:
spk_psp_recIIIII_JJJJJ_MMMMM_K-vV
where
JJJJJ is the number of the first reconstructed
orbit covered by the file.
IIIII is the number of the last reconstructed orbit
covered by the file.
MMMMM is the number of the last predicted orbit
covered by the file.
K is the flag indicating what type of data
stored in the file. If K is set to ``r'', the
file contains only reconstructed data. If K
is set to ``p'', the file contains both
reconstructed and predicted data.
V is the file version.
Merged SPK File created by NAIF
These files are created are created manually (for Cruise at the end of
the Cruise phase of the mission) or automatically (for Aerobraking,
PSP, and Extended phases of the mission) from the MRO NAV regular OD
solution SPKs or manually from SPK files sets coming from other data
providers. The file names have the format:
mro_XXXX[_YYYYY][_PPPPPP][_VVV]
where
XXXX is full or abbreviated mission phase name
(examples: _cruise, _ab, _psp1, _psp2,
_ext1); due to the file size constraint the
PSP and extended phases will be broken into
sub-intervals, each covering 3-month time
span;
_YYYYY is an optional string referring to a
particular part of a mission phase;
_PPPPPP is an optional string identifying team, if
not MRO NAV, produced OD solution contained
in the file
_VVV is an optional string referring to OD
solution version number (examples: _v1, _v4);
Supplementary/Meta Information Files.
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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 phases of the mission (aerobraking,
PSP, etc.) Orbit number files have the same names as the corresponding
SPK file but with the extension ".bsp" replaced by ".orb" or ".norb".
The longest of the recent regularly updated orbit number files is kept
in the file with additional extension ".long" (for example, the
ever-growing predicted orbit number file for PSP is called
"mro_psp.norb" while its longest recent version is called
"mro_psp.norb.long").
The orbit number files with the ".orb" extension contain data that
follow the "periapsis-to-periapsis" orbit numbering scheme -- with the
orbit number changing at periapsis.
The orbit number files with the ".norb" extension contain data that
follow the "node-to-node" orbit numbering scheme -- with the orbit
number changing at the descending node.
The information contained in the orbit number files includes the orbit
number, periapsis or descending node UTC and SCLK time, apoapsis or
ascending UTC time and additional information for periapsis or
descending node such as subsolar and subspacecraft longitude/latitude.
Details Regarding Merged SPK File for Current Phase
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During orbital phases of the mission, the merged SPK file(s) for the
current phase of the mission is updated (appended) automatically every
time MRO 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.
Merged SPK files for all completed mission phases stay unmodified and
have detached labels of good quality.
Archived Files
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Original MRO NAV regular OD solution SPK files, original SPK files
created by other data producers and merged files created at NAIF are
archived on CD-ROM and not present in this directory. Refer to the
``archived.txt'' file in this directory for a complete list of these
files.
Though NAIF recommends to use merged SPKs located in this directory
which were made by merging data from the original products, someone
can obtain archived files by submitting an e-mail request to NAIF
using contact information given above.