Weekly Information about Bright Comets (2026 Sept. 19: South)

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Updated on September 22, 2026
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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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* 10P/Tempel 2

Now it is 8.9 mag (Sept. 17, Yoshimi Nagai). It will fade out rapidly after this. It locates somewhat low in the Northern Hemisphere. But it will become high in autumn. In the Southern Hemisphere, it stays observable in good condition.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19  22 36.05  -35  3.2   0.574   1.504   143    9.2  22:44 (180, 90)  
Sept.26  22 42.51  -34 23.8   0.623   1.530   139    9.5  22:23 (180, 89)  

* 169P/NEAT

It approached to Earth down to 0.17 a.u. mid August. Now it is 11.0 mag (Sept. 9, Mike Olason). It will fade out rapidly after this. It will be fainter than 18 mag in November. It locates somewhat low in the Northern Hemisphere. It stays extremely low in the Southern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19   9 33.70    8  3.9   0.585   0.606    33   10.3   4:30 (257,  5)  
Sept.26   9 43.42    5 43.9   0.711   0.611    37   10.8   4:19 (258,  8)  

* 161P/Hartley-IRAS

Now it is 11.5 mag (Sept. 9, Michael Jager). Brightening slowly. In the Northern Hemisphere, it stays observable in good condition. In the Southern Hemisphere, it will be getting lower gradually after this, and it will be unobservable in November.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19   1 26.37  -14 53.4   0.620   1.578   151   11.6   1:39 (180, 70)  
Sept.26   0 21.79  -10 50.5   0.530   1.525   167   10.9   0:09 (180, 66)  

* 220P/McNaught

Major outburst of about 9 mag occured from May 31 to June 1, and it brightened up to 8.3 mag (June 3, Marco Goiato). Another major outburst occued on Aug. 5 and it brightened up to 6.4 mag (Aug. 6, Taras Prystavski). Now it is 11.6 mag (Sept. 21, Osamu Miyazaki). Fading rapidly. It will be fainter than 18 mag in November. It stays observable in good condition.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19   3 31.57    7 21.1   1.058   1.809   122   11.6   3:42 (180, 48)  
Sept.26   3 33.08    6 32.6   1.039   1.842   128   12.2   3:16 (180, 48)  

* C/2024 T5 ( ATLAS )

Now it is 12.9 mag (Sept. 3, Jean-Gabriel Bosch). It stays 13 mag for a while. It stays observable in good condition.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19   5 41.04  -13 12.7   4.188   4.327    91   13.0   4:30 (225, 62)  
Sept.26   5 43.45  -13 20.4   4.076   4.299    96   12.9   4:19 (219, 64)  

* 260P/McNaught

Now it is 13.4 mag (Sept. 8, M. Jaeger, G. Rhemann, E. Prosperi). It will fade out rapidly after this. In the Northern Hemisphere, it stays observable in good condition. It stays extremely low in the Southern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19   5 18.22   39 45.3   1.053   1.504    93   13.2   4:30 (192, 14)  
Sept.26   5 34.46   41 35.8   1.039   1.532    97   13.3   4:19 (191, 12)  

* 88P/Howell

It brightened up to 9.6 mag in the very low sky in spring (Apr. 14, Chris Wyatt). Now it is 14.1 mag (Sept. 13, Ken-ichi Kadota). It will fade out rapidly after this. It stays observable in good condition.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19   3 15.64   15  1.0   1.541   2.273   125   13.3   3:26 (180, 40)  
Sept.26   3 12.40   14 54.0   1.518   2.319   132   13.4   2:55 (180, 40)  

* 78P/Gehrels 2

Now it is 13.6 mag (Sept. 8, M. Jaeger, G. Rhemann, E. Prosperi). It stays 14 mag for a while. In the Northern Hemisphere, it stays observable in good condition.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19   7  1.00   18 16.2   2.222   2.124    71   13.3   4:30 (222, 24)  
Sept.26   7 12.88   17 36.2   2.167   2.143    75   13.3   4:19 (222, 26)  

* C/2024 J3 ( ATLAS )

Now it is 14.0 mag (Sept. 17, Yoshimi Nagai). It stays 14 mag for a while. In the Northern Hemisphere, it stays observable in good condition. In the Southern Hemisphere, it will be unobservable in October.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19  18 27.97   42 39.0   3.661   3.910    96   13.6  19:18 (172, 12)  
Sept.26  18 26.28   42 17.4   3.704   3.901    93   13.6  19:23 (165, 11)  

* C/2026 A2 ( Bok )

Now it is 14.3 mag (Sept. 17, Kunihiro Shima). Brightening slowly. In the Northern Hemisphere, it stays observable in good condition. In the Southern Hemisphere, it is not observable now, but it will appear in November.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19  17 16.58   71 51.0   2.083   2.253    86   14.2  19:18 (171,-19)  
Sept.26  17 41.55   70 12.0   1.996   2.211    88   14.0  19:23 (170,-17)  

* 29P/Schwassmann-Wachmann 1

Now it is 13.6 mag (Aug. 2, Andrew Pearce). Now it is not observable. It will appear in October in the Northern Hemisphere, or in November in the Southern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19  11 56.06   -6 21.9   7.310   6.318     8   14.3  19:18 ( 74,-11)  
Sept.26  12  0.82   -6 55.1   7.314   6.318     6   14.3   4:19 (288,-13)  

* C/2014 UN271 ( Bernardinelli-Bernstein )

Very large comet. Now it is 13.9 mag (Aug. 16, Thomas Lehmann). It stays 14 mag for a while. In the Northern Hemisphere, it is not observable now. In the Southern Hemisphere, it stays observable in good condition. In the Northern Hemisphere, it is not observable until 2030.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19   7 27.77  -70 58.7  13.685  13.607    83   14.5   4:30 (340, 47)  
Sept.26   7 32.13  -71 24.6  13.680  13.587    82   14.5   4:19 (341, 47)  

* 252P/LINEAR

It has not been observed yet in this apparition. It has brightened up to 4 mag in 2016, and 10 mag in 2021. Brightening rapidly. It stays extremely low in the Northern Hemisphere. In the Southern Hemisphere, it will be unobservable in October. But it will be observable again in January.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19   9 40.50    7 26.4   1.952   1.212    31   15.2   4:30 (258,  4)  
Sept.26  10  8.06    5 19.9   1.903   1.163    30   14.5   4:19 (261,  3)  

* C/2024 R4 ( PanSTARRS )

Now it is 14.4 mag (Sept. 5, Alfons Diepvens). It stays 14 mag for a while. In the Northern Hemisphere, it stays observable in good condition. In the Southern Hemisphere, it will be unobservable in November.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19  20 11.28   48 29.3   5.014   5.470   111   14.6  20:18 (180,  6)  
Sept.26  20  3.64   47 50.7   5.020   5.438   109   14.6  19:42 (180,  7)  

* C/2023 R1 ( PanSTARRS )

Now it is 14.7 mag (Sept. 7, Andrew Pearce). It stays 15 mag for a while. It will be unobservable in October in the Northern Hemisphere, or in November in the Southern Hemisphere. But it will be observable again in December.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19  15 27.46  -16 40.2   4.285   3.848    58   14.6  19:18 ( 95, 37)  
Sept.26  15 27.17  -17 16.5   4.420   3.872    51   14.7  19:23 ( 90, 31)  

* 123P/West-Hartley

It stays 15 mag for a while. It locates somewhat low in the Northern Hemisphere. But it will become high in winter. In the Southern Hemisphere, it is not observable now, but it will appear in November.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19  10 53.68   18 19.8   3.069   2.159    20   15.0   4:30 (259,-17)  
Sept.26  11  8.77   16 46.0   3.044   2.159    23   14.9   4:19 (260,-16)  

* 63P/Wild 1

It brightened up to 13.0 mag in early summer (July 3, Thomas Lehmann). It will fade out rapidly after this. It will be fainter than 18 mag in December. Now it is not observable. It will appear in December.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19  12 32.12   -8 44.8   3.055   2.106    15   15.1  19:18 ( 77, -2)  
Sept.26  12 46.21  -10 52.4   3.093   2.131    13   15.3  19:23 ( 73, -5)  

* 112P/Urata-Niijima

Now it is 16.8 mag (Sept. 19, Francois Kugel). Fading slowly. In the Northern Hemisphere, it stays observable in good condition. In the Southern Hemisphere, it will be unobservable in November.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19   6 18.16   32 59.0   1.184   1.442    81   15.7   4:30 (206, 17)  
Sept.26   6 42.99   35 25.7   1.151   1.442    83   15.5   4:19 (206, 14)  

* C/2022 QE78 ( ATLAS )

Now it is 15.5 mag (June 14, Alfons Diepvens). It stays 16 mag for a while. In the Northern Hemisphere, it will be getting higher gradually. In the Southern Hemisphere, it is not observable now, but it will appear in November.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19  11  0.27   26 50.0   6.986   6.110    27   15.6   4:30 (252,-23)  
Sept.26  11  6.55   26 38.5   6.965   6.132    31   15.6   4:19 (251,-21)  

* C/2025 Y1 ( ATLAS )

Now it is 16.1 mag (Aug. 5, Ken-ichi Kadota). Brightening slowly. It will be unobservable soon. But it will be observable again in November in the Northern Hemisphere, or in December in the Southern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19  13 29.66   -0 50.5   5.555   4.677    26   15.9  19:18 ( 92,  5)  
Sept.26  13 36.04   -1 25.6   5.541   4.624    21   15.9  19:23 ( 88, -1)  

* C/2022 N2 ( PanSTARRS )

Now it is 15.9 mag (Sept. 1, ATLAS-HKO, Haleakala). It stays 16 mag for a while. In the Northern Hemisphere, it stays observable in good condition. It locates somewhat low in the Southern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19   7 18.43   25 46.2   5.501   5.211    68   15.9   4:30 (221, 16)  
Sept.26   7 22.71   25 39.5   5.437   5.249    73   15.9   4:19 (219, 18)  

* C/2025 M2 ( PanSTARRS )

It is expected to brighten up to 12 mag from 2027 to 2028. Now it is 15.9 mag (Aug. 28, Jean-Claude Merlin). It stays 16 mag for a while. It will be getting lower gradually after this, and it will be unobservable in December.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19  18 53.91  -21 20.0   4.609   4.993   106   16.0  19:18 (164, 76)  
Sept.26  18 49.15  -21 23.6   4.686   4.941    98   16.0  19:23 (135, 72)  

* C/2021 G2 ( ATLAS )

Now it is 15.8 mag (Aug. 25, Toru Yusa). It stays 17 mag for a while. In the Northern Hemisphere, it will be getting lower gradually. But it will be getting higher again after December. In the Southern Hemisphere, it will be getting lower gradually after this, and it will be unobservable in November.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19  17  3.49   13 27.4   7.515   7.402    79   16.1  19:18 (143, 33)  
Sept.26  17  5.79   13  7.9   7.638   7.437    74   16.2  19:23 (135, 29)  

* 114P/Wiseman-Skiff

Now it is 16.8 mag (Sept. 20, Catalina Sky Survey). Fading slowly. In the Northern Hemisphere, it stays observable in good condition. It locates somewhat low in the Southern Hemisphere. But it will become high in autumn.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19   8  5.40   21 34.0   1.878   1.571    56   16.3   4:30 (232, 12)  
Sept.26   8 24.32   19 23.6   1.840   1.575    58   16.3   4:19 (234, 13)  

* C/2025 R3 ( PanSTARRS )

It brightened up to 4.0 mag in late April (Apr. 30, Chris Wyatt). It brightened up to 1.3 mag due to the forward scattering in the SOHO LASCO images (Apr. 25, Mikolaj Kaszczyk). It faded down to 13.4 mag until summer (Aug. 15, Thomas Lehmann). Fading gradually. It will be fainter than 18 mag in November. It locates somewhat low in the Northern Hemisphere. In the Southern Hemisphere, it stays observable in good condition.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19   7 36.63  -23 19.5   2.990   2.724    65   16.5   4:30 (268, 46)  
Sept.26   7 34.57  -24 45.4   2.992   2.817    70   16.7   4:19 (267, 51)  

* 84P/Giclas

Now it is 16.7 mag (Sept. 9, Andrew Pearce). It stays 16 mag for a while. It locates somewhat low in the Northern Hemisphere. In the Southern Hemisphere, it stays observable in good condition.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19  20 15.26  -26 27.9   1.439   2.169   124   16.6  20:23 (180, 81)  
Sept.26  20 16.71  -26 30.3   1.475   2.134   117   16.6  19:57 (180, 81)  

* C/2025 J1 ( Borisov )

Now it is 17.9 mag (Sept. 17, Kunihiro Shima). It stays 17 mag for a while. In the Northern Hemisphere, it stays observable in good condition. In the Southern Hemisphere, it will be getting higher gradually.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19   7 14.76   16  7.9   3.952   3.691    67   16.7   4:30 (227, 24)  
Sept.26   7 15.66   14 36.8   3.852   3.707    74   16.6   4:19 (224, 28)  

* 65P/Gunn

Now it is 17.7 mag (Sept. 10, Andrew Pearce). Fading slowly. It stays observable in good condition.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19   0 37.53   -7 48.4   2.621   3.603   165   16.7   0:48 (180, 63)  
Sept.26   0 32.81   -8 12.5   2.629   3.618   169   16.7   0:16 (180, 63)  

* C/2026 AZ17 ( Bok )

Now it is 16.7 mag (Sept. 5, Alfons Diepvens). It stays 17 mag for a while. It will be getting lower gradually after this, and it will be unobservable in January in the Northern Hemisphere, or in December in the Southern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19  17  4.75    6 49.6   2.546   2.569    79   16.7  19:18 (139, 39)  
Sept.26  17 14.50    4 52.5   2.592   2.550    76   16.7  19:23 (131, 37)  

* 2P/Encke

It will brighten up to 6-7 mag from January to February. Now it is 17.0 mag (Sept. 20, Alfons Diepvens). It will brighten rapidly after this. In the Northern Hemisphere, it stays observable in good condition. In the Southern Hemisphere, it will be getting lower gradually after this, and it will be unobservable in January.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19   1 11.66   20 29.2   1.347   2.269   149   17.4   1:23 (180, 34)  
Sept.26   1  0.30   20 21.7   1.243   2.201   156   17.0   0:44 (180, 34)  

* C/2025 E1 ( PanSTARRS )

Now it is 17.6 mag (Sept. 12, ATLAS Chile). It stays 17 mag for a while. In the Northern Hemisphere, it will never be observable after this. In the Southern Hemisphere, it stays observable in good condition.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19  11 14.57  -73 39.7   4.130   3.998    75   17.1   4:30 (342, 30)  
Sept.26  11 38.86  -75 11.6   4.151   3.998    74   17.1   4:19 (344, 30)  

* 493P/2024 Q2 ( LONEOS )

Now it is 17.6 mag (May 18, Kunihiro Shima). It stays 17 mag for a while. In the Northern Hemisphere, it will be getting higher gradually. In the Southern Hemisphere, it is not observable now, but it will appear in November.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19   9 31.47   33 12.6   4.755   4.096    44   17.1   4:30 (236,-10)  
Sept.26   9 39.67   32 40.9   4.702   4.111    48   17.1   4:19 (236, -8)  

* C/2024 G6 ( ATLAS )

Now it is 17.3 mag (Sept. 1, ATLAS-HKO, Haleakala). It stays 17 mag for a while. It locates somewhat low in the Northern Hemisphere. But it will become high in winter. In the Southern Hemisphere, it will be unobservable in October. But it will be observable again in January.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19  15  8.58   15 12.0   7.155   6.586    52   17.1  19:18 (120, 14)  
Sept.26  15 10.22   15  8.8   7.232   6.596    47   17.2  19:23 (115,  8)  

* C/2022 E2 ( ATLAS )

It was observed at 12-13 mag for a long time in 2024. Now it is 17.3 mag (Sept. 5, Toru Yusa). Fading slowly. It will be fainter than 18 mag in November. In the Northern Hemisphere, it stays observable in good condition. It locates somewhat low in the Southern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19  22  4.62   27  9.2   6.290   7.113   142   17.3  22:11 (180, 28)  
Sept.26  21 59.86   26 10.5   6.361   7.158   139   17.4  21:39 (180, 29)  

* P/2018 VN2 = P/2026 M2 ( Leonard )

First return of a new periodic comet which was observed at 18 mag in 2018. Now it is 17.2 mag (Sept. 5, ATLAS-MLO, Mauna Loa). Fading slowly. It will be fainter than 18 mag in December. In the Northern Hemisphere, it stays observable in good condition.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19   2  5.44   27 28.8   1.304   2.138   135   17.4   2:16 (180, 27)  
Sept.26   2  5.49   26 37.7   1.264   2.146   142   17.3   1:48 (180, 28)  

* C/2024 G4 ( PanSTARRS )

Now it is 17.6 mag (Sept. 16, ATLAS Chile). It stays 18 mag for a while. It stays observable in good condition.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19  20  0.54   -4 27.6   4.467   5.098   124   17.3  20:08 (180, 59)  
Sept.26  20  1.42   -5 13.0   4.568   5.113   117   17.4  19:41 (180, 60)  

* C/2019 E3 ( ATLAS )

Very far object. It stays 18 mag for a while. It stays extremely low in the Northern Hemisphere. In the Southern Hemisphere, it stays observable in good condition.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19   0 14.77  -45 23.8  10.944  11.686   135   17.4   0:26 (  0, 80)  
Sept.26   0 10.94  -45 21.9  10.988  11.703   133   17.4  23:50 (  0, 80)  

* 93P/Lovas 1

It stays 18 mag for a while. In the Northern Hemisphere, it will be getting higher gradually. In the Southern Hemisphere, it is not observable now, but it will appear in October.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19   9 28.85   20 57.2   2.882   2.183    38   17.4   4:30 (246, -2)  
Sept.26   9 41.77   19 44.3   2.871   2.224    41   17.5   4:19 (246,  0)  

* 11P/Tempel-Swift-LINEAR

Now it is 17.5 mag (Sept. 20, Alfons Diepvens). It will brighten rapidly after this. In the Northern Hemisphere, it stays observable in good condition. It locates somewhat low in the Southern Hemisphere. But it will become high in autumn.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19   1 37.73   38 58.3   0.631   1.500   131   17.8   1:48 (180, 16)  
Sept.26   1 48.44   39 33.5   0.580   1.473   135   17.5   1:31 (180, 15)  

* 188P/LINEAR-Mueller

Now it is 17.9 mag (Aug. 24, W. Hasubick). It stays 18 mag for a while. In the Northern Hemisphere, it stays observable in good condition. It stays extremely low in the Southern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19   6  1.31   33 44.5   2.658   2.767    85   17.5   4:30 (202, 17)  
Sept.26   6  8.94   34 11.7   2.587   2.786    90   17.5   4:19 (200, 18)  

* 235P/LINEAR

It became brighter than expected. It was observed at 13 mag from winter to spring. Now it is 17.2 mag (Aug. 30, ATLAS South Africa). Fading gradually. It will be fainter than 18 mag in October. It locates somewhat low in the Northern Hemisphere. In the Southern Hemisphere, it will be getting lower gradually.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19  17 17.55  -13  5.3   2.713   2.791    83   17.6  19:18 (124, 57)  
Sept.26  17 25.76  -13 30.3   2.832   2.821    79   17.8  19:23 (116, 52)  

* P/2021 N1 = P/2026 M1 ( ZTF )

First return of a new periodic comet which brightened up to 17 mag in 2021. It approached to Earth down to 0.17 a.u. from June to July. It brightened up to 15.2 mag (July 14, Andrew Pearce). Now it is 17.4 mag (Sept. 7, Toru Yusa). It will fade out rapidly after this. It will be fainter than 18 mag in October. In the Northern Hemisphere, it stays observable in good condition. It stays extremely low in the Southern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19   5  3.67   46 57.3   0.586   1.212    95   17.6   4:30 (188,  7)  
Sept.26   5  6.21   47 37.4   0.605   1.269   101   17.9   4:19 (185,  7)  

* C/2025 B2 ( Borisov )

Now it is 17.3 mag (Sept. 4, ATLAS-MLO, Mauna Loa). It stays 18 mag for a while. In the Northern Hemisphere, it stays observable in good condition. In the Southern Hemisphere, it will never be observable after this.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19  16 42.87   76 53.4   8.267   8.239    84   17.6  19:18 (171,-24)  
Sept.26  16 48.61   75 42.5   8.246   8.239    86   17.6  19:23 (169,-24)  

* C/2023 X2 ( Lemmon )

Now it is 17.8 mag (July 6, ATLAS-MLO, Mauna Loa). It stays 18 mag for a while. In the Northern Hemisphere, it will be getting lower gradually. But it will be getting higher again after November. In the Southern Hemisphere, it will never be observable after this.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19  14 43.65   57 50.1   5.795   5.469    66   17.7  19:18 (149,-18)  
Sept.26  14 51.55   56 20.8   5.819   5.488    66   17.7  19:23 (145,-20)  

* 346P/Catalina

It stays 18 mag for a while. In the Northern Hemisphere, it stays observable in good condition. It locates somewhat low in the Southern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19   8  1.40   18 26.9   2.634   2.252    57   18.0   4:30 (234, 15)  
Sept.26   8 14.69   18 33.0   2.575   2.263    60   17.9   4:19 (233, 16)  

* C/2026 P2 ( PanSTARRS )

It is expected to brighten up to 13.5 mag from late 2027 to early 2028. At the high light, it will be observable in good condition in the Northern Hemisphere. But it will not be observable in the Southern Hemisphere. Now it is 17.4 mag (Aug. 24, Hidenori Nohara). It stays 18 mag for a while. It stays observable in good condition.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Sept.19   1 46.28   -2  2.2   4.072   4.964   149   18.0   1:57 (180, 57)  
Sept.26   1 41.19   -1 58.3   3.972   4.910   156   17.9   1:24 (180, 57)  

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