This directory contains the Deep Impact observations of comet Tempel 1
obtained on 2005 July 04 UT. The observations were made with the High Resolution
Echelle Spectrometer (HIRES) at the W. M. Keck Observatory (WMKO). One 
12 min pre-impact exposure was made during twilight. Due to the brightness of 
the sky, this spectrum was entirely dominated by sky.  Thirteen post-impact 
exposures ranging from 10 to 30 min were obtained for the comet nucleus. 
Due to a telescope fault at the precise moment of impact (05:52 UT), an 
exposure spanning the time of the actual impact was lost. The log of the 
observations is in "log.txt".

The instrumental setup for these observations, which were made with the HIRES
blue cross disperser, is:
DECKNAME: C1  (7" x 0.861" slit)
XDANGLE:  0.982
ECHANGL:  0.00
BINNING:  2x1 (binned by 2 in the spatial direction)
CCDGAIN:  low

The spectra cover approximately 3000A - 5900A.

No filters were used for the objects (Tempel 1 and standard stars), but a UG5 
was used for the flats and NG3 was used for the arcs (Thorium-Argon).  

In addtion to the data FITS files, the following supplementary files are also
provided:
  K1_Nightlog_04_July_05_(UT).txt  - Night log from the night's observing assistant
  tempel1_20050704_cam[00-15].fits  - Guider images during the comet exposures
  tempel1_20050704_06:04UT.jpg  - Screen snapshots of the guider camera display
  tempel1_20050704_07:16UT.jpg 
  tempel1_20050704_09:10UT.jpg
            
These data are made available through the Keck Observatory Archive (KOA), and 
can be downloaded from:

  http://msc.caltech.edu/deepimpact

For further information about KOA, HIRES and WMKO, visit:

  http://msc.caltech.edu/koa
    or 
  http://www2.keck.hawaii.edu/realpublic/koa/public/koa.php.

The Keck Observatory Archive has been made possible by funding provided by 
the National Aeronautics and Space Administration to Caltech and the 
W. M. Keck Observatory. The W. M. Keck Observatory Director Fred Chaffee is 
thanked for donating his director's time for the HIRES observations of Tempel 1 
and for providing the data to the public.