Speaker
Description
The Taurid Complex is a large interplanetary system that contains comet 2P/Encke, several meteoroid streams, and possibly a number of near-Earth asteroids [1]. The size and nature of the system have led to the speculation that it was formed through a large-scale cometary breakup [2]. Numerical investigations and meteor observations have suggested that planetary dynamics can create a resonant region with a large number of objects concentrated in a small segment of the orbit, known as the Taurid swarm, which approaches the Earth in certain years and provides favorable conditions to study the Taurid Complex [3,4,5].
Here we report a dedicated telescopic search for potentially hazardous asteroids and other macroscopic objects in the Taurid swarm using the 1.2-m Palomar Schmidt telescope as part of the Zwicky Transient Facility survey [6]. Observations were made on October 29 and 31, 2022, when the Earth passed close to the center of the Taurid swarm. We imaged an on-sky area of 1550 square degrees covering 99% of 100-m-class swarm objects. Two sets of moving object detection software were used to search for swarm objects, one specialized in detecting fast-moving, trailed objects and the other focused on point-source objects [7,8], with no swarm objects found. We determine from our non-detection that there are no more than 9-14 H<24 (equivalent to a diameter of D≳100 m) objects in the swarm, suggesting that the Encke-Taurid progenitor was ~10 km in size. A progenitor of such a size is compatible with the prediction of state-of-the-art Solar System dynamical models, which expect ~0.1 D>10 km objects on Encke-like orbits at any given time. We will also discuss the implications of our results for the existence of smaller, Tunguska-sized objects in the swarm, also discussed by Boslough et al. at this conference [9].
This work is supported by NASA program 80NSSC22K0772. DV and DLC are in part supported by NASA Meteoroid Environment Office under cooperative agreement 80NSSC24M0060. Based on observations obtained with the Samuel Oschin Telescope 48-inch and the 60-inch Telescope at the Palomar Observatory as part of the Zwicky Transient Facility project. ZTF is supported by the National Science Foundation under Grant No. AST-2034437 and a collaboration including Caltech, IPAC, the Weizmann Institute of Science, the Oskar Klein Center at Stockholm University, the University of Maryland, Deutsches Elektronen-Synchrotron and Humboldt University, the TANGO Consortium of Taiwan, the University of Wisconsin at Milwaukee, Trinity College Dublin, Lawrence Livermore National Laboratories, IN2P3, University of Warwick, Ruhr University Bochum, Cornell University, and Northwestern University. Operations are conducted by COO, IPAC, and UW.
Reference:
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