THE ASTROMETRIC RESULTS OF OBSERVATIONS OF PERIODICAL COMETS AT KT-50 TELESCOPE IN RI “MAO”

Анотація

The  astrometric  results  of  the observations  of  10  periodical  comets  in  2017  are presented.  The  observations  were  made  with  telescope KT-50  telescope  in  RI  «Mykolaiv  Astronomical Observatory». The differences between the measured from observations  (O)  and  calculated  from  ephemeris  (C) positions  and  their  mean  square  errors  (MSE)  were calculated. The ephemeris positions were taken from online computation service HORIZONS (JPL NASA, USA). For  the  measured  positions  the  average  MSE  values  are 0.17˝  in  right  ascension  and  0.18˝  in  declination respectively. Analysis of the values (О-C) before and after additions  of  obtained  positions  to  Minor  Planet  Center (MPC)  database  revealed  a  gradual  decrease  of  these differences  with  respect  to  the  ephemeris.  This  indicates that the using of the new high-precision positions allows us  to  refine  the  calculated  ephemeris.  As  well improvement and lengthening of the astrometric datasets play  important  role  in  the  modeling  of  the  cometary nongravitational effects.