boogabooga
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So, two years ago I used the JPL HORIZONS system (http://ssd.jpl.nasa.gov/?horizons) to download the ephemeris file to add Sedna for use in this program. The conversation can be found here: http://www.orbiter-forum.com/showthread.php?t=31990
At that time, I added my e-mail address to their contact list. Today I got the following e-mail which I wanted to document here in case it might be useful to users of this program in the future.
I'm not sure if it means that the new SPK files will not be compatible with this program?
At that time, I added my e-mail address to their contact list. Today I got the following e-mail which I wanted to document here in case it might be useful to users of this program in the future.
Code:
Jon D. Giorgini Aug 22 at 11:39 PM
To
[[COLOR="Red"]Redacted by boogabooga[/COLOR]]
Who can stop reading:
---------------------
This email can be skipped if you do not use asteroid and comet small-body
SPK files generated by the JPL Horizons server, or know that software which
uses such SPK files has been built using version N0065 or later of the SPICE
Toolkit library.
Purpose:
--------
Asteroid and comet SPK trajectory files produced by the JPL Horizons
system will be changed from the current Type 1 format to a new Type 21
format.
The new format offers higher-fidelity reproduction of the trajectory
in some situations, primarily for close planetary encounters and over
long time-spans.
Use of the new trajectory files requires that application software be
re-linked to incorporate a new library reader but with no other changes
to user software.
SPK files for other classes of bodies are not affected, only asteroids
and comets from Horizons.
Contacts:
---------
(1) This notice is being sent to email addresses supplied to Horizons
by users over the last three years when generating small-body SPK files.
(2) Notice is being sent to internal JPL groups likely to have relevant
software and users.
(3) The NAIF Group recently sent a notice to subscribers of their SPICE
Announce mailing list.
(4) Some known developers have been contacted over the last year regarding
the change, since notice-of-intent was first posted in the Horizons system
news July 23, 2014 and then again on March 2 of 2015:
http://ssd.jpl.nasa.gov/?horizons_news
So you might receive more notice of this issue than you need, depending
on the extent your email address overlaps these lists.
Details
-------
A reader for the new file format was first included in the N0065 SPICE
Toolkit released by the NAIF Group in July 2014.
To use comet and asteroid SPK files generated by Horizons after the
format becomes active, software which reads small-body SPK files needs
to be re-linked against SPICE library version N0065 or greater.
No other change to user software beyond re-linking with the latest
SPICE Toolkit library to produce new executables is required.
The NAIF Group's Toolkit software is available here:
http://naif.jpl.nasa.gov/naif/toolkit.html
If user software is re-linked with the above N0065+ library, it will
automatically have access to the new reader and automatically use the
new file structure when the change becomes active, without additional
effort by users.
If not re-linked, user software will fail when trying to read the new
small-body SPK file format. Old/current Type 1 SPK files will NOT be
affected and so existing files will continue to be transparently readable.
Example files in both the current/old format and forthcoming new format
can be retrieved for testing from the anonymous FTP site:
ftp://ssd.jpl.nasa.gov/pub/xfr/example_type-01_OLD_smb.bsp
ftp://ssd.jpl.nasa.gov/pub/xfr/example_type-21_NEW_smb.bsp
The switch-date is not fixed; this email is primarily to inform and
accept potential feedback from key users. If a change after September
could present a problem, let me know.
-------------------------------------------------------------------------------
Jon Giorgini | Navigation & Mission Design Section
Senior Analyst | Solar System Dynamics Group
[email protected] | Jet Propulsion Laboratory
-------------------------------------------------------------------------------
I'm not sure if it means that the new SPK files will not be compatible with this program?