The Mars 2020 SPICE Data Archive
========================================================================
Last update: March 20, 2023
Introduction
============
This document describes the Mars 2020 SPICE archive, containing
observation geometry and other ancillary data in the form of SPICE
System kernel files for the Mars 2020 rover and its instruments and
structures. It describes the archive directory structure, kernels
included in the archive, their naming conventions, and provides
pointers to the SPICE software and documentation.
Table of Contents
=================
Introduction
Table of Contents
Overview
Errata
Archive Contents
Kernel Types
Archived Kernel Details
SPK Files
PCK Files
IK Files
CK Files
LSK Files
SCLK Files
FK Files
MK Files
Miscellaneous Files
Checksum Files
File Formats
SPICE Software and Documentation
Contact Information
Cognizant Persons
Overview
========
This archive includes the complete set of the Mars 2020 Perseverance
Rover Mission data files (kernel files), which can be accessed using
SPICE software. The SPICE data contain geometric and other ancillary
information needed to recover the full value of science instrument
data. In particular SPICE kernels provide spacecraft and planetary
ephemerides, spacecraft and instrument orientation, instrument
mounting alignments, and data needed for relevant time conversions.
Data in the SPICE kernel files must be accessed using the software
called the SPICE Toolkit produced and distributed by the Navigation
and Ancillary Information Facility (NAIF) Node of the Planetary Data
System.
This archive includes data covering from Mars 2020 launch, 2020-07-30,
through the end time of the latest rover surface traverse position SPK
file supplied in the archive. Until the end of the spacecraft lifespan
this archive will be accumulating with new data added according to the
project archiving plan.
Back to Table of Contents
Errata
======
1. This document is a simple HTML document. Providing documents in a
simple mark-up format was allowed by earlier versions of the PDS4
Standards but became prohibited in later versions starting summer
2015. Since using HTML documents was compliant at the time when a
similar document was first provided in the MAVEN PDS4 archive and
since NAIF strives to make bundle description document format and
style consistent across all archives, this document continues
to exist in this archive as an HTML document.
2. The XML labels of the ancillary products have the reference_type
attribute of the Internal_Reference association within the
Reference_List class of the Context_Area class pointing to the latest
archive description document set to "ancillary_to_data" which is not
correct. The correct value "ancillary_to_document" could not be used
in these labels because it is not available in the PDS4 information
model (IM) 1.5.0.0 used by this archive. This value was added to IM
only in the version 1.14.0.0.
3. Only a partial structures IK with a few antenna FOVs is included.
IKs for other instruments may be added in a future release.
4. The Mars 2020 FK does not define frames for majority of instruments.
A more complete FK may be added in a future release.
5. RSM and RA orientation CKs have sparse coverage. CKs with more
complete coverage may be added in a future release.
6. No HGA CK is included. HGA CK for initial 90 Sols may be added in a
future release.
7. No Helicopter Technology Demonstration Ingenuity kernels are included.
SPK, CKs, IKs, and FK updates for the helicopter may be added in a
future release.
8. The following SPK and CK files
m2020_surf_hga_tlm_0179_0299_v1.bc
m2020_surf_ra_tlmenc_0000_0089_v1.bc
m2020_surf_ra_tlmenc_0089_0179_v1.bc
m2020_surf_ra_tlmenc_0179_0299_v1.bc
m2020_surf_ra_tlmres_0000_0089_v1.bc
m2020_surf_ra_tlmres_0089_0179_v1.bc
m2020_surf_ra_tlmres_0179_0299_v1.bc
m2020_surf_rover_tlm_0000_0089_v1.bc
m2020_surf_rover_tlm_0089_0179_v1.bc
m2020_surf_rover_tlm_0179_0299_v1.bc
m2020_surf_rsm_tlmenc_0000_0089_v1.bc
m2020_surf_rsm_tlmenc_0089_0179_v1.bc
m2020_surf_rsm_tlmenc_0179_0299_v1.bc
m2020_surf_rsm_tlmres_0000_0089_v1.bc
m2020_surf_rsm_tlmres_0089_0179_v1.bc
m2020_surf_rsm_tlmres_0179_0299_v1.bc
m2020_surf_rover_loc_0000_0089_v1.bsp
m2020_surf_rover_loc_0089_0179_v1.bsp
m2020_surf_rover_loc_0179_0299_v1.bsp
m2020_surf_rover_tlm_0000_0089_v1.bsp
m2020_surf_rover_tlm_0089_0179_v1.bsp
m2020_surf_rover_tlm_0179_0299_v1.bsp
were erroneously archived in BIG-IEEE binary format. They will
be superseded by later-version files in the correct LTL-IEEE binary
format in a future archive release.
Back to Table of Contents
Archive Contents
================
Files in this archive are organized into a set of subdirectories
below the top-level directory. The following diagram shows the
structure and content of these directories. The directory names are
enclosed in square brackets ([]).
[top-level-directory]
|
|- bundle_mars2020_spice_v*.xml Bundle PDS4 label, one or more versions.
|- readme.txt Bundle top-level readme file.
|
|-[spice_kernels] Directory containing SPICE kernels.
| |
| |- collection_spice_kernels_v*.xml PDS4 labels for Spice Kernels collections.
| |- collection_spice_kernels_inventory_v*.tab
| | Spice Kernels collections' inventories.
| |
| |-[ck] Directory containing CK files.
| | |
| | |-- *.bc Binary CK files.
| | +-- *.xml PDS4 labels for CK files.
| |
| |-[fk] Directory containing FK files.
| | |
| | |-- *.tf Text FK files.
| | +-- *.xml PDS4 labels for FK files.
| |
| |-[ik] Directory containing IK files.
| | |
| | |-- *.ti Text IK files.
| | +-- *.xml PDS4 labels for IK files.
| |
| |-[lsk] Directory containing LSK files.
| | |
| | |-- *.tls Text LSK files.
| | +-- *.xml PDS4 labels for LSK files.
| |
| |--[mk] Directory containing MK files.
| | |
| | |-- *.tm Text Meta-kernel files.
| | +-- *.xml PDS4 labels for MK files.
| |
| |-[pck] Directory containing PCK files.
| | |
| | |-- *.tpc Text PCK files.
| | +-- *.xml PDS4 labels for PCK files.
| |
| |-[sclk] Directory containing SCLK files.
| | |
| | |-- *.tsc Text SCLK files.
| | +-- *.xml PDS4 labels for SCLK files.
| |
| +-[spk] Directory containing SPK files.
| |
| |-- *.bsp Binary SPK files.
| +-- *.xml PDS4 labels for SPK files.
|
|-+-[miscellaneous] Directory miscellaneous files.
| |
| |- collection_miscellaneous_v*.xml PDS4 labels for miscellaneous collections.
| |- collection_miscellaneous_inventory_v*.tab
| | Miscellaneous collections' inventories.
| |
| +-[checksum] Directory containing checksum files.
| |
| |-- *.tab Text checksum files.
| +-- *.xml PDS4 labels for checksum files.
|
+-[document] Directory containing documents.
|
|- collection_document_v*.xml PDS4 labels for document collections.
|- collection_document_inventory_v*.tab
| Document collections' inventories.
|
|- spiceds_v*.html This file and its earlier versions.
+- spiceds_v*.xml PDS4 labels for this file and its earlier versions.
Back to Table of Contents
Kernel Types
============
Different SPICE kernel types are used to store different kinds of
ancillary data.
SPK (Spacecraft Planet Kernel) files contain ephemerides (position
and velocity) for spacecraft, planets, satellites, comets and
asteroids as well as for moving or fixed spacecraft and instrument
structures. SPK files are located under the spice_kernels/spk
directory of this archive.
PCK (Planetary Constants Kernel) files contain certain physical,
dynamical and cartographic constants for target bodies, such as size
and shape specifications, and orientation of the spin axis and prime
meridian. PCK files are located under the spice_kernels/pck
directory of this archive.
IK (Instrument Kernel) files contain instrument parameters relevant
for computing an instrument's geometry such as field-of-view
definitions, CCD and optical distortion characteristics, and internal
timing parameters. IK files are located under the spice_kernels/ik
directory of this archive.
CK (C-matrix Kernel) files contain time varying orientations for
spacecraft, spacecraft structures, and articulating science
instruments. CK files are located under the spice_kernels/ck
directory of this archive.
LSK (Leapseconds Kernel) files contain the leapseconds and the
values of other constants required to perform a transformation
between Universal Time Coordinated (UTC) and Ephemeris time (ET),
which is also known as Barycentric Dynamical Time (TDB). LSK
files are located under the spice_kernels/lsk directory of
this archive.
SCLK (Spacecraft Clock Kernel) files contain on-board clock
calibration data required to perform a transformation between
Ephemeris time (ET) and spacecraft on-board time (SCLK). SCLK files
are located under the spice_kernels/sclk directory of this
archive.
FK (Frame definitions Kernel) files contain information required to
define reference frames, sources of frame orientation data and
connections between these frames and other frames supported within
the SPICE system. The science instrument frame definitions provided
in the FK files include mounting alignment information for the
instruments. FK files are located under the spice_kernels/fk
directory of this archive.
MK (Meta-Kernel) files list sets of related SPICE kernels that
should be used together, providing an easy way to make data from
these kernel sets available to a SPICE-based application by loading
meta-kernels into the program using the high level SPICE data loader
routine FURNSH. MK files are located the spice_kernels/mk
directory of this archive.
Archived Kernel Details
=======================
The subsections below provide details, such as file naming
conventions and specific details, for each of the kernel types
included in this archive.
Back to Table of Contents
SPK Files
SPK (Spacecraft Planet Kernel) files contain ephemerides (position
and velocity) for spacecraft, planets, satellites, comets and
asteroids as well as for moving or fixed spacecraft and instrument
structures.
This archive includes binary SPK files containing the following
kinds of ephemeris data:
- planetary ephemeris SPKs
These SPKs contain ephemeris data for the Solar System
planet barycenters, and Sun, Mercury, Venus, Earth, and
Moon, determined by the JPL Solar System Dynamics group and
are named DEXXX, e.g. DE430.
- Martian satellite ephemeris SPKs
These SPKs contain ephemeris data for Mars, Phobos, Deimos,
Sun, Earth barycenter, and Earth, determined by the
JPL Solar System Dynamics group and are named MARXXX, e.g.
MAR097.
- reconstructed spacecraft cruise trajectory SPKs
These SPKs contain the reconstructed Mars 2020 spacecraft
trajectory for cruise determined by the Mars 2020 Navigation
(NAV) team, JPL.
- reconstructed spacecraft EDL trajectory SPKs
These SPKs contain the reconstructed Mars 2020 spacecraft
trajectory during Entry Descent Landing (EDL) determined by
the Mars 2020 EDL Team, JPL.
- actual landing site position SPKs
These SPKs contain the actual location of the Mars 2020
landing site in the Mars body-fixed frame (IAU_MARS,
based on IAU 2000 Mars rotation constants), determined by
the Mars 2020 EDL Team, JPL.
- rover at landing site position SPKs
These SPKs contain the position of the Mars 2020 rover
fixed at the landing site. These files were used during
operations by CHRONOS and other applications that were not
sensitive to the local rover movements.
- structures SPKs
These SPKs contain fixed locations of of selected rover
structures and instruments such as Remote Sensing Mast (RSM),
Robotic Arm (RA), and cameras. The data included in the file
are based of dimensions from the spacecraft engineering drawings.
- localized rover path and site locations SPKs
These SPKs contain the locations of the sites along the path
relative to the center of Mars and the location of the rover
relative to the center of Mars, created by the NAIF, JPL.
These SPKs were created using localized data available in the
PLACES server developed and maintained by the Mars 2020 Operations
Product Generation Subsystem (OPGS) Team. The set of localized
data in the PLACES server included rover and site location data
for a limited set of localization points determined by tracing
the rover traverse on high resolution maps, combined a subset
of telemetry products to create a more complete set of location
points. Because the telemetry products used in this process
included only image headers and mobility summaries, containing
rover location during non-motion periods, and did not include
data from the high-rate mobility history products containing
rover location during motion periods, these SPKs do not provide
real data during motion but instead provide interpolated
values.
In global context the data provided in these SPKs is
significantly more accurate than telemetered rover position
estimated on-board. Because of this these SPKs should be
preferred to the telemetry-based rover path SPKs.
- telemetry-tased rover path and site locations SPKs
These SPKs contain the locations of the sites along the path
relative to the landing site and location of the rover relative
to these sites.
These SPKs were created using telemetry data available in the
PLACES server developed and maintained by the Mars 2020 Operations
Product Generation Subsystem (OPGS) Team. The set of telemetry
data in the PLACES server included rover and site location data
from only a subset of telemetry products containing such
information. Specifically, it included data from the product
and image headers and mobility summaries, containing rover
location during non-motion periods, and did not include data
from the high-rate mobility history products containing rover
location during motion periods. For this reason, these SPKs do
not provide real data during motion but instead provide
interpolated values.
Because data provided in these SPKs is based on telemetered
rover position estimated on-board, these SPKs are only as
accurate as that estimate, which, depending on the traverse
distances, slippage and sliding, can off by meters.
The SPK files are provided under the spice_kernels/spk
directory and are named according to the following schemes:
- planetary ephemeris SPKs
deVVVs.bsp
where
VVV is the ephemeris version.
s (optional) indicates that the original file
coverage was shortened to reduce the file
size.
- Martian satellite ephemeris SPKs
marVVVs.bsp
where
VVV is the ephemeris version.
s (optional) indicates that the original file
coverage was shortened to reduce the file
size.
- reconstructed spacecraft cruise trajectory SPKs
m2020_cruise_odSSS_vV.bsp
where
SSS is the orbit determination solution number.
V is the version; the file with the latest
version supersedes all similarly named files
with earlier versions.
- reconstructed spacecraft EDL trajectory SPKs
m2020_edl_vVV.bsp
where
VV is the version; the file with the latest
version supersedes all similarly named files
with earlier versions.
- actual landing site position SPKs
m2020_ls_opsYYMMDD_iauYYYY_vV.bsp
where
YYMMDD is the date when the landing site location
stored in the file was determined or
released.
YYYY is the publication year of the IAU Mars
rotation model, with which this SPK should be
used.
V is the version; the file with the latest
version supersedes all similarly named files
with earlier versions.
- rover at landing site position SPKs
m2020_atls_opsYYMMDD_vV.bsp
where
YYMMDD is the date consistent with the corresponding
landing site position SPK.
V is the version; the file with the latest
version supersedes all similarly named files
with earlier versions.
- structures SPKs
m2020_struct_vVV.bsp
where
VV is the version; the file with the latest
version supersedes all similarly named files
with earlier versions.
- localized rover path and site locations SPKs
m2020_surf_rover_loc_SSSS_ssss_vV.bsp
where
SSSS is the file coverage start SOL.
ssss is the file coverage end SOL.
V is the version; the file with the latest
version supersedes all similarly named files
with earlier versions.
- telemetry-tased rover path and site locations SPKs
m2020_surf_rover_tlm_SSSS_ssss_vV.bsp
where
SSSS is the file coverage start SOL.
ssss is the file coverage end SOL.
V is the version; the file with the latest
version supersedes all similarly named files
with earlier versions.
The most detailed description of the data in each SPK file is
provided in metadata included inside the comment area of the file.
This information can be viewed using the utility program COMMNT
included in the NAIF Toolkit.
Back to Table of Contents
PCK Files
PCK (Planetary Constants Kernel) files contain certain physical,
dynamical, and cartographic constants for target bodies, such as
size and shape specifications, and orientation of the spin axis and
prime meridian.
This archive includes generic text PCK files produced by NAIF,
containing data from the reports of the IAU Working Group on
Cartographic Coordinates and Rotational Elements. The generic text
PCK version 00010 contains data from the 2009 report.
The PCK files are provided under the spice_kernels/pck
directory and are named according to the following scheme:
- generic text PCKs
pckVVVVV.tpc
where
VVVVV is the version; the file with the largest
number is the latest, but the user of PCK
data must decide if the latest version,
or an earlier version, is appropriate
for his/her analysis task.
The most detailed description of the data in a text PCK file is
provided in metadata included inside the description area of the
file. This information can be viewed using any text editor program.
Back to Table of Contents
IK Files
IK (Instrument Kernel) files contain instrument parameters relevant
for computing an instrument's observation geometry such
field-of-view definitions, CCD and optical distortion
characteristics, and internal timing parameters.
This archive includes text IK files for Mars 2020 instruments, for
which common instrument geometric parameters normally stored in IKs
are applicable, such as the rover cameras, a few other rover-mounted
instruments and rover mounted antennas.
The IK files are provided under the spice_kernels/ik
directory and are named according to the following scheme:
- instruments and antennae IK files
m2020_NAME_vVV.ti
where
NAME is the instrument acronym:
struct (for miscellaneous structures,
e.g. antennae)
VV is the version; the file with the latest
version supersedes all similarly named
files with earlier versions.
The most detailed description of the data in a text IK file is
provided in metadata included inside the description area of the
file. This information can be viewed using any text editor program.
Back to Table of Contents
CK Files
CK (C-matrix Kernel) files contain time varying orientations for
spacecraft, articulating spacecraft structures, and articulating
science instruments.
This archive includes binary CK files containing the following kinds
of orientation data:
- reconstructed spacecraft cruise orientation CKs
These CKs contain the reconstructed Mars 2020 spacecraft
cruise attitude determined on-board and downlinked in
spacecraft telemetry, determined by the Mars 2020 Attitude
Control System (ACS) Team, JPL.
The set of CKs provided by the Mars 2020 ACS Team includes a CK
with complete cruise orientation based on H-vector direction
without modeling spin, a CK with fully reconstructed orientation
based on real-time quaternions covering only communication periods,
a CK with high-rate high-accuracy orientation covering only a few
very short periods during certain events sugh as: attitude
maneuvers, ACS calibration activities, or thruster firing events.
- reconstructed spacecraft EDL orientation CKs
These CKs contain the reconstructed Mars 2020 spacecraft EDL
attitude, from the EDL entry point to landing, determined
by Mars 2020 EDL team, JPL.
- reconstructed rover surface orientation CKs
These CKs contain the orientation of the rover relative to the
local level frame, created by NAIF, JPL.
These CKs were created using telemetry data available in the
PLACES server developed and maintained by the Mars 2020 OPGS Team.
The set of telemetry data in the PLACES server included rover
orientation data only from a subset of telemetry products
containing such information. Specifically, it included data
from the product and image headers and mobility summaries,
containing rover orientation during non-motion periods, and did
not include data from the high-rate mobility history products,
containing rover orientation during motion periods. For this
reason, these CKs do not provide real data during motion but
instead provide interpolated values.
Due to incomplete source data these CKs have gaps in coverage,
which can be closed, if needed, using the CKSPANIT utility
program.
- reconstructed articulating structures orientation CKs
These CKs contain the orientation of the Remote Sensing Mast
(RSM), Robotic Arm (RA), and High Gain Antenna (HGA) relative
to the rover frame, created by NAIF, JPL.
These CKs were created using telemetry data available in the
PLACES server developed and maintained by the Mars 2020 OPGS Team.
The set of telemetry data in the PLACES server included
structure articulation angle data from only a subset of
telemetry products containing such information. Specifically,
it included data from the product and image headers and
articulation summaries, containing structure articulation
angles during non-articulation periods, and did not include
data from the high-rate articulation history products,
containing structure articulation angles during articulation
periods. For this reason, these CKs do not provide real data
during articulation but instead provide interpolated values.
The sets of CKs for RSM and RA include CKs based on encoder
angles (less accurate but more complete) and CKs based on
resolver angles (more accurate but less complete).
While RSM and HGA CKs based on resolver angles provide accurate
orientation matching that computed in the flight software, the
RA CKs do not because the simple forward kinematics approach
implemented using these CKs and corresponding frame chains does
not model flexing of the RA which can lead to end point
orientation errors of a degree or more for some RA
configurations.
Due to incomplete source data these CKs have gaps in coverage,
which can be closed, if needed, using the CKSPANIT utility
program.
The CK files are provided under the spice_kernels/ck
directory and are named according to the following scheme:
- reconstructed spacecraft cruise orientation CKs
m2020_cruise_recon_TYPE_vV.bc
where
TYPE specifies the basis of the orientation
nospin (for H-vector direction without spin)
rawrt (for real-time quaternions during comms)
raweng (for high-rate quaternions during events)
VV is the version; the file with the latest
version supersedes all similarly named files
with earlier versions.
- reconstructed spacecraft EDL orientation CKs
m2020_edl_rec_vVV.bc
where
V is the version; the file with the latest
version supersedes all similarly named files
with earlier versions.
- reconstructed rover surface orientation CKs
m2020_surf_rover_tlm_SSSS_ssss_vV.bc
where
SSSS is the file coverage start SOL.
ssss is the file coverage end SOL.
V is the version; the file with the latest
version supersedes all similarly named files
with earlier versions.
- reconstructed articulating structures orientation CKs
m2020_surf_STRUC_TYPE_SSSS_ssss_vV.bc
where
STRUC is the articulating structure
hga (for High Gain Antenna)
ra (for Robotic Arm)
rsm (for Remote Sensing Mast)
TYPE specifies the basis of the orientation
tlmenc (for encoder-based orientation)
tlmres (for resolver-based orientation)
SSSS is the file coverage start SOL.
ssss is the file coverage end SOL.
V is the version; the file with the latest
version supersedes all similarly named files
with earlier versions.
The most detailed description of the data in each CK file is
provided in metadata included inside the comment area of the file.
This information can be viewed using the utility program COMMNT
included in the NAIF Toolkit.
Back to Table of Contents
LSK Files
LSK (Leapseconds Kernel) files contain the leapseconds and the
values of other constants required to perform a transformation
between Universal Time Coordinated (UTC) and Ephemeris time (ET),
also known as Barycentric Dynamical Time (TDB).
This archive includes generic text LSK files produced by NAIF,
containing leapsecond information based on the IERS announcements.
The generic text LSK version 0012 contains leap second data up to
and including the January 1, 2017 leapsecond.
The LSK files are provided under the spice_kernels/lsk
directory and are named according to the following scheme:
- generic text LSKs
naifVVVV.tls
where
VVVV is the version; the file with the latest
version supersedes all similarly named
files with earlier versions.
The most detailed description of the data in a text LSK file is
provided in metadata included inside the description area of the
file. This information can be viewed using any text editor program.
Back to Table of Contents
SCLK Files
SCLK (Spacecraft Clock Kernel) files contain on-board clock
calibration data required to perform a mapping between Ephemeris
time (ET) and spacecraft on-board time (SCLK).
This archive includes text SCLK files containing the following kinds of
data:
- official Mars 2020 on-board clock correlation SCLKs
These SCLKs contain a tabulation of data needed for converting
time measurements between ephemeris time (ET) and Mars 2020
spacecraft clock time (SCLK). They are made from similar
files -- SCLK/SCET file, or SCLKvSCET file -- produced by
mission Time Correlation Subsystem (TCS) team.
The official on-board correlation SCLK files used in operations
and included in this data set provide correlation that is
incorrect in an absolute sense by as much as 3 seconds during
surface operations. The main reason for this error is the loose
time correlation requirement for surface operations intended
to keep backward compatibility between correlation versions
and minimize the impact of deployment of the new correlation
across the ground data system.
- improved Mars 2020 on-board clock correlation SCLKs
These improved SCLK files contain on-board clock correlation
accurate to a few tens of milliseconds or better, made
specifically for archiving to fix large correlation errors
present in the official SCLKs.
- Local Mean Solar Time (LMST) SCLKs
These SCLK files provide a way of converting between the Local
Mean Solar Time (LMST) time system used during surface
operations and other time systems. LMST was introduced as a
replacement of the Local True Solar Time (LTST) because a time
system with a constant duration of a second was needed for use
in the planning and sequencing processes. The LMST is
essentially a linear approximation of the local true solar time
with the rate set equal to the mean Mars local second duration
and the initial reference point set to LMST midnight of the
landing SOL. Due to ellipticity of the Mars orbit this
approximation is periodic and deviates from the LTST by as much
as 50 minutes during Martian year.
The SCLK files are provided under the spice_kernels/sclk
directory and are named according to the following scheme:
- official Mars 2020 on-board clock correlation SCLKs
m2020_168_sclkscet_VVVVV.tsc
where
VVVVV is the version; the file with the latest
version supersedes all similarly named
files with earlier versions.
- improved Mars 2020 on-board clock correlation SCLKs
m2020_168_sclkscet_refit_vVV.tsc
where
VV is the version; the file with the latest
version supersedes all similarly named
files with earlier versions.
- Local Mean Solar Time (LMST) SCLKs
m2020_lmst_opsYYMMDD_vV.tsc
where
YYMMDD is the date consistent with the corresponding
landing site position SPK.
V is the version; the file with the latest
version supersedes all similarly named
files with earlier versions.
The most detailed description of the data in a text SCLK file is
provided in metadata included inside the description area of the
file. This information can be viewed using any text editor program.
Back to Table of Contents
FK Files
FK (Frame definitions Kernel) files contain information required to
define reference frames, sources of frame orientation data and
connections between these frames and other frames supported within
the SPICE system. The science instrument frame definitions provided
in the FK files include mounting alignment information for the
instruments.
This archive includes text FK files defining reference frames for
the Mars 2020 rover, its structures, and science instruments.
These FKs were produced by NAIF using the spacecraft and instrument
design documentation as well as actual instrument alignment values
determined pre-launch and as the result of in-flight calibrations.
The FK files are provided under the spice_kernels/fk
directory and are named according to the following scheme:
- Mars 2020 mission FK files
m2020_vVV.tf
where
VV is the version; the file with the latest
version supersedes all similarly named
files with earlier versions.
The most detailed description of the data in a text FK file is
provided in metadata included inside the description area of the
file. This information can be viewed using any text editor program.
Back to Table of Contents
MK Files
Meta-kernel (MK) files (a.k.a 'furnsh' files) provide lists of the
archived kernels included in this archive suitable for loading into
a SPICE-based application via the high level SPICE data loader
routine FURNSH. Using meta-kernels makes it easy to load with
one call a comprehensive SPICE data collection for a given period.
This archive includes the following kinds of MK files:
- whole mission MK files
These MKs with provide the complete sets of best available
kernels.
- CHRONOS MK files
These MKs provide only kernels needed for the SPICE CHRONOS
time-conversion program and include the CHRONOS configuration
parameters (spacecraft ID, planet ID, landing UTC, landing SOL
index, and Sun GM).
These MKs provide the same sets of kernels as they provided during
OPS except for the cruise and EDL SPKs.
The text MK files are provided under the spice_kernels/mk
directory and are named according to the following scheme:
- whole mission MK files
m2020_vVV.tm
when
VV is the version; the file with the latest
version supersedes all similarly named
files with earlier versions.
- CHRONOS MK files
m2020_chronos_vVV.tm
when
VV is the version; the file with the latest
version supersedes all similarly named
files with earlier versions.
Although the meta-kernels were created such that on a UNIX
workstation they can be loaded into a SPICE-based application
directly from the directory in which they reside -- because the
PATH_VALUES keyword is set to '..' and '/' is used as the path
delimiter -- it is recommended that users make local copies of these
files and update the PATH_VALUES keyword in each of them to point to
the actual location of the archive's 'spice_kernels' directory on
their system. Additional changes including replacing '/' and '\' in
all path specifications and converting UNIX line terminators to
terminators native to the user's system may be required to use these
meta-kernels on non-UNIX workstation.
The following guidelines were followed to pick and set priority --
determined by the order in which the kernel files are listed, with
the latest one taking precedence -- for the kernel files included in
these meta-kernels:
- the latest archived versions of LSK, PCK, on-board clock and
LMST SCLKs, IKs, FK, planetary ephemeris SPK, satellite
ephemeris SPK, cruise SPK, EDL SPK and CK, landing site SPK,
localized rover surface path SPK, and rover, RSM, RA, and HGA
CKs were included
- only the reconstructed cruise CK based on real-time telemetry
during communication periods was included.
Additional description of the kernels sets listed in a text MK file is
provided in metadata included inside the description area of the
file. This information can be viewed using any text editor program.
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Miscellaneous Files
===================
Miscellaneous files provide value added elements that are outside the
scope of the PDS archive requirements. Miscellaneous files included in
this archive are currently limited to checksum files.
The subsection below provides details for these files.
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Checksum Files
A checksum file provides a table of MD5 checksums for all files in the
archive as of a particular archive (bundle) version, including
checksums for all previous checksums files and their labels but
excluding the checksum for the checksum file itself and its label.
The checksum files are provided under the miscellaneous/checksum
directory and are named according to the following scheme:
- Mars 2020 checksum files
checksum_vVVV.tab
where
VVV is the version; the file with the latest
version supersedes all similarly named
files with earlier versions and can be
used to validate the archive in its
entirety.
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File Formats
============
All text documents, checksum files, and other meta information files
such as descriptions, detached PDS4 labels, and inventory tables, are
stream format files, with a carriage return (ASCII 13) and a line feed
character (ASCII 10) at the end of the records. This allows the files
to be read by most operating systems.
The text kernel files in this archive -- LSKs, PCKs, SCLKs, IKs, FKs,
and MKs -- are UNIX text files, with a line feed character (ASCII 10)
at the end of the line, and binary kernel files -- SPKs and CKs -- are
IEEE LSB binary files. While data files in this archive can be used
'as is' with SPICE toolkits for the majority of supported environments,
converting the files to the binary or text format native to the user's
computer may be required for use of the data with FORTRAN toolkits on
incompatible environments. Refer to the documentation provided with the
SPICE Toolkit to find out whether conversion is needed in each specific
case.
NAIF provides a tool (BINGO) that can convert either binary or text
kernels from one format to another. This means that text files can
have their line terminator changed and binary files can be converted
to the native format of the platform of interest. BINGO is available
from the utilities page at the NAIF Node of the PDS:
https://naif.jpl.nasa.gov/naif/utilities.html
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SPICE Software and Documentation
================================
The latest SPICE Toolkit for a variety of computer platforms,
additional utility programs, documentation, tutorials, and hands-on
lessons are available at the NAIF Node of the PDS:
https://naif.jpl.nasa.gov
specifically:
Toolkit: https://naif.jpl.nasa.gov/naif/toolkit.html
Utilities: https://naif.jpl.nasa.gov/naif/utilities.html
Tutorials: https://naif.jpl.nasa.gov/naif/tutorials.html
Lessons: https://naif.jpl.nasa.gov/naif/lessons.html
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Contact Information
===============================
PDS Navigation and Ancillary Information Facility (NAIF),
MAIL STOP 301-121
Jet Propulsion Laboratory
California Institute of Technology
4800 Oak Grove Drive
Pasadena, CA, 91109-8099
818-354-8136
WWW Site: https://naif.jpl.nasa.gov
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Cognizant Persons
=================
This archive was produced by Marc Costa Sitja, Boris Semenov,
Matthew Barnes, and Alyssa Bailey, Planetary Data System Navigation
and Ancillary Information Facility Node, Jet Propulsion Laboratory,
Pasadena, California.
End of Mars 2020 SPICE archive description.
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