Weekly Information about Bright Comets (2025 May 17: South)

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Updated on May 27, 2025
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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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* 21P/Giacobini-Zinner

It brightened up to 11 mag in the SWAN images (Jan. 27, Vladimir Bezugly). It will fade out rapidly after this. Now it is not observable. It will appear in July in the Southern Hemisphere, or in September in the Northern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May  17   3 57.82    6 46.8   2.210   1.250    13   12.6  18:31 ( 94, -6)  
May  24   4 22.78    6 35.4   2.259   1.307    14   13.0  18:28 ( 94, -6)  

* C/2025 F2 ( SWAN )

Bright new comet discovered in the SWAN images. It brightened rapidly up to 7.8 mag on Apr. 8 (Osamu Miyazaki). The nucleus was disintegrated, however, its remnant is still visible. Fading rapidly. It will be fainter than 18 mag in August. In the Northern Hemisphere, it will never be observable after this. It locates somewhat low in the Southern Hemisphere. But it will become high in summer.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May  17   5  4.40   -0  6.4   1.137   0.556    29   12.6  18:31 ( 97, 11)  
May  24   5 17.79   -8 12.5   1.248   0.703    34   13.4  18:28 ( 89, 14)  

* C/2023 A3 ( Tsuchinshan-ATLAS )

It brightened up to -3 mag due to the forward scattering on Oct. 9 in the SOHO coronagraph images (Q.-c. Zhang, Charles S. Morris). It became a great comet of 0 mag on the ground. Now it is 12.6 mag (Apr. 26, Hiroshi Abe). 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 spring.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May  17  20  0.35   26 23.2   3.467   3.793   101   13.0   4:22 (180, 29)  
May  24  19 52.48   27 16.8   3.463   3.875   106   13.1   3:47 (180, 28)  

* 217P/LINEAR

It is visible at 12-13 mag in the SWAN images (May 2, Vladimir Bezugly). Fading gradually. In the Northern Hemisphere, it is not observable now, but it will appear in July. It stays extremely 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)  
May  17   1 52.56    4 21.3   2.013   1.231    29   13.3   5:21 (257, 11)  
May  24   2 18.62    6 17.2   2.009   1.226    29   13.2   5:25 (254, 11)  

* C/2024 G3 ( ATLAS )

It approached to Sun down to 0.09 a.u. on Jan. 13. It brightened up to -2 or -3 mag and it was detected even in the daylight. The nucleus was disintegrated on Jan. 19. However, its remnant is still visible. Fading gradually. 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)  
May  17   2 14.33  -50 40.7   2.767   2.639    72   13.4   5:21 (312, 33)  
May  24   2 26.23  -52 15.3   2.805   2.741    75   13.6   5:25 (313, 36)  

* 29P/Schwassmann-Wachmann 1

Now it is 12.7 mag (May 20, Osamu Miyazaki). It will be getting lower gradually after this, and it will be unobservable in July in the Northern Hemisphere, or in August in the Southern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May  17   9 39.08   10 32.4   6.239   6.277    87   14.0  18:31 (169, 44)  
May  24   9 41.04   10 22.0   6.351   6.278    81   14.0  18:28 (161, 43)  

* C/2021 G2 ( ATLAS )

Now it is 13.4 mag (May 20, Osamu Miyazaki). It stays 15 mag for a while. It stays observable in good condition.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May  17  15 17.32   -5 42.1   4.351   5.338   165   14.0  23:36 (180, 61)  
May  24  15 14.51   -4 51.7   4.393   5.357   160   14.0  23:05 (180, 60)  

* C/2022 N2 ( PanSTARRS )

Now it is 14.9 mag (Feb. 4, Alfons Diepvens). It stays 14 mag for a while. It locates somewhat low. But it will become high in summer in the Northern Hemisphere, or in winter in the Southern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May  17   1 38.43   14 28.3   4.745   3.883    28   14.3   5:21 (246,  7)  
May  24   1 47.23   15 22.8   4.688   3.873    32   14.2   5:25 (242, 11)  

* 48P/Johnson

Now it is 15.2 mag (May 10, Taras Prystavski). Fading slowly. In the Northern Hemisphere, it is not observable now, but it will appear in June.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May  17   1  9.93   -1 49.2   2.742   2.092    41   14.4   5:21 (255, 23)  
May  24   1 24.11   -0 43.2   2.711   2.108    44   14.5   5:25 (251, 26)  

* 49P/Arend-Rigaux

Now it is 14.5 mag (Apr. 21, Hiroshi Abe). It will fade out rapidly after this. It will be fainter than 18 mag in September. It will be unobservable in July.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May  17   6 14.17   23  6.4   2.160   1.487    37   14.6  18:31 (127,  9)  
May  24   6 38.26   23 53.9   2.206   1.509    36   14.8  18:28 (128,  9)  

* C/2022 E2 ( ATLAS )

It was observed at 12-13 mag for a long time in 2024. Now it is 14.6 mag (Apr. 29, Ken-ichi Kadota). It stays 15 mag for a while. In the Northern Hemisphere, it will be getting higher gradually. In the Southern Hemisphere, it is not observable now.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May  17   1 50.15   49 12.3   5.030   4.261    36   14.6   5:21 (220,-16)  
May  24   1 51.71   49 41.0   5.033   4.292    38   14.7   5:25 (217,-13)  

* C/2022 QE78 ( ATLAS )

Now it is 14.6 mag (May 10, Alfons Diepvens). It stays 15 mag for a while. It will be unobservable in June. But it will be observable again in August.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May  17   6 51.64   16 26.5   6.187   5.544    46   14.9  18:31 (129, 20)  
May  24   6 57.27   16 46.9   6.255   5.536    41   14.9  18:28 (125, 17)  

* C/2014 UN271 ( Bernardinelli-Bernstein )

Very large comet. It is expected to brighten up to 13 mag in 2031. Now it is 14.9 mag (May 3, Thomas Lehmann). It stays 15 mag for a while. In the Northern Hemisphere, it is not observable now. In the Northern Hemisphere, it is not observable until 2030.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May  17   4 19.58  -65 22.9  15.189  15.136    85   15.2  18:31 ( 30, 32)  
May  24   4 24.92  -65 22.9  15.146  15.113    86   15.2  18:28 ( 29, 30)  

* 65P/Gunn

Now it is 15.7 mag (May 7, Thomas Lehmann). It stays 15 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)  
May  17  19  0.88  -28 23.2   2.152   2.930   132   15.3   3:23 (180, 83)  
May  24  19  0.06  -28 53.4   2.086   2.928   139   15.3   2:55 (180, 84)  

* C/2024 J2 ( Wierzchos )

Brightened rapidly. Now it is 14.6 mag (Jan. 31, Thomas Lehmann). Fading slowly. It stays extremely low in the Northern Hemisphere. But it will become high in summer. In the Southern Hemisphere, it will be getting higher gradually.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May  17   1 23.39   12 47.5   2.735   1.954    32   15.3   5:21 (245, 11)  
May  24   1 35.53   11 27.9   2.710   1.988    36   15.4   5:25 (243, 16)  

* 43P/Wolf-Harrington

Now it is 16.5 mag (Apr. 7, Alfons Diepvens). It stays 15 mag for a while. Now it is not observable. It will appear in August.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May  17   4 58.40   20 23.8   3.439   2.510    19   15.4  18:31 (113, -2)  
May  24   5 12.58   20 30.2   3.455   2.499    16   15.4  18:28 (112, -4)  

* C/2023 C2 ( ATLAS )

It brightened up to 12.7 mag in 2024 summer (Aug. 7, 2024, Thomas Lehmann). Now it is 15.5 mag (May 24, Martin Masek). It stays 16 mag for a while. In the Northern Hemisphere, it stays observable in good condition. In the Southern Hemisphere, it will be unobservable in August.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May  17  23 15.19   31 16.8   3.477   3.083    59   15.4   5:21 (210, 16)  
May  24  23 21.23   33 37.0   3.460   3.130    62   15.4   5:25 (204, 17)  

* C/2024 L5 ( ATLAS )

Now it is 15.3 mag (May 13, Ken-ichi Kadota). Fading slowly. It will be getting lower gradually after this, and it will be unobservable in July in the Northern Hemisphere, or in August in the Southern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May  17  11 33.82  -11 48.2   2.852   3.491   121   15.4  19:52 (180, 67)  
May  24  11 24.92   -9 56.4   2.988   3.504   112   15.6  19:16 (180, 65)  

* C/2023 R1 ( PanSTARRS )

It is expected to brighten up to 13 mag in early summer in 2026. Now it is 16.0 mag (May 13, ATLAS-MLO, Mauna Loa). Brightening 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)  
May  17  22 33.60   22 16.5   4.882   4.629    69   15.6   5:21 (205, 28)  
May  24  22 31.38   22 51.9   4.733   4.591    75   15.5   5:25 (196, 30)  

* C/2024 E1 ( Wierzchos )

It is expected to brighten up to 5 mag in 2026 January. Now it is 16.0 mag (May 8, Ken-ichi Kadota). Brightening gradually. In the Northern Hemisphere, it stays observable in good condition. In the Southern Hemisphere, it is not observable now, but it will appear in July.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May  17  18  7.09   56 32.2   3.598   3.866    97   15.7   2:29 (180, -2)  
May  24  17 57.89   57 19.7   3.504   3.786    98   15.5   1:52 (180, -2)  

* C/2024 J3 ( ATLAS )

It will brighten up to 13 mag in 2026. Now it is 15.9 mag (Apr. 29, Ken-ichi Kadota). It stays 15 mag for a while. It stays observable in good condition.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May  17  19 44.17  -20 59.0   5.452   6.046   121   15.7   4:06 (180, 76)  
May  24  19 41.57  -20 29.8   5.315   6.005   129   15.6   3:36 (180, 75)  

* P/2023 S1 ( PanSTARRS )

It brightened up to 14.4 mag in winter (Feb. 4, Ken-ichi Kadota). Now it is 16.2 mag (May 13, ATLAS South Africa). Fading slowly. It will be getting lower gradually after this, and it will be unobservable in July in the Northern Hemisphere, or in September in the Southern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May  17   9 13.11   12 29.1   2.631   2.665    80   15.6  18:31 (161, 41)  
May  24   9 21.41   11 41.0   2.724   2.673    76   15.7  18:28 (156, 40)  

* C/2023 T3 ( Fuls )

Now it is 15.3 mag (May 4, Toshiyuki Takahashi). Fading slowly. 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)  
May  17  13  6.35  -28 36.2   2.816   3.690   144   15.6  21:25 (180, 84)  
May  24  13  6.79  -27 29.8   2.880   3.708   139   15.7  20:58 (180, 83)  

* C/2023 F3 ( ATLAS )

Now it is 16.2 mag (May 8, Ken-ichi Kadota). It stays 17 mag for a while. It will be unobservable in June in the Northern Hemisphere, or in September in the Southern Hemisphere. But it will be observable again in September in the Southern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May  17  10 48.00  -34  0.9   4.734   5.249   115   16.1  19:07 (180, 89)  
May  24  10 43.70  -32 26.9   4.836   5.257   109   16.1  18:35 (180, 87)  

* 496P/2024 S3 ( Hill )

First return of a new periodic comet which brightened up to 15 mag in 2010. Now it is 16.0 mag (May 11, ATLAS-HKO, Haleakala). It will fade out rapidly after this. It will be fainter than 18 mag in July. In the Northern Hemisphere, it will be getting lower gradually. It stays extremely low in the Southern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May  17   7 59.82   33 31.5   2.073   1.796    60   16.1  18:31 (152, 15)  
May  24   8 21.69   32 21.2   2.149   1.831    58   16.3  18:28 (151, 16)  

* C/2023 H5 ( Lemmon )

Now it is 15.6 mag (May 14, Alfons Diepvens). It stays 16 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)  
May  17  10 36.83   65 43.7   4.412   4.328    78   16.1  18:57 (180,-11)  
May  24  10 35.80   65 33.4   4.482   4.324    74   16.2  18:28 (180,-10)  

* C/2024 A1 ( ATLAS )

Now it is 16.5 mag (May 8, Thomas Lehmann). It stays 17 mag for a while. It will be unobservable in June. But it will be observable again in August in the Northern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May  17   6 48.60   12 51.0   4.503   3.883    46   16.4  18:31 (125, 22)  
May  24   6 53.26   14  0.8   4.585   3.880    41   16.4  18:28 (123, 18)  

* C/2022 R6 ( PanSTARRS )

Now it is 16.2 mag (May 13, ATLAS South Africa). It stays 16 mag for a while. In the Northern Hemisphere, it is not observable now, but it will appear in September. In the Southern Hemisphere, it will be getting lower gradually after this, and it will be unobservable in July. But it will be observable again in July.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May  17   7  6.27  -13 53.4   7.020   6.601    61   16.4  18:31 (105, 43)  
May  24   7 10.81  -13 14.7   7.087   6.596    57   16.4  18:28 (102, 39)  

* 47P/Ashbrook-Jackson

Now it is 17.1 mag (May 7, ATLAS Chile). Brightening slowly. In the Northern Hemisphere, it will be getting higher gradually. In the Southern Hemisphere, it stays observable in good condition.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May  17  22 48.70  -16 31.8   2.983   2.959    78   16.6   5:21 (240, 59)  
May  24  22 55.86  -15 47.9   2.882   2.947    83   16.5   5:25 (230, 63)  

* C/2019 U5 ( PanSTARRS )

Now it is 16.4 mag (May 4, ATLAS South Africa). It stays 17 mag for a while. In the Northern Hemisphere, it is not observable now, but it will appear in September. It locates somewhat low in the Southern Hemisphere. But it will become high in summer.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May  17   5 31.75  -37  4.5   7.806   7.397    62   16.8  18:31 ( 66, 35)  
May  24   5 34.19  -36 44.1   7.874   7.442    61   16.8  18:28 ( 64, 30)  

* 88P/Howell

It will brighten up to 9 mag in 2026 spring. Now it is 17.3 mag (Apr. 30, Andrew Pearce). Brightening slowly. It will be getting lower gradually after this, and it will be unobservable in August in the Northern Hemisphere, or in September in the Southern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May  17  10 19.19   15  9.7   2.761   3.024    95   17.0  18:39 (180, 40)  
May  24  10 21.74   14 43.2   2.822   2.984    89   16.9  18:28 (176, 40)  

* C/2020 V2 ( ZTF )

It was observed at 9-10 mag for a long time in 2023. Now it is 16.6 mag (May 15, ATLAS South Africa). 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)  
May  17  22 18.91  -66 39.2   7.109   7.408   103   17.0   5:21 (346, 56)  
May  24  22 16.70  -67 37.0   7.089   7.460   107   17.0   5:25 (352, 57)  

* C/2019 E3 ( ATLAS )

Very far object. Now it is 16.9 mag (Dec. 20, ATLAS Chile). It stays 17 mag for a while. In the Northern Hemisphere, it is not observable now. In the Southern Hemisphere, it stays observable in good condition.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May  17   1 23.79  -53 12.1  10.888  10.720    77   17.0   5:21 (313, 41)  
May  24   1 25.83  -53 13.8  10.836  10.730    81   17.0   5:25 (313, 46)  

* C/2023 Q1 ( PanSTARRS )

It brightened up to 13.8 mag in winter (Dec. 30, Thomas Lehmann). Now it is 17.2 mag (May 2, Toshihiko Ikemura, Hirohisa Sato). Fading slowly. It will be fainter than 18 mag in July. In the Northern Hemisphere, it will be getting lower gradually. It stays extremely low in the Southern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May  17   9 10.96   41 49.0   3.263   3.120    72   17.0  18:31 (169, 12)  
May  24   9 20.16   39 53.3   3.380   3.161    68   17.1  18:28 (165, 13)  

* C/2021 S3 ( PanSTARRS )

It brightened up to 9.6 mag from February to March in 2024 (Feb. 25, 2024, Thomas Lehmann). Now it is 17.0 mag (May 4, Ken-ichi Kadota). It stays 17 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)  
May  17  23 32.44   38 53.1   6.023   5.511    55   17.1   5:21 (209,  8)  
May  24  23 35.76   39 35.1   6.022   5.575    59   17.1   5:25 (204, 10)  

* C/2019 L3 ( ATLAS )

It brightened up to 8.3 mag in 2021-2022 winter (Jan. 6, 2022, Toshiyuki Takahashi). Now it is 17.7 mag (May 13, Jean-Claude Merlin). It stays 18 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)  
May  17  11 52.08  -57 48.0   9.612  10.216   124   17.1  20:11 (  0, 67)  
May  24  11 51.06  -57 17.8   9.688  10.259   121   17.2  19:43 (  0, 68)  

* C/2024 G2 ( ATLAS )

Now it is 17.3 mag (May 6, ATLAS Chile). It stays 18 mag for a while. It will be unobservable in July in the Northern Hemisphere, or in September in the Southern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May  17  11  7.86  -29 51.6   4.786   5.352   119   17.2  19:27 (180, 85)  
May  24  11  5.80  -28  5.6   4.873   5.350   112   17.2  18:57 (180, 83)  

* 362P/(457175) 2008 GO98

Now it is 17.4 mag (Sept. 20, Taras Prystavski). It stays 17 mag for a while. It stays observable in good condition.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May  17  21 43.65    1 35.5   3.141   3.256    87   17.3   5:21 (198, 52)  
May  24  21 47.58    2 15.0   3.063   3.271    92   17.2   5:25 (187, 52)  

* C/2020 K1 ( PanSTARRS )

It brightened up to 12.1 mag in 2023 spring (May 20, 2023, Jose Guilherme de S. Aguiar). Now it is 17.4 mag (Mar. 25, ATLAS South Africa). It stays 18 mag for a while. In the Northern Hemisphere, it is not observable now, but it will appear in August. It locates somewhat low in the Southern Hemisphere. But it will become high in summer.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May  17   5 52.78  -19 49.0   7.755   7.172    51   17.3  18:31 ( 87, 32)  
May  24   5 56.18  -19 14.4   7.849   7.220    48   17.3  18:28 ( 85, 27)  

* 195P/Hill

Now it is 17.1 mag (May 1, A. Nagy Melykuti). It stays 17 mag for a while. It stays extremely low in the Northern Hemisphere. In the Southern Hemisphere, it will be getting lower gradually after this, and it will be unobservable in July. But it will be observable again in August.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May  17   6 58.74   -5 16.4   4.944   4.456    55   17.3  18:31 (112, 37)  
May  24   7  5.06   -5 17.7   5.009   4.453    51   17.3  18:28 (109, 33)  

* C/2024 T5 ( ATLAS )

Now it is 18.0 mag (Feb. 2, ATLAS Chile). It stays 17 mag for a while. In the Northern Hemisphere, it is not observable now, but it will appear in July. In the Southern Hemisphere, it stays observable in good condition. It is expected to brighten up to 13 mag in winter between 2026 and 2027.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May  17   2 22.81  -37 29.5   7.495   7.032    59   17.3   5:21 (298, 27)  
May  24   2 28.54  -37 19.8   7.404   6.988    62   17.3   5:25 (296, 32)  

* 13P/Olbers

It returned for the first time in 68 years. It brightened up to 6.2 mag in early last summer (July 1, Virgilio Gonano). Now it is 16.3 mag (May 10, ATLAS Chile). It will fade out rapidly after this. It will be fainter than 18 mag in June. 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)  
May  17  18 33.29  -25 59.1   3.293   4.105   138   17.3   2:56 (180, 81)  
May  24  18 27.84  -26 38.3   3.289   4.170   146   17.5   2:23 (180, 82)  

* 302P/Lemmon-PanSTARRS

Now it is 17.3 mag (Oct. 31, ATLAS Chile). It stays 17 mag for a while. In the Northern Hemisphere, it will be getting higher gradually. In the Southern Hemisphere, it stays observable in good condition.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May  17  23 57.66   -4  5.6   3.722   3.303    58   17.4   5:21 (243, 38)  
May  24   0  5.34   -3 26.9   3.642   3.307    62   17.4   5:25 (237, 42)  

* C/2024 X2 ( ATLAS )

Now it is 17.3 mag (May 6, ATLAS Chile). It stays 18 mag for a while. In the Northern Hemisphere, it is not observable now, but it will appear in September. In the Southern Hemisphere, it will be getting lower gradually after this, and it will be unobservable in August. But it will be observable again in August.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May  17   7 39.65  -27 18.7   3.827   3.704    75   17.4  18:31 ( 93, 57)  
May  24   7 44.16  -25  4.8   3.907   3.697    70   17.4  18:28 ( 93, 52)  

* 12P/Pons-Brooks

It returns for the first time in 70 years. It brightened up to 3.7 mag in early April in 2024 (Apr. 6, 2024, Jose Guilherme Aguiar). Now it is 17.9 mag (Mar. 14, ATLAS Chile). Fading slowly. It will be fainter than 18 mag in June. 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)  
May  17  16 21.07  -50 41.5   4.117   4.997   147   17.5   0:45 (  0, 74)  
May  24  16 12.04  -50  5.8   4.154   5.061   150   17.6   0:08 (  0, 75)  

* C/2024 G6 ( ATLAS )

Now it is 16.9 mag (May 9, ATLAS South Africa). 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)  
May  17  16 48.35  -22 14.9   5.731   6.703   162   17.6   1:11 (180, 77)  
May  24  16 42.32  -21 30.2   5.688   6.690   170   17.5   0:38 (180, 77)  

* C/2024 B1 ( Lemmon )

It brightened up to 13.1 mag in autumn (Nov. 1, Thomas Lehmann). Now it is 16.9 mag (May 14, Ken-ichi Kadota). Fading gradually. It will be fainter than 18 mag in June. It stays observable in good condition.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May  17  17 18.78   10  5.1   2.346   3.196   141   17.6   1:41 (180, 45)  
May  24  17  8.66    8 59.3   2.372   3.263   146   17.8   1:04 (180, 46)  

* C/2023 V1 ( Lemmon )

Now it is 17.5 mag (Apr. 28, Yasukazu Ikari). It stays 18 mag for a while. In the Northern Hemisphere, it stays observable in good condition. In the Southern Hemisphere, it is not observable now, but it will appear in August.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May  17  18 28.89   62 34.1   4.987   5.111    91   17.7   2:50 (180, -8)  
May  24  18 11.78   63 14.1   4.965   5.107    92   17.6   2:06 (180, -8)  

* C/2024 G4 ( PanSTARRS )

Now it is 17.9 mag (May 5, Alfons Diepvens). 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)  
May  17  17  1.71   16 57.9   4.652   5.445   137   17.7   1:24 (180, 38)  
May  24  16 59.45   17 12.4   4.611   5.422   139   17.7   0:54 (180, 38)  

* C/2023 U1 ( Fuls )

Now it is 17.3 mag (Mar. 6, ATLAS Chile). It stays 18 mag for a while. In the Northern Hemisphere, it will never be observable after this. In the Southern Hemisphere, it will be getting higher gradually.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May  17   3 12.00  -47 52.2   5.548   5.242    67   17.8   5:21 (313, 23)  
May  24   3 14.76  -48  9.4   5.524   5.259    69   17.8   5:25 (311, 28)  

* P/2010 LH155

It brightened very rapidly up to 16.9 mag in spring (Mar. 30, ATLAS South Africa). Now it is 17.9 mag (May 14, Ken-ichi Kadota). Fading gradually. It will be fainter than 18 mag soon. In the Northern Hemisphere, it will be getting lower gradually. In the Southern Hemisphere, it stays observable in good condition.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
May  17  10 24.42    2 46.4   1.820   2.241   100   17.8  18:44 (180, 52)  
May  24  10 33.21    2 34.0   1.901   2.248    96   18.0  18:28 (179, 53)  

* C/2024 N4 ( Sarneczky )

Now it is 17.8 mag (Apr. 17, Taras Prystavski). It stays 18 mag for a while. In the Northern Hemisphere, it will be getting lower gradually. 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)  
May  17   8  8.19   53 39.8   5.883   5.479    61   17.9  18:31 (162, -2)  
May  24   8 14.95   52 30.2   5.967   5.488    57   17.9  18:28 (159, -3)  

* C/2022 U1 ( Leonard )

Now it is 17.6 mag (Apr. 26, Yasukazu Ikari). 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)  
May  17  19 22.42   15 58.0   4.926   5.414   113   17.9   3:44 (180, 39)  
May  24  19 16.33   15 57.3   4.872   5.449   119   17.9   3:11 (180, 39)  

* C/2023 H1 ( PanSTARRS )

Now it is 16.7 mag (May 13, ATLAS South Africa). 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)  
May  17  20 19.39  -20 23.3   4.156   4.654   113   17.9   4:41 (180, 75)  
May  24  20 19.84  -19 58.2   4.080   4.671   120   17.9   4:14 (180, 75)  

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