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--></style><title>New Leapsecond takes effect January 1,
2006</title></head><body>
<div><br></div>
<div> >>>>>>> IMPORTANT ANNOUNCEMENT
REGARDING A NEW LEAPSECOND <<<<<<<<<</div>
<div><br></div>
<div>This is a repeat of NAIF's August 12, 2005 announcement about the
new leapsecond</div>
<div>that will take effect on January 1... just a few days away. If
you are a user of</div>
<div>"SPICE" data please pay attention to this announcement!
If you have colleagues</div>
<div>who use SPICE data, please consider forwarding this message to
them.</div>
<div><br></div>
<div>Thanks from the NAIF Team.</div>
<div><br></div>
<div><br></div>
<div><br></div>
<div>On 2005 August 5, NAIF released the updated leapseconds
kernel</div>
<div><br></div>
<div> naif0008.tls<br>
</div>
<div>You may download the file using anonymous ftp from the NAIF
server:</div>
<div><br>
naif.jpl.nasa.gov<br>
<br>
in the path<br>
<br>
pub/naif/generic_kernels/lsk</div>
<div><br></div>
<div>Or use the URL:</div>
<div><br></div>
<div>
ftp://naif.jpl.nasa.gov/pub/naif/generic_kernels/lsk</div>
<div><br></div>
<div>The new kernel is a text file with Unix line termination. It is
suitable for</div>
<div>unix, PC/Linux and Mac/OSX machines.</div>
<div><br></div>
<div>A version suitable for PC/Windows or NT machines is also in the
same location;</div>
<div>it is named naif0008.tls.pc.</div>
<div><br></div>
<div>You may alternatively use your browser to get one of these
files:</div>
<div><br></div>
<div> http://naif.jpl.nasa.gov/naif/data.html</div>
<div><br></div>
<div>and then select "generic kernels" and then
"lsk".</div>
<div><br>
<br>
</div>
<div>This update includes the addition of a leapsecond at the end of
2005, announced</div>
<div>in IERS bulletin C, dated July 4, 2005. The URL for this
bulletin is:</div>
<div><br>
http://hpiers.obspm.fr/eoppc/bul/bulc/bulletinc.dat<br>
<br>
On 2006 January 1 00:00:00 UTC, the time offset between UTC and<br>
international atomic time (TAI) will be<br>
<br>
33 seconds<br>
<br>
At that time, the offset between UTC and barycentric dynamical
time<br>
("TDB," "ephemeris time," "ET") will be
approximately<br>
<br>
65.183926 seconds<br>
<br>
The new kernel affects SPICE ET/UTC and spacecraft clock
(SCLK)/UTC<br>
conversions for dates on or after<br>
<br>
January 1, 2006 UTC<br>
<br>
Results of time conversions performed with this kernel for earlier
dates will</div>
<div>match those obtained using the previous leapseconds kernel
(naif0007.tls).<br>
</div>
<div><br></div>
<div>If not already accomplished, SPICE users are strongly encouraged
to make this</div>
<div>update<b> *NOW*</b> before it takes effect in a few days..</div>
<div><br></div>
<div>It is *not* necessary to have a current version of the SPICE
Toolkit</div>
<div>in order to read this file: it is readable by all older
SPICE Toolkits as well.</div>
<div><br></div>
<div><br></div>
<div><br></div>
<div>Using an Inappropriate Text Kernel</div>
<div>----------------------------------</div>
<div><br></div>
<div>If you inadvertently use an LSK made for an operating system
using a text line</div>
<div>termination standard different from the OS you're using (e.g. you
use</div>
<div>naif0008.tls instead of naif0008.tls.pc, or vice-versa) you will
likely see a</div>
<div>SPICE error message that looks like this:</div>
<div><br></div>
<div
>====================================================================<span
></span>============<br>
<br>
Toolkit version: N0058<br>
<br>
SPICE(INCOMPATIBLEEOL) --<br>
<br>
Text file 'naif0008.tls.pc' contains lines terminated with 'CR-LF'
while the<br>
expected terminator for this platform is 'LF'. This text file cannot
be<br>
processed.<br>
<br>
A traceback follows. The name of the highest level module is
first.</div>
<div>FURNSH --> ZZLDKER --> ZZASCII<br>
</div>
<div
>====================================================================<span
></span>============</div>
<div><br></div>
<div><br></div>
<div>or, if using an Toolkit older than N0057, an error message like
this:</div>
<div><br></div>
<div
>====================================================================<span
></span>============<br>
<br>
Toolkit version: N0058<br>
<br>
SPICE(MISSINGTIMEINFO)<br>
<br>
The following, needed to convert between the uniform time scales,
could not be<br>
found in the kernel pool: DELTET/DELTA_T_A, DELTET/K, DELTET/EB,
DELTET/M.<br>
<br>
A traceback follows. The name of the highest level module is
first.<br>
SPACIT --> SPASUM --> SUMSPK --> SPKWSS --> ET2UTC -->
UNITIM<br>
</div>
<div
>====================================================================<span
></span>============<br>
</div>
<div>See the instructions above for obtaining the correct format LSK
for your machine type.</div>
<div>Or, convert your file using either the dos2unix or the unix2dos
utility, as appropriate.</div>
<div>(These are available on many machines.)</div>
<div><br></div>
<div><br></div>
<div><br></div>
<div>Note to users of C and IDL versions of the Toolkit (CSPICE and
Icy)</div>
<div
>-------------------------------------------------------------------</div
>
<div>If you obtain Version N0060 of the Toolkit (available starting
12/23/2005), it will</div>
<div>not be required that the leapsecond kernel you acquire uses the
line termination</div>
<div>style native to your computer's operating system. New code in the
CSPICE and Icy</div>
<div>Toolkits will detect and account for the non-native text file
line termination.</div>
<div>Unfortunately this capability is NOT possible in FORTRAN Toolkits
(SPICELIB).</div>
<div><br></div>
<x-sigsep><pre>--
</pre></x-sigsep>
<div><br>
<br>
Charles.H.Acton@jpl.nasa.gov <span
></span
> <span
></span> Phone (818) 354-3869<br>
Navigation and Ancillary Information Group/JPL
Fax (818) 393-6388<br>
=====================================================================<span
></span>===========<br>
NAIF website: http://naif.jpl.nasa.gov<br>
SPICE news:
http://naif.jpl.nasa.gov/mailman/listinfo/spice_announce</div>
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