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<div><br></div>
<div>This message contains several announcements and questions.</div>
<div><br></div>
<div><br></div>
<div>Merged SPICE Tutorials</div>
<div>--------------------------------------------------------------</div
>
<div>A few of you have asked for an integrated package of the SPICE
tutorials. We took this to mean a single PDF file. That is now
available under the Tutorials web page (see the bottom entry,
SPICE_Tutorials_Merged") at the NAIF website: <font
color="#000000"> http://naif.jpl.nasa.gov/naif/tutorials.html</font>.
This is an 800+ page PDF file.</div>
<div><br></div>
<div><br></div>
<div><br></div>
<div>FURNSH Kernels for Archived SPICE Data Sets</div>
<div>--------------------------------------------------------------</div
>
<div>A few months ago NAIF began providing so-called FURNSH kernels
for the PDS archived SPICE data sets. A FURNSH kernel, sometimes
called a meta-kernel, provides a convenient listing of all* the SPICE
kernels that should be used together for a stated mission period. For
some missions the breakdown is by calender year, while for others
there is a single FURNSH kernel covering the entire mission.</div>
<div><br></div>
<div>Your application program need "load" only the FURNSH
kernel(s) for the period(s) of interest and this will automatically
load all of the individual SPKs, CKs, etc. that apply to that period.
(This assumes you have downloaded the entire SPICE data set and have
modified the value assigned to the PATH_VALUES keyword to point to the
actual location of the SPICE data set's /data directory on your
computer!)</div>
<div><br></div>
<div>These FURNSH kernels are placed in the /extras/mk folder within
each archived data set. For instance, for the SPICE data that have
been formally archived for the Cassini-Huygens mission, the collection
of FURNSH kernels is found here: <font color="#000000">
ftp://naif.jpl.nasa.gov/pub/naif/pds/data/co-s_j_e_v-spice-6-v1.0/cos<span
></span>p_1000/extras/mk/</font></div>
<div><font face="Lucida Grande" size="-4"
color="#000000"><br></font></div>
<div>Should circumstances require a given FURNSH kernel be updated, a
new version is created. An improved trajectory file is an example of
such an update.</div>
<div><br></div>
<div>If you are unfamiliar with the notion of a FURNSH kernel, please
download and read pages 13-15 of the "Introduction to Kernels"
tutorial. This is a capability with which all SPICE users should be
familiar.</div>
<div><br></div>
<div><br></div>
<div>*NOTE: Cassini-Huygens is a special case. Only for this mission
(so far) was NAIF unable to select a complete set of kernels for a
given period of time. For Cassini it is not clear to NAIF which PCK a
particular customer would want to use, given that Cassini updated the
PCK with every new spacecraft trajectory solution.</div>
<div><br></div>
<div><br></div>
<div><br></div>
<div>Improved Information about PDS Archived SPICE Data Sets</div>
<div>--------------------------------------------------------------</div
>
<div>Until now anyone wishing to access the formally archived SPICE
data for a given mission had to either know where to find it on the
NAIF server using the FTP protocol, or, get to it through a Planetary
Data System central catalog interface that turns out not to be very
convenient for acquiring a complete archived SPICE data set.</div>
<div><br></div>
<div>A new web page has been added that improves the connection to all
archived SPICE data sets, including providing information about the
dates covered and the size of the data set in Mbytes.</div>
<div><br></div>
<div>This change is part of a broader set of changes to the NAIF
"Data" web pages aimed at better explaining what data are
available.</div>
<div><br></div>
<div>If you have occasion to try these web pages, we're interested in
your feedback on what works and what doesn't--how might we further
improve your access to SPICE kernels?</div>
<div><br></div>
<div><br></div>
<div><br></div>
<div>Interoperability of Ancillary Data on an International
Scale?</div>
<div>--------------------------------------------------------------</div
>
<div>This week it is possible that the international group known as
Committee on Space Research (COSPAR) will have endorsed the activities
of the fledgling International Planetary Data Alliance (IPDA)<font
color="#000000"> http://www.planetarydata.org/</font>, which is aimed
at establishing interoperability among planetary science data archive
systems. The primary focus of the IPDA will understandably be on
science instrument data... images, spectra, particle counts, etc.
But should the IPDA be encouraged at some future date to take up the
question of standards and mechanisms for achieving interoperability
across whatever ancillary data systems are used by the various
participating nations/agencies? Should you have any thoughts on this
topic you are encouraged to contact the current IPDA chairperson,
Maria Teresa Capria, or any of the IPDA members. Contact information
for these people may be found at: <font color="#000000">
http://www.planetarydata.org/Members</font>. Consider sending a copy
of your thoughts to the NAIF manager
(charles.acton@jpl.nasa.gov).</div>
<div><br></div>
<div><br></div>
<div><br></div>
<div>A Public SPICE Tools Repository?</div>
<div>--------------------------------------------------------------</div
>
<div>If you are reading this text you are probably rather familiar
with the kinds of tools (application and utility programs) the NAIF
Group provides in the SPICE Toolkits, and the few extra tools
available only from the utilities link on the NAIF webpage. This
rather tightly controlled situation is not likely to change, other
than NAIF will slowly add hopefully useful new tools as time
permits.</div>
<div><br></div>
<div>Perhaps some of you SPICE users have developed, or might develop,
tools you'd be willing to share with other SPICE users, either as
supported code or in an "you're-on-your-own" basis. Anyone
have any thoughts on this topic?</div>
<div><br></div>
<div> Might it be useful?</div>
<div> Portability issues?</div>
<div> Accuracy/correctness issues?</div>
<div> How maintain compatibility with SPICE Toolkits?</div>
<div> ITAR issues?</div>
<div> Liability concerns?</div>
<div> Intellectual property rights issues?</div>
<div> Where hosted? (Is there an existing site that would
work?)</div>
<div> How would it work?</div>
<div> Might such a repository also include APIs
(subroutines)?</div>
<div><br></div>
<div>If you have comments/ideas either send them to the NAIF manager
(charles.acton@jpl.nasa.gov) or, for broader viewing and feedback, to
the spice_discussion Mailman list
(spice_discussion@naif.jpl.nasa.gov).</div>
<div><br></div>
<div><br></div>
<div>Finally, don't forget....</div>
<div>--------------------------------------------------------------</div
>
<div>See the NAIF home page (<font
color="#000000">http://naif.jpl.nasa.gov/naif/pds.html</font>) for
announcements about the new leapseconds kernels (LSK) and the upcoming
SPICE training class.</div>
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