A method of immediate detection of objects with a near-zero apparent motion in series of CCD-frames

¹ Western Radio Technical Surveillance Center, State Space Agency of Ukraine, Kosmonavtiv Street, 89600 Mukachevo, Ukraine
e-mail: vadym@savanevych.com
² Uzhhorod National University, Laboratory of space research, 2a Daleka Street, 88000 Uzhhorod, Ukraine
e-mail: sergii.khlamov@gmail.com
³ Main Astronomical Observatory of the NAS of Ukraine, 27 Akademika Zabolotnogo Street, 03143 Kyiv, Ukraine
⁴ Kharkiv National University of Radio Electronics, 14 Nauki Avenue, 61166 Kharkiv, Ukraine
⁵ National Astronomical Research Institute of Thailand, 260 Moo 4, T. Donkaew, A. Maerim, 50180 Chiangmai, Thailand
⁶ Institute of Physics, Faculty of Natural Sciences, University of P. J. Safarik, Park Angelinum 9, 04001 Kosice, Slovakia
⁷ Scientific Research, Design and Technology Institute of Micrographs, 1/60 Akademika Pidgornogo Street, 61046 Kharkiv, Ukraine
⁸ Department of Physics and Astronomy, University of North Carolina at Chapel Hill, Chapel Hill NC-27599, North Carolina, USA

Received: 22 December 2016
Accepted: 25 September 2017

Abstract

The paper deals with a computational method for detection of the solar system minor bodies (SSOs), whose inter-frame shifts in series of CCD-frames during the observation are commensurate with the errors in measuring their positions. These objects have velocities of apparent motion between CCD-frames not exceeding three rms errors (3σ) of measurements of their positions. About 15% of objects have a near-zero apparent motion in CCD-frames, including the objects beyond the Jupiter’s orbit as well as the asteroids heading straight to the Earth. The proposed method for detection of the object’s near-zero apparent motion in series of CCD-frames is based on the Fisher f-criterion instead of using the traditional decision rules that are based on the maximum likelihood criterion. We analyzed the quality indicators of detection of the object’s near-zero apparent motion applying statistical and in situ modeling techniques in terms of the conditional probability of the true detection of objects with a near-zero apparent motion. The efficiency of method being implemented as a plugin for the Collection Light Technology (CoLiTec) software for automated asteroids and comets detection has been demonstrated. Among the objects discovered with this plugin, there was the sungrazing comet C/2012 S1 (ISON). Within 26 min of the observation, the comet’s image has been moved by three pixels in a series of four CCD-frames (the velocity of its apparent motion at the moment of discovery was equal to 0.8 pixels per CCD-frame; the image size on the frame was about five pixels). Next verification in observations of asteroids with a near-zero apparent motion conducted with small telescopes has confirmed an efficiency of the method even in bad conditions (strong backlight from the full Moon). So, we recommend applying the proposed method for series of observations with four or more frames.