How can I obtain STK-compatible SPICE files for comets, asteroids, and other small bodies?

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QuestionHow can I obtain STK-compatible ephemeris files for comets, asteroids, and other small bodies?
The NASA JPL website, Horizons, allows you to build STK-compatible SPICE files for comets, asteroids, and other small bodies. The following instructions will walk you through this process.
The Horizons system does not offer STK-compatible ephemeris files for planetary moons. However, such files are available from another source. Refer to the following FAQ for planetary moons: How do I obtain STK-compatible ephemeris for planetary moons that are not already modeled in STK?
Using the Horizons system
1. Go to the following website:
2. Scroll down to the "Using the telnet Interface" section and click on the hyperlink:
(If an External Protocol Request dialog box appears, click Launch application)
A DOS prompt will appear showing the following:
      JPL Horizons, vers SUN-v3.32b
      Type `?' for brief intro, `?!' for more details
      System news updated Nov 13, 2007
3. At the prompt, type the common name, small space body designation name, or SPICE ID number at the prompt. For example:
Horizons> 2004 MN4
The following response will appear:
      >EXACT< designation search [CASE & SPACE sensitive]:
        DES = 2004 MN4;
      Continue [ =yes, n=no, ? ] :
4. Press the Enter key to search for the body.
The search results should be similar to the following:
      JPL/HORIZONS              99942 Apophis (2004 MN4)         2007-Dec-11 08:09:00
      Rec #: 99942 (+COV) 2006-Sep-01_00:50:35    # obs: 738 (2004-2006)
      FK5/J2000.0 helio. ecliptic osc. elements (AU, DAYS, DEG, period=Julian yrs):
        EPOCH=  2453442.5 ! 2005-Mar-13.00 (CT)         Residual RMS= .30901
          EC= .191054853916459   QR= .7461531666439291  TP= 2453600.734981114
          OM= 204.4721548004914  W= 126.3839706419199   IN= 3.330920734685656
          A= .9223779514054623   MA= 183.94709163245    ADIST= 1.098602736166995
          PER= .88587            N= 1.112604224         ANGMOM= .016216656
          DAN= 1.0023            DDN= .7982399999999999 L= 330.9024012
          B= 2.6810584                                  TP= 2005-Aug-18.2349811
      Physical parameters (KM, SEC, rotational period in hours):
          GM= n.a.               RAD= .135              ROTPER= n.a.
          H= 19.7                G= .250                B-V= n.a.
                           ALBEDO= .330           STYP= n.a.
      ASTEROID comments:
      1: soln ref.= JPL#139, PHA  OCC=0       radar( 2 delay, 5 Dop.)
      2: source=ORB
       Select ... [A]pproaches, [E]phemeris, [F]tp,[M]ail,[R]edisplay, [S]PK,?,:
5. STK-compatible SPICE files are created using the "[S]PK" option. Enter S to create a SPICE file.
Select ... [A]pproaches, [E]phemeris, [F]tp,[M]ail,[R]edisplay, [S]PK,?,: S
The following response will appear:
       Assigned SPK object ID:  2099942
       Enter your Internet e-mail address [?]:
6. Enter and confirm your e-mail address.
       Enter your Internet e-mail address [?]:
       Confirm e-mail address [yes(),no] :
The following response will appear.
       Address stored this login only ... use "email" cmd to change
       SPK text transfer format  [ YES, NO, ? ] :
7.  SPICE files in the text transfer format are not compatible with STK; they must be binary files. Enter No at this prompt.
       SPK text transfer format  [ YES, NO, ? ] : No
The following response will appear:
       SPK object START [ t >= 1900-Jan-01, ? ] :
8. Type in the Start and Stop times for your Spice file in the appropriate date format.
       SPK object START [ t >= 1900-Jan-01, ? ] : 2008-Jan-01
       SPK object STOP  [ t <= 2101-Jan-01, ? ] : 2009-Jan-01
A response similar to the following will appear:
         Chebyshevs constructed on STANDARD mesh.
         Current integration step:
          2454829.81537  2008 Dec 29.31537     2.6508021

          Binary SPK file created.
          A-posteriori SPK fidelity estimate (rel. to integrator):
               Max. error (3 std. dev)            Time
               ------------------------ ------------------------
            X: 0.6908704060214330D-04 m 2008-Sep-29 03:00:00.000
            Y: 0.8218709696074995D-04 m 2008-Jul-11 03:00:00.000
            Z: 0.4723960730105999D-04 m 2008-Jul-11 03:00:00.000
            RSS: 0.1173001218411825D-03 m 2008-Sep-29 03:00:00.000

            Add more objects to file  [ YES, NO, ? ] :
9. Enter No when asked if you would like to add additional objects.
                               Add more objects to file  [ YES, NO, ? ] : No
A response similar to the following will appear:
            You have 30 minutes to retrieve the following by anonymous FTP:
              Machine name:
              Directory   :  cd to "/pub/ssd/"
              File name   :  wld26489.15
              File type   :  BINAR

10. Rename the return file so that it has a .bsp extension.
              File name   :  wld26489.bsp
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