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KStars keeps track of thousands of comets and asteroids.
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It uses orbital data published by NASA's Jet Propulsion
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Laboratory (JPL); these data are known as "orbital elements".
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Because these small bodies are easily perturbed as they
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wander about the solar system, their orbital elements must
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be updated regularly. Updating the elements will also add
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any recently-discovered bodies.
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How to update the orbital elements of comets and asteroids:
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-=( 1 )=- The Easy Way.
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Start KStars, then open the "Get New Stuff" Tool by selecting
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"Download Data..." from the File menu, or by pressing Ctrl+D.
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If a new "ephemerides" package is available, select it and press
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the Install button. Voila!
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If the "ephemerides" package available from the "Get New Stuff"
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Tool is too old, you can use the menu items under
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"Settings" > "Updates" to download the last ephemerides from
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NASA's Jet Propulsion Laboratory website.
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-=( 2 )=- Doing it Manually.
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It is possible that the ephemerides package is not completely
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up-to-date. Fortunately, it's relatively simple to update the
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files manually whenever you want.
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::NOTE:: If you find that the ephemerides package is woefully
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outdated, and you follow this manual-install procedure, PLEASE
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send your final comets.dat and asteroids.dat files to
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kstars-devel@kde.org! Now is your chance to be a KStars Hero!
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You can use the following command to download comets.dat file
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wget -O comets.dat --post-data="obj_group=all&obj_kind=com&obj_numbered=all&OBJ_field=0&OBJ_op=0&OBJ_value=&ORB_field=0&ORB_op=0&ORB_value=&combine_mode=AND&c1_group=OBJ&c1_item=Af&c1_op=!%3D&c1_value=D&c2_group=OBJ&c2_item=Ae&c2_op=!%3D&c2_value=SOHO&c_fields=AcBdBiBgBjBlBkBqBbAiAjAgAkAlApAqArAsBsBtCh&table_format=CSV&max_rows=10&format_option=full&query=Generate%20Table&.cgifields=format_option&.cgifields=field_list&.cgifields=obj_kind&.cgifields=obj_group&.cgifields=obj_numbered&.cgifields=combine_mode&.cgifields=ast_orbit_class&.cgifields=table_format&.cgifields=ORB_field_set&.cgifields=OBJ_field_set&.cgifields=preset_field_set&.cgifields=com_orbit_class" http://ssd.jpl.nasa.gov/sbdb_query.cgi
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Delete or comment (with a '#') the first line.
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Finally, copy your modified "comets.dat" to
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~/.kde/share/apps/kstars/ (for a single-user install) or
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$KDEDIR/share/apps/kstars/ (for a system-wide install).
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You can use the following command to download asteroids.dat
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file from JPL website :
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wget -O asteroids.dat --post-data="obj_group=all&obj_kind=ast&obj_numbered=num&OBJ_field=0&ORB_field=0&c1_group=OBJ&c1_item=Ai&c1_op=%3C&c1_value=12&c_fields=AcBdBiBhBgBjBlBkBmBqBbAiAjAgAkAlApAqArAsBsBtCh&table_format=CSV&max_rows=10&format_option=full&query=Generate%20Table&.cgifields=format_option&.cgifields=field_list&.cgifields=obj_kind&.cgifields=obj_group&.cgifields=obj_numbered&.cgifields=combine_mode&.cgifields=ast_orbit_class&.cgifields=table_format&.cgifields=ORB_field_set&.cgifields=OBJ_field_set&.cgifields=preset_field_set&.cgifields=com_orbit_class" http://ssd.jpl.nasa.gov/sbdb_query.cgi
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Delete or comment (with a '#') the first line.
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Finally, copy your modified "asteroids.dat" to
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~/.kde/share/apps/kstars/ (for a single-user install) or
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$KDEDIR/share/apps/kstars/ (for a system-wide install).
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-=( 3 )=- Another way.
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The last method is to point your browser to the following
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http://ssd.jpl.nasa.gov/sbdb_query.cgi
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and generate the file using the form
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You must select the following columns to make the file
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compatible with kstars :
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2 modified julian day of orbital elements
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4 eccentricity of orbit
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5 inclination angle of orbit in degrees
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6 argument of perihelion in degrees
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7 longitude of the ascending node
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8 time of perihelion passage
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12 Near-Earth Object (NEO) flag
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13 comet total magnitude parameter
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14 comet nuclear magnitude parameter
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16 object bi/tri-axial ellipsoid dimensions
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20 earth minimum orbit intersection distance
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21 orbit classification
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2 Modified Julian Day of orbital elements
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3 perihelion distance
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5 eccentricity of orbit
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6 inclination angle of orbit in degrees
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7 argument of perihelion in degrees
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8 longitude of the ascending node in degrees
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10 time of perihelion passage
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12 absolute magnitude
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14 Near-Earth Object (NEO) flag
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15 comet total magnitude parameter
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16 comet nuclear magnitude parameter
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18 object bi/tri-axial ellipsoid dimensions
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22 earth minimum orbit intersection distance
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23 orbit classification
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The advantage of this method is that you can play with
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several filters and get a file containing exactly what
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Don't forget to delete or comment (with a '#') the first
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Finally, copy your files to
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~/.kde/share/apps/kstars/ (for a single-user install) or
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$KDEDIR/share/apps/kstars/ (for a system-wide install).