Electronic Telegram No. 5121 Central Bureau for Astronomical Telegrams Mailing address: Hoffman Lab 209; Harvard University; 20 Oxford St.; Cambridge, MA 02138; U.S.A. e-mail: cbatiau@eps.harvard.edu (alternate cbat@iau.org) URL http://www.cbat.eps.harvard.edu/index.html Prepared using the Tamkin Foundation Computer Network COMET C/2022 J1 (MAURY-ATTARD) Alain Maury reports that Georges Attard (Mougins, France) and he have discovered another comet on images obtained with a 0.28-m f/2.2 Schmidt reflector at San Pedro de Atacama, Chile, on May 5 (discovery astrometry tabulated below), with the object described as having a condensed 6" coma with an 18"-long tail spanning p.a. 220-260 degrees. 2022 UT R.A. (2000) Decl. Mag. Observer May 5.38566 21 25 24.73 -25 12 13.7 17.6 Maury 5.39133 21 25 24.09 -25 12 07.4 17.4 " 5.39706 21 25 23.45 -25 12 00.8 17.4 " After the comet was posted on the Minor Planet Center's PCCP webpage, other CCD astrometrists have also commented on the cometary appearance. Twelve stacked 60-s exposures taken remotely by K. Yoshimoto, Yamaguchi, Japan, using a 0.50-m f/6.8 reflector located at Siding Spring, NSW, Australia, on May 5.8 UT show a diffuse coma 22" in diameter (and total mag 17.7) and no tail. Ten stacked 60-s exposures taken remotely by M. Mattiazzo (Swan Hill, Victoria, Australia) with a 0.43-m astrograph located at Siding Spring on May 5.8 show a diffuse appearance; the GAIA DR2 magnitude was 18.1 as measured within a circular aperture of radius 4".9. Thirty stacked 60-s exposures taken by A. Aletti, F. Bellini, L. Buzzi, and G. Galli with a 0.36-m f/8.4 reflector at the Schiaparelli Southern Observatory, Hakos, Namibia, in good seeing conditions reveal a very condensed 4" coma and a diffuse outer coma 15" wide, with a broad faint tail at least 10" long in p.a. around 230 degrees. J. Chesley, Jet Propulsion Laboratory, found this comet independently in infrared images obtained during May 6.1-6.9 with the Near-Earth Object Wide- field Infrared Survey Explorer (or NEOWISE; formerly the WISE earth-orbiting satellite; cf. CBET 4225), describing it as showing a coma approximately 1' across at 4.6 microns. E. Bryssinck, Kruibeke, Belgium, writes that fifteen stacked, luminance-filtered 60-s exposures taken in poor conditions (high clouds) on May 6.4 with a "Telescope Live" 0.61-m f/6.5 reflector located at Rio Hurtado, Chile, show a diffuse coma of size about 12" and magnitude of 18.3-18.9 in an aperture radius of 5".5. Ten stacked 60-s exposures taken remotely by H. Sato (Tokyo, Japan) with a 0.51-m f/6.8 astrograph located at Siding Spring on May 6.79 show a strongly condensed object with an outer coma 65" in diameter and no tail; the magnitude was 16.4 as measured within a circular aperture of radius 32".9. Images taken by D. De Martin on May 7.0 with a 0.51-m f/6.8 Corrected Dall-Kirkham telescope located at the Skygems Remote Observatory in Namibia show a diffuse coma of diamter 6" and mag 18.6-18.9 with no tail. C. Jacques, Belo Horizonte, MG, Brazil, writes that one hundred stacked 30-s exposures obtained on May 8.2-8.3 with a 0.45-m reflector at the SONEAR Observatory, Oliveira, show a diffuse coma of diameter 30" and mag 17.6-18.4 and no tail. The available astrometry appears on MPEC 2022-J88. The following parabolic orbital elements by S. Nakano (Central Bureau) are from 96 observations spanning May 5-10 (mean residual 0".5). It is possible that the comet has a periodic orbit on the order of 120 years or so. T = 2022 Feb. 21.59780 TT Peri. = 307.65534 Node = 280.89097 2000.0 q = 1.6342449 AU Incl. = 106.42504 The following ephemeris by the undersigned from the above orbital elements uses photometric power-law parameters H = 13.5 and 2.5n = 8 for the magnitudes. Date TT R. A. (2000) Decl. Delta r Elong. Phase Mag. 2022 04 11 21 54.71 -32 15.3 1.973 1.758 62.8 30.5 16.9 2022 04 16 21 50.68 -30 53.9 1.907 1.783 67.5 31.3 16.9 2022 04 21 21 45.76 -29 30.8 1.837 1.810 72.5 32.0 16.9 2022 04 26 21 39.83 -28 04.9 1.766 1.839 77.9 32.3 16.9 2022 05 01 21 32.73 -26 35.2 1.693 1.870 83.5 32.4 16.8 2022 05 06 21 24.30 -25 00.2 1.621 1.902 89.6 32.0 16.8 2022 05 11 21 14.38 -23 18.6 1.550 1.936 96.0 31.2 16.7 2022 05 16 21 02.84 -21 28.8 1.482 1.972 102.9 30.0 16.7 2022 05 21 20 49.56 -19 29.4 1.420 2.008 110.2 28.2 16.7 2022 05 26 20 34.52 -17 19.2 1.366 2.046 117.8 26.0 16.7 2022 05 31 20 17.75 -14 58.2 1.321 2.084 125.9 23.2 16.7 2022 06 05 19 59.48 -12 27.6 1.289 2.124 134.1 20.1 16.7 2022 06 10 19 40.06 -09 50.1 1.271 2.164 142.1 16.7 16.7 2022 06 15 19 20.00 -07 10.5 1.269 2.206 149.5 13.5 16.8 2022 06 20 18 59.91 -04 34.2 1.285 2.248 155.2 10.9 16.9 2022 06 25 18 40.37 -02 07.1 1.317 2.290 157.8 9.7 17.0 2022 06 30 18 21.94 +00 06.1 1.366 2.334 156.5 10.0 17.1 2022 07 05 18 05.02 +02 02.5 1.430 2.378 152.3 11.5 17.3 2022 07 10 17 49.87 +03 41.0 1.507 2.422 146.6 13.4 17.5 2022 07 15 17 36.58 +05 02.3 1.597 2.467 140.4 15.2 17.7 2022 07 20 17 25.14 +06 07.9 1.695 2.512 134.2 16.9 17.8 2022 07 25 17 15.45 +06 59.7 1.802 2.557 128.1 18.2 18.0 2022 07 30 17 07.39 +07 40.0 1.915 2.603 122.3 19.2 18.2 2022 08 04 17 00.80 +08 10.7 2.033 2.649 116.7 20.0 18.4 2022 08 09 16 55.53 +08 33.8 2.155 2.696 111.4 20.5 18.6 2022 08 14 16 51.42 +08 50.8 2.279 2.742 106.4 20.8 18.8 2022 08 19 16 48.34 +09 03.0 2.405 2.789 101.5 20.8 19.0 2022 08 24 16 46.15 +09 11.4 2.532 2.836 96.9 20.7 19.1 2022 08 29 16 44.75 +09 17.1 2.659 2.883 92.4 20.5 19.3 2022 09 03 16 44.06 +09 20.7 2.785 2.930 88.1 20.1 19.5 2022 09 08 16 43.98 +09 23.0 2.911 2.978 83.9 19.7 19.6 2022 09 13 16 44.43 +09 24.4 3.035 3.025 79.9 19.1 19.8 2022 09 18 16 45.35 +09 25.4 3.157 3.072 76.0 18.5 19.9 NOTE: These 'Central Bureau Electronic Telegrams' are sometimes superseded by text appearing later in the printed IAU Circulars. (C) Copyright 2022 CBAT 2022 May 11 (CBET 5121) Daniel W. E. Green