Weekly Information about Bright Comets (2020 May 9: South)

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Updated on May 9, 2020
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Best time and the azimuth, altitude (A,h) are at lat. 35 deg in the Southern Hemisphere.
Azimuth indicates 0 for south, 90 for west, 180 for north, 270 for east.

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* C/2020 F8 ( SWAN )

It brightened up to 4.7 mag in early May (May 2, Marco Goiato). However, the brightness evolution has stopped after that. Now it is 5.5 mag (May 8, Marco Goiato). It will approach to Sun down to 0.43 a.u. on May 27, and it was expected to brighten up to 3.5 mag. But actually it may be 5 mag at best. In the Southern Hemisphere, it is observable until mid May. In the Northern Hemisphere, it is only visible in extremely low sky in late May. Then it appears in the morning sky at 11 mag in August. And it will be observable in good condition after that while the comet will be fading.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9   0 49.77    4 12.9   0.577   0.635    35    3.8   5:16 (253, 17)  
May  16   2  5.10   29  9.4   0.579   0.523    22    3.0   5:20 (239, -7)  

* C/2019 U6 ( Lemmon )

Now it is very bright as 9.3 mag (Apr. 25, Chris Wyatt). Brightening very rapidly. It will approach to Sun down to 0.9 a.u. in June, and it is extected to brighten up to 5.5 mag. In the Southern Hemisphere, it stays observable in good condition for a long time after this. In the Northern Hemisphere, it is not observable until late June.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9   5 33.75  -21 55.7   1.428   1.162    53    8.6  18:36 ( 86, 34)  
May  16   5 56.36  -21 31.5   1.323   1.092    53    7.9  18:32 ( 86, 34)  

* C/2017 T2 ( PanSTARRS )

Now it is 8.5 mag (Apr. 29, Charles S. Morris). It stays bright as 8-9 mag until July. It is observable in good condition in the Northern Hemisphere. In the Southern Hemisphere, it is not observable until late June.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9   7 47.41   75 49.2   1.685   1.616    68    8.1  18:36 (173,-22)  
May  16   9  0.83   73 48.7   1.670   1.622    69    8.1  18:32 (175,-19)  

* C/2020 F3 ( NEOWISE )

Now it is very bright as 10.3 mag (Apr. 25, Chris Wyatt). It will approach to Sun down to 0.3 a.u. on July 3, and it is expected to brighten up to 2.5 mag. In the Southern Hemisphere, it stays observable in good condition until early June when it brightens up to 8 mag. But it will not be observable around the perihelion passage. In the Northern Hemisphere, it is not observable now. It will appear in the evening sky at 3-4 mag in mid July, then it stays observable while getting fainter.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9   6  8.12  -17 30.7   1.624   1.369    57    9.9  18:36 ( 95, 39)  
May  16   6  6.24  -12 41.4   1.626   1.238    49    9.5  18:32 ( 96, 31)  

* C/2019 Y4 ( ATLAS )

Now it is 9.0 mag (Apr. 29, Charles S. Morris). The nucleus was split into some fragments in late March, and the brightness evolution stopped. It brightened up to 7.0 mag in late March ((Mar. 30, Charles S. Morris). However, it is fading now. It moves along the same orbit as C/1844 Y1 (Great Comet). It approaches to Sun down to 0.25 a.u. on May 31. It was expected to brighten up to -1 mag. But it may disappear before the perihelion passage. In the Northern Hemisphere, it is observable until mid May. In the Southern Hemisphere, it is not observable until June.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9   4 46.59   55 29.4   0.868   0.698    42    9.7  18:36 (144,-21)  
May  16   4 17.64   49 19.2   0.816   0.532    31    9.7  18:32 (134,-25)  

* 58P/Jackson-Neujmin

Recovered from SWAN images after 24-year blank. Now it is very bright as 10.4 mag (Apr. 28, Chris Wyatt). It stays 10-11 mag until August. In the Southern Hemisphere, it stays observable in the morning sky for a long time. In the Northern Hemisphere, it is too low to observe until July.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9   0 42.31    3 32.1   2.054   1.395    37   10.2   5:16 (252, 18)  
May  16   1  5.89    5  6.0   2.029   1.384    38   10.1   5:20 (249, 19)  

* C/2019 Y1 ( ATLAS )

Now it is very bright as 8.8 mag (Apr. 28, Carlos Labordena). It continues brightening even after the perihelion passage on Mar. 15. It stays observable for a long time in the Northern Hemisphere. In the Southern Hemisphere, it is not observable until June when it fades down to 13-14 mag. It seems to be a fragment of C/1988 A1 (Liller), like C/1996 Q1 (Tabur) and C/2015 F3 (SWAN).

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9   9 26.25   77 53.5   1.118   1.286    74   10.4  18:36 (179,-22)  
May  16  10 39.68   68 28.5   1.160   1.375    78   11.2  19:05 (180,-13)  

* 2P/Encke

It will approach to Sun down to 0.34 a.u. and brighten up to 7 mag in June. In the Southern Hemisphere, it will appear in the evening sky at 7 mag in early July. Then it stays observable in good condition while the comet will be fading. In the Northern Hemisphere, it is not observable until mid August when the comet will fade down to 12 mag.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9   2 40.12   21 27.4   2.085   1.091     7   12.3   5:16 (254,-15)  
May  16   3  5.91   23  9.5   1.971   0.976     7   11.7   5:20 (252,-15)  

* 88P/Howell

Now it is 14.2 mag (Apr. 24, Chris Wyatt). Brightening very rapidly. It will brighten up to 8-9 mag from summer to autumn. It will be observable in excellent condition in the Southern Hemisphere. It locates very low around the high light in the Northern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9  12 49.21   -1 17.4   1.080   1.983   143   12.8  21:38 (180, 56)  
May  16  12 44.12   -1 12.3   1.083   1.936   135   12.6  21:06 (180, 56)  

* C/2020 H2 ( Pruyne )

Bright new comet. Now it is 13.2 mag (Apr. 28, Alan Hale). It will fade out rapidly after this, and it will be fainter than 18 mag in late June. It stays observable in good condition in the Northern Hemisphere. It will be unobservable after this in the Southern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9  23  8.89   52 53.8   0.658   0.861    57   13.4   5:16 (204, -5)  
May  16   0 35.64   73 54.8   0.730   0.902    59   13.9   5:20 (195,-25)  

* C/2019 N1 ( ATLAS )

Now it is 14.3 mag (Apr. 22, Sandor Szabo). It will brighten up to 10.5 mag from 2020 December to 2021 January. In the Northern Hemisphere, it stays observable in good condition while the comet will be brightening gradually, but it is not observable at the high light. In the Southern Hemisphere, it is not observable for a long time, but it will be observable in good condition after the high light.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9  14 27.81   79 36.2   3.020   3.064    82   13.8  23:10 (180,-24)  
May  16  13 33.03   77 58.3   2.978   2.999    81   13.6  21:50 (180,-23)  

* C/2018 N2 ( ASASSN )

Now it is 13.3 mag (Apr. 20, Sandor Szabo). It stays bright as 13 mag until June. In the Southern Hemisphere, it will never be observable again.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9   1 16.32   64 20.6   4.129   3.572    50   13.7   5:16 (207,-25)  
May  16   1 27.39   66 31.2   4.146   3.604    51   13.8   5:20 (204,-24)  

* 29P/Schwassmann-Wachmann 1

Now it is not observable. It will appear in the morning sky in June.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9   1 54.22   20  7.0   6.760   5.801    16   13.9   5:16 (249, -6)  
May  16   1 59.74   20 39.3   6.730   5.802    21   13.9   5:20 (245, -1)  

* 249P/LINEAR

Now it is 17.9 mag (Apr. 20, Thomas Lehmann). It will brighten rapidly, and it is expected to brighten up to 9.5 mag in June. But actually, it has not started brightening rapidly yet. It is not observable in June. However, it stays observable in good condition until May while the comet is brightening, and after July while the comet will be fading.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9   9  1.67    5 10.5   0.508   1.112    87   14.8  18:36 (163, 48)  
May  16   8 43.99    8 37.6   0.488   1.010    75   14.0  18:32 (151, 42)  

* 246P/NEAT

Now it is 14.2 mag (Apr. 14, Sandor Szabo). It stays 13-14 mag from 2020 to 2021. It stays observable in good condition for a while.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9  12 33.82   16 56.3   2.502   3.239   129   14.2  21:23 (180, 38)  
May  16  12 31.71   16 23.5   2.557   3.224   123   14.2  20:53 (180, 39)  

* 210P/Christensen

Now it is 11.4 mag (Apr. 22, Sandor Szabo). It will fade out rapidly after this, and will be fainter than 18 mag in June.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9   6 20.42   30 21.8   1.082   0.825    46   14.7  18:36 (138,  9)  
May  16   7 16.42   30 33.2   1.103   0.926    51   15.6  18:32 (143, 13)  

* C/2018 F4 ( PanSTARRS )

Now it is bright as 13.9 mag (Apr. 24, Chris Wyatt). It stays 15 mag until summer. It stays observable for a long time in the Southern Hemisphere. It is not observable until August in the Northern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9   2 43.39  -39 53.7   4.176   3.731    57   14.8   5:16 (306, 18)  
May  16   2 49.51  -38 47.3   4.181   3.757    58   14.9   5:20 (303, 22)  

* C/2019 F1 ( ATLAS-Africano )

Now it is 15.3 mag (Apr. 25, Hiroshi Abe). It will brighten up to 13 mag in 2021. In 2020, it is observable at 15 mag in good condition from spring to summer.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9  14 24.43  -20 21.1   4.088   5.085   170   15.1  23:13 (180, 75)  
May  16  14 18.84  -20 38.8   4.070   5.044   162   15.1  22:40 (180, 76)  

* C/2020 F5 ( MASTER )

Now it is 15.4 mag (Apr. 22, Chris Wyatt). It stays 14-15 mag until 2021. In the Southern Hemisphere, it stays observable in good condition for a long time. In the Northern Hemisphere, it is not observable until June in 2021.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9  16 59.85  -83 18.0   4.574   5.057   113   15.3   1:57 (  0, 42)  
May  16  16 42.91  -83 55.7   4.518   5.028   114   15.3   1:13 (  0, 41)  

* C/2017 K2 ( PanSTARRS )

Now it is 15.7 mag (Apr. 20, Sandor Szabo). It is expected to be observable at 5-6 mag for a long time from 2022 to 2023. In the Northern Hemisphere, it is not observable at the high light from 2022 summer to 2023 summer. In the Southern Hemisphere, it is only visible in the extremely low sky in summer in 2020. But it will be observable in good condition at the high light.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9  18  8.60   52 31.5   8.987   9.209    99   15.4   3:01 (180,  2)  
May  16  18  4.88   52 52.2   8.915   9.159   100   15.4   2:29 (180,  2)  

* C/2019 K7 ( Smith )

Now it is 15.9 mag (Apr. 21, Catalina Sky Survey). It stays 15-16 mag for a long time until 2021.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9  20 50.53    4 52.3   4.339   4.486    91   15.7   5:16 (190, 50)  
May  16  20 47.46    6 23.2   4.223   4.483    98   15.6   5:12 (180, 49)  

* P/2003 T12 = P/2012 A3 ( SOHO )

It brightens up to 16 mag in May. But it is not observable in this apparition. It has been observed at three apparitions in 2003, 2012 and 2016.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9   2 55.07   13 37.7   1.599   0.597     4   15.9   5:16 (263,-14)  
May  16   3 41.62   15 44.4   1.626   0.622     4   16.4  18:32 (100,-14)  

* C/2018 U1 ( Lemmon )

Now it is 17.1 mag (Apr. 23, D. Buczynski). It will stay at 14 mag for a long time from 2021 to 2022. In the Northern Hemisphere, it stays observable in good condition while brightening gradually. In the Southern Hemisphere, it stays locating low for a long time.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9  19  3.81   33 54.8   6.139   6.448   103   16.1   3:56 (180, 21)  
May  16  18 59.43   34 10.2   6.041   6.416   107   16.0   3:24 (180, 21)  

* C/2020 J1 ( SONEAR )

New comet. Now it is 16.5 mag (May 4, E. Guido, A. Valvasori). It will brighten up to 13.5 mag in spring in 2021. In the Southern Hemisphere, it stays observable in good condition for a long time. In the Northern Hemisphere, it is not observable until spring in 2021.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9  22 43.95  -49 33.0   4.452   4.532    88   16.3   5:16 (310, 61)  
May  16  22 42.76  -50 47.4   4.302   4.489    94   16.2   5:20 (317, 65)  

* C/2017 B3 ( LINEAR )

It brightened up to 13.8 mag in autumn in 2019 (Sept. 3, Chris Wyatt). Now it is fading slowly. It is appearing in the morning sky in the Southern Hemisphere. It will appear in June also in the Northern Hemisphere. In 2020, it stays observable in good condition while the comet will be fading from 16 to 17 mag.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9   0 25.15   -5 20.9   6.175   5.514    45   16.3   5:16 (257, 27)  
May  16   0 28.38   -4 36.7   6.133   5.553    50   16.3   5:20 (251, 32)  

* 115P/Maury

Now it is 17.6 mag (Mar. 22, Toshihiko Ikemura, Hirohisa Sato). It will brighten up to 15.5 mag from June to August, and it will be observable in good condition.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9  19 12.55   -5 16.6   1.505   2.173   118   16.4   4:05 (180, 60)  
May  16  19 17.57   -4 19.4   1.429   2.154   123   16.3   3:42 (180, 59)  

* C/2018 A6 ( Gibbs )

It brightened up to 13.2 mag from spring to autumn in 2019 (June 30, Thomas Lehmann). Now it is fading slowly. It has already faded down to 16.0 mag (Apr. 25, iTelescope Observatory, Siding Spring). In the Southern Hemisphere, it stays observable for a long time. In the Northern Hemisphere, it is not observasble until June.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9   0  5.53  -31 52.9   4.280   3.965    65   16.3   5:16 (282, 44)  
May  16   0  8.09  -31 22.2   4.229   4.002    70   16.4   5:20 (279, 50)  

* C/2019 L3 ( ATLAS )

Now it is 16.2 mag (Apr. 22, D. Buczynski). It will brighten up to 12 mag in winter in 2022. In the Northern Hemisphere, it stays observable in good condition for a long time. In the Southern Hemisphere, it is not observable until 2021 November.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9   0  3.83   48 10.0   6.947   6.314    47   16.4   5:16 (213, -7)  
May  16   0  9.88   49  5.2   6.869   6.269    50   16.4   5:20 (209, -5)  

* C/2017 U7 ( PanSTARRS )

Now it is 15.8 mag (Apr. 28, ATLAS-MLO, Mauna Loa). It is observable at 16 mag in 2020. It is observable in excellent condition in the Southern Hemisphere. It locates somewhat low in the Northern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9  19 56.88  -29 49.2   6.163   6.621   112   16.6   4:49 (180, 85)  
May  16  19 52.17  -29 48.9   6.062   6.633   120   16.6   4:17 (180, 85)  

* C/2019 C1 ( ATLAS )

Now it is 16.8 mag (Apr. 28, ATLAS-MLO, Mauna Loa). It stays observable at 16-17 mag from 2020 to 2021. It locates somewhat low in the Northern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9  10 41.93  -18 25.0   6.048   6.581   117   16.6  19:32 (180, 73)  
May  16  10 43.19  -17 48.7   6.135   6.582   112   16.6  19:05 (180, 73)  

* C/2016 M1 ( PanSTARRS )

It brightened up to 7.7 mag in June in 2018 (June 19, Juan Jose Gonzalez). Now it is fading. It has already faded down to 16.9 mag (Apr. 22, J. Drummond). In the Southern Hemisphere, it stays observable for a long time until the comet will fade out, although it becomes extremely low in June. In the Northern Hemisphere, it is not observable until late August.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9   5 46.99  -13 17.4   7.232   6.635    50   16.7  18:36 ( 96, 32)  
May  16   5 50.28  -12 40.9   7.344   6.689    46   16.8  18:32 ( 94, 28)  

* C/2017 M4 ( ATLAS )

It brightened up to 12-13 mag from 2018 to 2019. Now it is fading. It has already faded down to 16.9 mag (Apr. 25, Blue Mountains Observatory, Leura). In the Southern Hemisphere, it stays observable in good condition for a long time. It will never be observable after this in the Northern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9   9 20.16  -67 47.4   5.005   5.395   107   16.8  18:36 (  5, 57)  
May  16   9 16.06  -66 13.3   5.078   5.442   105   16.9  18:32 ( 10, 58)  

* P/2019 Y2 ( Fuls )

Now it is 16.8 mag (Apr. 21, ATLAS-MLO, Mauna Loa). It will be fading after this, and it will be fainter than 18 mag in late June.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9  13  0.97    0 30.9   1.339   2.240   144   16.9  21:50 (180, 55)  
May  16  12 59.98    0  8.1   1.401   2.257   138   17.1  21:22 (180, 55)  

* P/2020 G1 ( Pimentel )

New comet. Now it is 15.3 mag (Apr. 25, Ken-ichi Kadota). It approached to Sun down to 0.5 a.u. in March, and it must have brightened up to 14 mag. It will fade out very rapidly after this.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9   8 21.77   -3 29.7   0.737   1.152    80   17.0  18:36 (144, 53)  
May  16   9  7.31   -4 31.9   0.823   1.255    85   17.6  18:32 (152, 57)  

* C/2017 Y2 ( PanSTARRS )

Now it is 17.1 mag (Apr. 23, D. Buczynski). It will be observable at 16.5-17 mag from spring in 2020 to summer in 2021.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9  19 46.31   23 34.4   4.570   4.848    99   17.0   4:38 (180, 31)  
May  16  19 40.30   23 51.8   4.458   4.832   105   17.0   4:05 (180, 31)  

* C/2019 T4 ( ATLAS )

Now it is 16.9 mag (Apr. 24, J. Drummond). It is expected to brighten up to 13 mag in 2022. In 2020, it is observable in excellent condition in the Southern Hemisphere. In the Northern Hemisphere, it is not observable. It will be observable from autumn to winter, but it locating extremely low.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9   6 28.52  -27  3.9   7.662   7.318    66   17.0  18:36 ( 87, 47)  
May  16   6 32.73  -26 38.7   7.675   7.278    63   17.0  18:32 ( 85, 43)  

* 124P/Mrkos

It brightened up to 15.9 mag in February and March (Feb. 18, Toshihiko Ikemura, Hirohisa Sato). Now it is fading. It has already faded down to 17.3 mag (Apr. 26, A. Diepvens). It will be fainter than 18 mag in late June.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9  10  7.80    2 21.1   1.080   1.652   104   17.1  18:58 (180, 53)  
May  16  10 13.98   -0 55.4   1.146   1.657   100   17.2  18:37 (180, 56)  

* 87P/Bus

Now it is 16.4 mag (Apr. 14, Katsumi Yoshimoto). It will fade out after this, and will be fainter than 18 mag in late June.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9  12 35.06   -1 44.5   1.223   2.100   140   17.2  21:25 (180, 57)  
May  16  12 36.00   -1 43.4   1.271   2.100   133   17.2  20:58 (180, 57)  

* C/2020 F2 ( ATLAS )

Now it is 17.9 mag (Apr. 25, Ken-ichi Kadota). It stays observable at 16-17 mag for a long time until 2024.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9  16  5.81  -17 56.0   8.958   9.938   165   17.2   0:59 (180, 73)  
May  16  16  1.52  -17 37.8   8.916   9.919   172   17.2   0:27 (180, 73)  

* C/2018 W2 ( Africano )

It brightened up to 8.3 mag in last September (Sept. 20, Maik Meyer). Now it is fading. It has already faded down to 17.1 mag (Apr. 5, iTelescope Observatory, Siding Spring). In the Southern Hemisphere, it stays observable for a long time after this. In the Northern Hemisphere, it will never be observable again.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9   1 18.39  -62 30.9   3.435   3.452    82   17.4   5:16 (326, 38)  
May  16   1 34.48  -64 24.8   3.435   3.522    86   17.5   5:20 (328, 40)  

* 28P/Neujmin 1

Now it is 17.2 mag (Apr. 24, J. Drummond). It will brighten up to 15.5 mag in early 2021. In 2020, it stays observable at 17 mag until November in the Southern Hemisphere, or until July in the Northern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9  14 31.76  -33 16.3   2.585   3.561   162   17.4  23:20 (180, 88)  
May  16  14 25.05  -32 58.5   2.542   3.507   159   17.4  22:46 (180, 88)  

* C/2010 U3 ( Boattini )

Now it is 17.6 mag (Apr. 27, ATLAS-MLO, Mauna Loa). It will be fading slowly after this. It is observable in good condition in the Northern Hemisphere. In the Southern Hemisphere, it is observable in the extremely low sky only in 2021 spring.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9  12 44.58   54  2.5   8.554   8.830   102   17.5  21:34 (180,  1)  
May  16  12 42.03   53 24.5   8.630   8.842    98   17.5  21:04 (180,  2)  

* 257P/Catalina

Now it is 17.6 mag (Apr. 24, D. Buczynski). It will brighten up to 16.5 mag and will be observable in good condition from June to October.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9  20 13.58    4 24.0   1.933   2.341   100   17.6   5:05 (180, 51)  
May  16  20 19.80    6  3.8   1.846   2.321   104   17.5   4:44 (180, 49)  

* 278P/McNaught

Now it is 17.3 mag (Apr. 24, Catalina Sky Survey). It became brighter than orignally predicted. It stays observable at 17 mag in good condition until autumn.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9  12 41.43   -6 54.2   1.410   2.301   143   17.6  21:31 (180, 62)  
May  16  12 39.14   -7  2.1   1.439   2.280   136   17.5  21:01 (180, 62)  

* C/2019 T3 ( ATLAS )

Now it is 17.3 mag (Apr. 23, D. Buczynski). It will be observable at 16.5-17 mag from 2020 to 2021.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9   1 49.15   67  5.7   6.885   6.302    51   17.6   5:16 (206,-29)  
May  16   1 53.11   67 18.6   6.877   6.286    50   17.6   5:20 (204,-26)  

* C/2014 F3 ( Sheppard-Trujillo )

It will pass the perihelion in 2021, and it is predicted to be observable at 17-18 mag from 2020 to 2022. However, it has not been observed at all since 2015. It was not detected, fainter than 20.5 mag, in 2017 May (Werner Hasubick).

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9  20 38.88  -21 60.0   5.782   6.074   102   17.6   5:16 (196, 76)  
May  16  20 40.21  -21 55.3   5.663   6.061   108   17.6   5:05 (180, 77)  

* C/2017 K5 ( PanSTARRS )

Now it is 18.4 mag (Apr. 22, W. Hasubick). It stays observable at 18 mag for a long time from 2019 to 2021.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9  19 15.83  -16 44.0   7.127   7.684   120   17.7   4:08 (180, 72)  
May  16  19 14.12  -17 12.6   7.030   7.686   127   17.7   3:39 (180, 72)  

* 117P/Helin-Roman-Alu 1

Now it is 17.7 mag (Apr. 14, Y. Sugiyama). It will brighten up to 13 mag in 2022. In 2020, it is observable at 17.5 mag in good condition in spring. It locates somewhat low in the Southern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9  10  9.62   21  3.4   4.151   4.410    98   17.7  19:00 (180, 34)  
May  16  10 11.24   20 38.9   4.243   4.397    92   17.7  18:34 (180, 34)  

* 17P/Holmes

It brightens up to 13.5 mag in winter. But it is not observable at high light. In the Southern Hemisphere, it stays observable in good condition until autumn when the comet will brighten up to 14 mag. It stays locating very low in the Northern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9  19  1.24  -45  9.0   2.235   2.919   123   18.0   3:54 (  0, 80)  
May  16  19  1.41  -45 39.1   2.138   2.889   129   17.8   3:27 (  0, 79)  

* (944) Hidalgo

Now it is 17.6 mag (Feb. 3, ATLAS-HKO, Haleakala). It brightened up to 14 mag from autumn to winter in 2018. Now it is fading. It will be fainter than 18 mag in May.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May   9  12 49.59   -3  5.7   4.038   4.891   144   17.8  21:39 (180, 58)  
May  16  12 46.03   -3 12.5   4.146   4.929   136   17.9  21:08 (180, 58)  

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