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/2020 S3 (Erasmus)6.21.12 AU0.49 AU12 Dec 20205.60.40 AU18 Nov 20207.71.04 AU
C/2020 M3 (ATLAS)8.70.40 AU1.38 AU25 Oct 20208.41.27 AU14 Nov 20208.20.36 AU
88P/Howell11.31.82 AU1.53 AU26 Sep 20209.21.35 AU10 May 202013.21.08 AU
156P/Russell-LINEAR11.40.59 AU1.34 AU17 Nov 202011.01.33 AU23 Oct 202011.20.48 AU
10P/Tempel12.42.79 AU1.81 AU24 Mar 20219.11.41 AU3 Nov 202114.71.61 AU
C/2019 N1 (ATLAS)12.42.40 AU1.70 AU1 Dec 202012.41.70 AU8 Feb 202112.31.91 AU
C/2017 T2 (PANSTARRS)13.04.08 AU3.10 AU4 May 20208.61.62 AU28 Dec 20199.81.52 AU
29P/Schwassmann-Wachmann13.14.97 AU5.84 AU19 Mar 201913.75.77 AU9 Sep 201812.94.77 AU
C/2020 P1 (NEOWISE)13.91.70 AU1.11 AU20 Oct 20206.30.34 AU12 Oct 20206.50.66 AU
398P/Boattini14.00.40 AU1.34 AU26 Dec 202013.71.31 AU22 Dec 202013.70.38 AU
141P/Machholz14.00.91 AU0.84 AU16 Dec 202013.20.81 AU19 Jan 202114.10.53 AU
246P/NEAT14.13.86 AU2.90 AU22 Feb 202113.52.86 AU1 Jul 202112.81.94 AU
C/2019 L3 (ATLAS)14.34.48 AU5.03 AU9 Jan 202211.33.55 AU6 Jan 202211.32.58 AU
28P/Neujmin14.32.86 AU1.97 AU11 Mar 202112.71.58 AU6 Nov 202116.62.22 AU
C/2020 F3 (NEOWISE)14.43.83 AU2.86 AU3 Jul 20201.10.29 AU23 Jul 20203.30.69 AU
C/2017 K2 (PANSTARRS)14.68.12 AU7.67 AU19 Dec 20226.31.80 AU14 Jul 20227.11.81 AU
162P/Siding Spring14.80.93 AU1.29 AU7 Dec 202014.91.29 AU27 Oct 202014.90.87 AU
C/2020 F5 (MASTER)14.94.98 AU4.42 AU24 Mar 202114.84.33 AU21 Aug 202114.33.57 AU
C/2019 T4 (ATLAS)15.05.93 AU6.15 AU9 Jun 202211.04.24 AU4 Apr 202210.73.33 AU
C/2020 J1 (SONEAR)15.34.46 AU3.59 AU18 Apr 202113.83.36 AU16 May 202113.62.37 AU
283P/Spacewatch15.52.24 AU3.01 AU8 Sep 202114.72.13 AU25 Jan 202114.71.84 AU
C/2019 F1 (ATLAS-Africano)15.64.92 AU4.03 AU22 Jun 202114.33.60 AU21 Jun 202114.33.05 AU
C/2020 N1 (PANSTARRS)16.41.33 AU1.95 AU12 Mar 202114.91.32 AU3 Feb 202115.11.23 AU
6P/d'Arrest16.73.72 AU3.05 AU17 Sep 20219.91.35 AU2 Aug 202110.00.75 AU
C/2020 R4 (ATLAS)17.21.76 AU1.76 AU1 Mar 202114.81.03 AU23 Apr 202113.10.46 AU
7P/Pons-Winnecke17.72.55 AU2.29 AU27 May 202111.31.23 AU12 Jun 202111.30.44 AU
323P/SOHO22.11.56 AU1.31 AU17 Jan 20216.00.04 AU7 Feb 202116.90.44 AU
P/2010 H3 (SOHO)23.12.44 AU1.67 AU7 Feb 202112.10.04 AU8 Feb 202112.70.94 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.