Recently discovered comets

The below table lists comets that have been discovered in the past 6 months.
For detailed information about a comet, click on its designation.

Comet(s) Today Perihelion Nearest approach
designation Hₒ magn delta radius date magn radius date magn delta
C/2017 U4 (PANSTARRS) AU7.97 AU3 Sep 201820.57.77 AU12 Dec 201820.16.82 AU
P/2017 U3 (PANSTARRS) AU4.63 AU21 Apr 201921.34.44 AU23 Dec 201820.63.52 AU
C/2017 U2 (Fuls) AU6.72 AU29 Aug 201720.86.70 AU29 Aug 201720.85.87 AU
1I/ʻOumuamua22.024.31.35 AU1.97 AU9 Sep 201721.40.25 AU15 Oct 201719.00.16 AU
C/2017 T3 (ATLAS) AU3.60 AU19 Jul 20189.40.83 AU1 Aug 20189.51.35 AU
C/2017 T2 (PANSTARRS) AU8.89 AU5 May 20208.31.61 AU29 Dec 20199.61.53 AU
C/2017 T1 (Heinze)12.515.61.38 AU1.85 AU21 Feb 201810.30.58 AU5 Jan 20189.60.22 AU
P/2017 S9 (PANSTARRS) AU2.32 AU23 Jul 201721.92.20 AU21 Nov 201721.11.39 AU
P/2017 S8 (PANSTARRS) AU1.78 AU28 Jan 201819.31.68 AU5 Nov 201718.80.90 AU
C/2017 S7 (Lemmon) AU7.69 AU27 May 201720.57.61 AU18 Dec 201620.06.70 AU
C/2017 S6 (Catalina)12.516.41.23 AU2.03 AU26 Feb 201816.81.54 AU27 Nov 201716.31.21 AU
P/2017 S5 (ATLAS) AU2.30 AU27 Jul 201718.52.18 AU7 Oct 201718.01.26 AU
C/2017 S3 (PANSTARRS) AU4.37 AU15 Aug 20183.50.21 AU7 Aug 20185.50.76 AU
C/2017 S2 (PANSTARRS) AU3.68 AU29 Aug 201720.83.61 AU7 Oct 201720.72.65 AU
P/2017 R1 (PANSTARRS)13.521.33.04 AU3.45 AU8 Apr 201721.73.33 AU9 Sep 201720.72.38 AU
C/2017 P2 (PANSTARRS) AU2.47 AU6 Dec 201716.32.46 AU19 Jul 201716.72.60 AU
P/2017 P1 (PANSTARRS) AU5.50 AU17 Jun 201821.05.44 AU13 Sep 201820.64.45 AU
C/2017 O1 (ASASSN1) AU1.59 AU14 Oct 20178.81.50 AU18 Oct 20178.80.72 AU
C/2017 M5 (TOTAS)6.518.56.78 AU6.14 AU2 Jun 201818.05.99 AU6 Aug 201817.85.04 AU
C/2017 M4 (ATLAS) AU5.04 AU18 Jan 201914.63.25 AU14 May 201913.82.48 AU
C/2017 M3 (PANSTARRS)10.521.15.36 AU4.93 AU28 Apr 201720.54.66 AU13 Mar 201821.04.44 AU
C/2017 K6 (Jacques) AU2.07 AU3 Jan 201814.92.00 AU17 Dec 201714.91.82 AU
C/2017 K5 (PANSTARRS) AU9.28 AU21 Mar 202020.37.68 AU2 Jul 202020.06.69 AU
C/2017 K4 (ATLAS) AU2.69 AU8 Jan 201817.02.65 AU3 Jul 201716.92.31 AU
P/2017 K3 (Gasparovic)14.521.53.32 AU2.75 AU31 May 201718.82.33 AU29 May 201718.81.33 AU
C/2017 K2 (PANSTARRS)1.519.015.18 AU15.02 AU21 Dec 20225.91.81 AU14 Jul 20226.91.83 AU
C/2017 K1 (PANSTARRS) AU7.32 AU15 Mar 201819.77.28 AU29 Apr 201819.66.28 AU

For possible comets still needing confirmation, see

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
    Hₒ:         Absolute magnitude (magnitude from a distance of 1 AU) 

Orbital elements provided by MPC (Minor Planet Center)
Observations contributed by observers worldwide, via COBS (Comet Observation Database).
UCAC4 star catalog and NGC2000 dso catalog via VizieR as provided by the Strasbourg astronomical Data Center.
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.