Bright comets in the coming 3 months

The below table lists all comets that are expected to become brighter than magnitude 15 in the coming 3 months.
For detailed information about a comet, click on its designation.

Comet(s) Today Perihelion Nearest approach
designation magn delta radius date magn radius date magn delta
C/2023 P1 (Nishimura)4.81.21 AU0.34 AU17 Sep 20232.50.23 AU12 Sep 20233.10.84 AU
2P/Encke10.00.90 AU0.74 AU22 Oct 20237.30.34 AU24 Sep 202310.10.90 AU
C/2020 V2 (ZTF)10.01.87 AU2.73 AU8 May 202310.32.23 AU17 Sep 20239.91.85 AU
103P/Hartley10.40.38 AU1.09 AU12 Oct 202310.41.06 AU26 Sep 202310.40.38 AU
C/2017 K2 (PANSTARRS)11.43.80 AU3.73 AU19 Dec 20228.41.80 AU14 Jul 20228.81.81 AU
C/2021 T4 (Lemmon)12.02.25 AU1.67 AU31 Jul 20239.01.48 AU20 Jul 20238.50.54 AU
C/2023 E1 (ATLAS)12.10.75 AU1.69 AU1 Jul 20239.61.03 AU18 Aug 20239.40.37 AU
C/2021 S3 (PANSTARRS)12.33.00 AU2.39 AU14 Feb 20248.71.32 AU14 Mar 20248.71.30 AU
29P/Schwassmann-Wachmann12.46.61 AU6.14 AU28 Apr 201912.25.78 AU9 Sep 201811.54.79 AU
62P/Tsuchinshan12.51.23 AU1.65 AU25 Dec 20237.21.26 AU29 Jan 20247.80.50 AU
C/2020 K1 (PANSTARRS)13.13.48 AU3.36 AU9 May 202312.23.07 AU9 Jun 202312.12.47 AU
C/2023 H2 (Lemmon)13.31.53 AU1.08 AU29 Oct 202310.00.89 AU10 Nov 20238.00.19 AU
C/2022 A2 (PANSTARRS)13.42.20 AU3.18 AU18 Feb 20239.71.74 AU17 Jan 20239.51.61 AU
144P/Kushida13.61.11 AU1.94 AU25 Jan 20249.01.40 AU12 Dec 20239.30.57 AU
C/2019 L3 (ATLAS)13.77.13 AU6.40 AU9 Jan 20229.43.55 AU6 Jan 20229.42.58 AU
C/2019 U5 (PANSTARRS)14.04.82 AU3.96 AU29 Mar 202312.33.62 AU24 Mar 202312.32.63 AU
237P/LINEAR14.31.63 AU2.24 AU14 May 202312.41.99 AU8 Jul 202312.21.06 AU
C/2022 JK5 (PANSTARRS)14.42.16 AU3.08 AU28 Apr 202314.52.69 AU21 Aug 202314.12.01 AU
185P/Petriew14.62.01 AU1.39 AU12 Jul 202312.30.93 AU21 Jun 202312.51.50 AU
12P/Pons-Brooks14.83.14 AU3.17 AU21 Apr 20244.20.78 AU2 Jun 20246.31.55 AU
C/2019 T4 (ATLAS)14.86.21 AU5.71 AU8 Jun 202212.14.24 AU4 Apr 202211.83.33 AU
C/2021 X1 (Maury-Attard)14.92.44 AU3.43 AU27 May 202315.73.23 AU25 Sep 202314.92.44 AU
126P/IRAS14.91.28 AU1.92 AU5 Jul 202314.51.71 AU18 Sep 202314.71.28 AU
C/2022 E2 (ATLAS)15.15.56 AU4.81 AU14 Sep 202413.23.67 AU1 Dec 202412.62.99 AU
C/2021 G2 (Atlas)15.36.46 AU5.65 AU9 Sep 202414.54.98 AU15 Apr 202413.94.24 AU
C/2023 A3 (Tsuchinshan-ATLAS)15.66.12 AU5.30 AU27 Sep 20240.20.39 AU12 Oct 2024-0.90.47 AU
13P/Olbers16.13.20 AU3.71 AU29 Jun 20247.51.18 AU19 Jul 20247.71.89 AU
32P/Comas Sola16.71.97 AU2.70 AU20 Apr 202414.72.02 AU29 Nov 202314.91.43 AU
321P/SOHO21.52.00 AU1.00 AU26 Oct 20236.10.05 AU28 Oct 20239.70.92 AU
26P/Grigg-Skjellerup21.72.36 AU1.57 AU25 Dec 202314.71.08 AU24 Dec 202314.71.80 AU

For each of the listed comets, the current position is plotted in the below all-sky chart:

    delta:      Distance between comet and earth in AU
    radius:     Distance between comet and sun in AU
    magn:       Magnitude (brightness) estimate    
    elong:      Elongation in degrees (angle sun-earth-comet)    
    AU:         Astronomical Unit (mean distance between earth and sun: 149597870.7 km
    Perihelion: On this date the comet (or other type of body) is closest to the sun

Orbital elements provided by MPC (Minor Planet Center).
Observations contributed by observers worldwide, via COBS (Comet Observation Database).
Calculations by a modified version of AAPlus, a C# implementation of the AA+ project by PJ Naughter from the algorithms presented in the book "Astronomical Algorithms" by Jean Meeus.
NGC2000 dso catalog and star labels from VizieR as provided by the Strasbourg astronomical Data Center.
Tycho2 catalog from the ESO archive.