Type Parabolic Perihelion Date 14 October 2017 Perihelion Distance (q) 1.5 Aphelion Distance (Q) n/a Period (Years) n/a Eccentricity (e) 1.0 Inclination (i) 39.8 Click for NASA orbit diagram

The All-Sky Automated Survey for Supernovae (ASASSN) discovered a 15th magnitude comet with the "Cassius" 14cm telescope at Cerro Tololo on 19 July 2017. Before the discovery announcement JJ Gonzalez had made a visual observation estimating the comet at 10th magnitude. It should become observable from the UK in early August and should be a binocular object over the late summer, autumn and early winter. Date 10x10 mag Error Kphot mag Coma ' 21-Jul-17 14.76 0.01 11.9 4.2 27-Jul-17 14.51 0.01 11.8 3.6 04-Aug-17 13.78 0.08 10.6 2.3 19-Aug-17 13.48 0.05 10.3 4.0 21-Aug-17 13.78 0.01 10.6 1.6 28-Aug-17 14.16 0.04 11.1 3.2 16-Sep-17 14.31 0.02 11.3 5.6 02-Oct-17 14.28 0.03 11.2 4.7 17-Oct-17 14.17 0.01 11.1 4.3 25-Oct-17 14.14 0.01 11.0 3.6 13-Nov-17 14.66 0.02 11.3 2.3 28-Nov-17 15.31 0.02 12.0 1.0 22-Dec-17 15.77 0.09 12.6 1.5 04-Jan-18 16.78 0.01 13.7 1.6 14-Jan-18 16.68 0.01 13.6 1.1 21-Jan-18 17.00 0.04 13.9 0.8 09-Feb-18 17.72 0.08 14.8 0.8 09-Mar-18 18.46 0.18 16.6 0.3 14-Mar-18 18.61 0.08 17.7 0.3

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