Weekly Information about Bright Comets (2021 Oct. 2: North)

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Updated on October 6, 2021
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Best time and the azimuth, altitude (A,h) are at lat. 35 deg in the Northern Hemisphere.
Azimuth indicates 0 for south, 90 for west, 180 for north, 270 for east.

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* 8P/Tuttle

It brightened very rapidly. Now it is very bright as 8.9 mag (Sept. 11, Chris Wyatt). It stays bright as 8-9 mag until October. The condition is bad in this apparition. In the Southern Hemisphere, it stays observable after this while the comet will be fading. But it stays locating low. It is not observable after this in the Northern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  10 39.55  -22 24.3   1.857   1.157    33    8.7   4:31 (293, -6)  
Oct.  9  11  4.47  -27 16.7   1.896   1.208    34    8.9   4:37 (298, -7)  

* 67P/Churyumov-Gerasimenko

Now it is bright as 10.4 mag (Oct. 1, Osamu Miyazaki). It will brighten up to 9 mag, and will be observable in good condition in winter.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2   5  3.35   21 41.1   0.495   1.272   111   10.4   4:20 (  0, 77)  
Oct.  9   5 35.06   23 16.1   0.468   1.248   111   10.1   4:24 (  0, 78)  

* 6P/d'Arrest

Now it is bright as 11.7 mag (Sept. 21, Thomas Lehmann). It is observable at 10 mag in good condition from October to December. In the Northern Hemisphere, it locates somewhat low at the high light.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  18 47.20  -27 43.0   0.898   1.365    91   10.6  19:06 ( 15, 25)  
Oct.  9  19 13.82  -29 33.9   0.939   1.377    90   10.3  18:57 ( 13, 24)  

* 4P/Faye

Now it is bright as 11.0 mag (Sept. 28, Osamu Miyazaki). It stays observable at 10-11 mag in excellent condition from summer to autumn.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2   6  3.99   16  6.2   1.167   1.636    97   10.3   4:31 (326, 68)  
Oct.  9   6 17.28   15  7.7   1.130   1.648   101   10.3   4:37 (339, 69)  

* C/2019 L3 ( ATLAS )

Now it is 10.8 mag (Sept. 28, Osamu Miyazaki). It stays bright as 10 mag until spring for a long time. In the Northern Hemisphere, it stays observable in good condition for a long time. In the Southern Hemisphere, it locates extremely low until November.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2   7 30.87   43  2.4   3.676   3.668    81   10.8   4:31 (243, 62)  
Oct.  9   7 36.27   42 27.7   3.565   3.653    87   10.7   4:37 (243, 67)  

* C/2021 O1 ( Nishimura )

It was observed at 9-10 mag from late July to early August. Now it is not observable. It will appear in the morning sky in December, but it will be fainter than 15 mag at that time.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  12 49.61    3 28.0   2.185   1.203     8   11.5  19:06 (101,-10)  
Oct.  9  13 10.05    0 13.6   2.281   1.295     7   11.9  18:57 ( 98,-12)  

* C/2017 K2 ( PanSTARRS )

Now it is 11.7 mag (Sept. 29, Osamu Miyazaki). 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 autumn to 2023 summer. In the Southern Hemisphere, it stays low for a while. 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)  
Oct.  2  16 59.96   26 13.6   5.432   5.195    71   11.8  19:06 ( 88, 52)  
Oct.  9  17  2.24   24 50.8   5.441   5.134    67   11.8  18:57 ( 89, 49)  

* C/2020 T2 ( Palomar )

Now it is very bright as 10.9 mag (Sept. 8, Chris Wyatt). It will be fading after this. In the Northern Hemisphere, it will be getting lower gradually in the evening. In the Southern Hemisphere, it stays observable in good condition for a while.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  16 19.15  -24 13.8   2.636   2.277    58   11.9  19:06 ( 48, 12)  
Oct.  9  16 34.03  -25 45.8   2.734   2.313    55   12.1  18:57 ( 47, 11)  

* 19P/Borrelly

Now it is 14.6 mag (Sept. 11, Chris Wyatt). It will brighten rapidly up to 9 mag in winter. It will be observable in good condition. In the Southern Hemisphere, it is observable in excellent condition. In the Northren Hemisphere, it is not observable until November.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  23 27.38  -58 42.4   1.233   1.904   116   12.9  22:41 (  0, -4)  
Oct.  9  23 17.94  -57 57.3   1.220   1.852   112   12.6  22:05 (  0, -3)  

* C/2021 A1 ( Leonard )

Now it is 13.1 mag (Sept. 20, Ken-ichi Kadota). It will approach to Earth down to 0.2 a.u. in December, and it is expected to brighten up to 4 mag. In the Northern Hemisphere, it stays observable in good condition for a long time until December while the comet is brightening gradually, although it became extremely low temporarily in September. In the Southern Hemisphere, it is not observable until mid December.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  11 19.45   37 37.2   2.420   1.843    44   13.1   4:31 (237, 19)  
Oct.  9  11 25.94   36 53.9   2.240   1.740    48   12.7   4:37 (241, 24)  

* 15P/Finlay

It brightened very rapidly up to 10.7 mag in July (July 20, Osamu Miyazaki). Now it is fading. It has already faded down to 13.3 mag (Sept. 19, Seiichi Yoshida). It stays observable in the morning sky for a long time.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2   8 10.57   26 22.0   1.499   1.487    69   13.2   4:31 (270, 51)  
Oct.  9   8 23.65   26  8.7   1.500   1.552    73   13.7   4:37 (274, 55)  

* C/2019 T4 ( ATLAS )

Now it is 14.6 mag (July 12, Chris Wyatt). It is expected to brighten up to 11.5 mag in 2022. In the Southern Hemisphere, it stas observable in good condition for a long time, although it became extremely low temporarily from August to September. In the Northern Hemisphere, it is not observable until November.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  10 43.56  -24  7.5   5.523   4.718    33   13.3   4:31 (294, -8)  
Oct.  9  10 51.14  -24 32.5   5.472   4.694    35   13.3   4:37 (298, -3)  

* 29P/Schwassmann-Wachmann 1

Major outburst occured on Sept. 25. Now it is very bright as 11.0 mag (Oct. 1, Osamu Miyazaki).

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2   4 57.75   31 54.5   5.473   5.918   111   13.5   4:16 (  0, 87)  
Oct.  9   4 57.44   32  2.1   5.376   5.920   118   13.4   3:48 (  0, 87)  

* C/2020 J1 ( SONEAR )

It brightened up to 12.3 mag from spring to summer (June 15, Marco Goiato). Now it is fading. It has already faded down to 13.8 mag (Sept. 8, Chris Wyatt). Now it is not observable. It will be observable again at 14 mag in November in the Northern Hemisphere, or in January in the Southern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  13 54.94   -2 56.3   4.615   3.696    20   13.8  19:06 ( 87, -1)  
Oct.  9  13 58.05   -2 37.8   4.676   3.723    15   13.8  18:57 ( 89, -4)  

* 7P/Pons-Winnecke

It brightened up to 9.7 mag in June (June 4, Michael Jager). Now it is fading. It has already faded down to 14.1 mag (Sept. 11, Chris Wyatt). In the Southern Hemisphere, it stays observable in excellent condition for a long time. In the Northern Hemisphere, it becomes extremely low after this.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  23 17.82  -47 14.2   1.139   1.914   126   14.6  22:32 (  0,  8)  
Oct.  9  23 15.86  -45 23.4   1.230   1.968   123   15.0  22:03 (  0, 10)  

* C/2020 PV6 ( PanSTARRS )

Now it is 14.5 mag (Sept. 22, Thomas Lehmann). It stays 14 mag until October, and it is 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)  
Oct.  2  16 10.87   20 34.2   2.651   2.297    58   14.8  19:06 ( 88, 40)  
Oct.  9  16  8.44   19 36.5   2.749   2.300    53   14.9  18:57 ( 90, 35)  

* 246P/NEAT

Now it is 14.9 mag (Sept. 6, ATLAS-MLO, Mauna Loa). It stays 13-14 mag from 2020 to 2021. It will be observable in good condition after this in the Southern Hemisphere. It locates low in the Northern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  19  2.68  -34 50.7   2.856   3.096    94   14.8  19:06 ( 10, 19)  
Oct.  9  19  9.38  -34 34.5   2.963   3.109    88   14.9  18:57 ( 13, 19)  

* C/2020 F5 ( MASTER )

Now it is 14.8 mag (Sept. 11, Chris Wyatt). It stays 14-15 mag until the end of 2021. In the Southern Hemisphere, it stays observable in good condition for a long time. It locates low in the Northern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  22 36.54  -29 36.3   3.824   4.605   136   14.8  21:51 (  0, 26)  
Oct.  9  22 32.28  -28 38.9   3.912   4.625   130   14.9  21:19 (  0, 27)  

* 132P/Helin-Roman-Alu 2

Now it is 14.0 mag (Sept. 25, Michael Jager). It is observable at 14-15 mag in excellent condition in autumn.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2   0 23.05   -0 38.7   0.743   1.742   175   15.0  23:37 (  0, 54)  
Oct.  9   0 22.00   -1 37.1   0.737   1.727   168   14.9  23:09 (  0, 53)  

* 10P/Tempel 2

It brightened up to 10.1 mag in spring (Apr. 10, Marco Goiato). Now it is fading. It has already faded down to 15.3 mag (Sept. 9, Sandor Szabo). It stays observable in good condition for a long time after this while the comet will fading.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2   4 55.60    7 18.8   1.704   2.305   114   14.9   4:13 (  0, 62)  
Oct.  9   4 54.90    6 54.1   1.672   2.349   121   15.0   3:45 (  0, 62)  

* 22P/Kopff

Now it is not observable. In the Southern Hemisphere, it will appear in the morning sky at 11 mag in late January, then it stays observable at 11 mag until June. In the Northern Hemisphere, it will appear in the morning sky in December, but it stays locating extremely low for a long time.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  13 11.91   -4  6.3   3.202   2.223     9   15.1  19:06 ( 92,-10)  
Oct.  9  13 25.39   -5 28.7   3.169   2.181     6   14.9  18:57 ( 91,-12)  

* P/2021 Q5 ( ATLAS )

Bright new periodic comet. Now it is 13.9 mag (Sept. 15, Michael Jager). It stays observable in good condition for a long time. It stays 14-15 mag until November. Juan Jose Gonzalez reported it is very bright as 11.6 mag on Sept. 17.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2   8 46.28   13 13.4   1.497   1.294    58   15.0   4:31 (281, 38)  
Oct.  9   9  6.30   10 53.2   1.499   1.322    60   15.1   4:37 (286, 39)  

* 108P/Ciffreo

Now it is 14.1 mag (Sept. 15, Michael Jager). It stays 15 mag until November. It will be observable in excellent condition in the Northern Hemisphere. It locates somewhat low in the Southern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2   6 16.10   25 13.0   1.257   1.675    95   15.1   4:31 (302, 73)  
Oct.  9   6 30.49   26 14.1   1.213   1.685    98   15.1   4:37 (310, 77)  

* C/2019 F1 ( ATLAS-Africano )

Now it is 14.8 mag (Sept. 11, Chris Wyatt). It was expected to brighten up to 13 mag from spring to summer. But actually, it is fainter than originally expected. It stays 14-15 mag until early autumn. In the Southern Hemisphere, it stays observable in good condition for a long time. In the Northern Hemisphere, it is not observable until July in 2022.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  20 58.36  -79 47.2   3.527   3.711    92   15.1  20:16 (  0,-25)  
Oct.  9  21  7.75  -78  7.0   3.585   3.727    90   15.2  19:57 (  0,-23)  

* C/2018 U1 ( Lemmon )

Now it is 15.2 mag (Sept. 8, Chris Wyatt). It stays at 14-15 mag for a long time from 2021 to 2022. It will be unobservable from November to January.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  16 22.01  -18 24.1   5.455   4.999    58   15.2  19:06 ( 52, 17)  
Oct.  9  16 23.51  -19 16.5   5.554   4.997    51   15.2  18:57 ( 54, 14)  

* 9P/Tempel 1

It will brighten up to 12 mag from winter to spring. Now it is not observable. In the Northern Hemisphere, it will appear in the morning sky at 14 mag in November. In the Southern Hemisphere, it is not observable until January.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  11 58.34    7 50.4   3.058   2.102    14   15.4   4:31 (257, -5)  
Oct.  9  12 12.80    6 12.1   3.000   2.063    16   15.2   4:37 (261, -2)  

* C/2020 Y2 ( ATLAS )

Now it is 16.0 mag (Aug. 16, iTelescope Observatory, Siding Spring). It is expected to brighten up to 13 mag in 2022. In the Southern Hemisphere, it stays observable in good condition for a long time, although it becomes extremely low temporarily from September to October. In the Northern Hemisphere, it is not observable for a while.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  12 21.77  -29 14.7   4.856   3.979    25   15.4   4:31 (287,-29)  
Oct.  9  12 25.17  -30 27.5   4.819   3.940    25   15.4   4:37 (291,-24)  

* 284P/McNaught

Now it is 14.7 mag (Sept. 11, Chris Wyatt). It stays 15 mag until October, and it is observable in good condition.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  23  3.97  -16 21.1   1.375   2.300   150   15.4  22:19 (  0, 39)  
Oct.  9  23  2.69  -16 52.8   1.422   2.303   143   15.5  21:50 (  0, 38)  

* 117P/Helin-Roman-Alu 1

Now it is 15.7 mag (Aug. 30, Thomas Lehmann). In the Northern Hemisphere, it is not observable now. It will be unobservable soon also in the Southern Hemisphere. It will appear in the morning sky at 15 mag in January. Then It will brighten up to 13 mag in 2022 summer.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  14 26.96  -13  3.4   4.154   3.324    29   15.5  19:06 ( 74,  0)  
Oct.  9  14 36.16  -13 57.9   4.186   3.312    25   15.5  18:57 ( 75, -3)  

* C/2020 R7 ( ATLAS )

Now it is 16.2 mag (Sept. 18, Thomas Lehmann). It will brighten up to 12.5 mag in 2022 summer. In the Southern Hemisphere, it stays observable in excellent condition for a long time. In the Northern Hemisphere, it is not observable until August in 2022.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2   3  8.68  -72 22.2   4.177   4.464   100   15.6   2:26 (  0,-17)  
Oct.  9   2 43.48  -74  6.1   4.165   4.418    98   15.5   1:34 (  0,-19)  

* 252P/LINEAR

It brightened up to 4 mag in major outburst in 2016. In this apparition, it brightened up to 10.5 mag in early August (Aug. 8, Rob Kaufman). Now it is fading rapidly. It has already faded down to 14.0 mag (Aug. 31, Chris Wyatt). In the Southern Hemisphere, it stays locating low in the evening sky until October. In the Northern Hemisphere, it stays locating extremely low.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  15  8.06  -10 53.3   2.117   1.485    39   15.6  19:06 ( 69,  9)  
Oct.  9  15 30.65  -12  8.4   2.203   1.547    38   16.2  18:57 ( 68,  9)  

* C/2020 M5 ( ATLAS )

Now it is 15.4 mag (Sept. 8, Thomas Lehmann). In the Northern Hemisphere, it stays observable at 15-16 mag for a long time until early 2022, although it becomes extremely low temporarily from September to October. In the Southern Hemisphere, it is not observable until the end of 2021.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  12 53.57   29 34.1   3.820   3.035    33   15.6  19:06 (122,  6)  
Oct.  9  12 57.43   27 48.5   3.822   3.045    33   15.7   4:37 (238,  3)  

* 106P/Schuster

Now it is 15.8 mag (Sept. 3, Michael Jager). It will be fading after this, and it will be fainter than 18 mag in December. In the Northern Hemisphere, it stays observable in good condition for a long time. In the Southern Hemisphere, it will be getting lower gradually after this.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2   7 23.50   30 12.9   1.420   1.600    80   15.7   4:31 (271, 62)  
Oct.  9   7 41.76   31 24.3   1.390   1.623    83   15.9   4:37 (271, 66)  

* 110P/Hartley 3

Brightening rapidly. Now it is 16.3 mag (Sept. 12, ATLAS-MLO, Mauna Loa). It will be observable at 15 mag in excellent condition in winter.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2   7 44.98   24 41.3   2.518   2.458    75   15.9   4:31 (277, 56)  
Oct.  9   7 55.15   23 57.7   2.434   2.456    79   15.8   4:37 (283, 60)  

* C/2019 U5 ( PanSTARRS )

Now it is 15.9 mag (Sept. 13, ATLAS-MLO, Mauna Loa). It is expected to brighten up to 11 mag in 2023. In the Northern Hemisphere, it stays observable in good condition for a long time. It is not observable in the Southern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  16  5.80   37 25.5   6.272   5.905    64   15.8  19:06 (110, 45)  
Oct.  9  16  6.66   36 25.7   6.274   5.862    61   15.8  18:57 (110, 42)  

* C/2021 A7 ( NEOWISE )

It brightened up to 14.2 mag in early summer (June 10, Thomas Lehmann). Now it is fading. In the Northern Hemisphere, it is appearing in the morning sky. In the Southern Hemisphere, it will never be observable again.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  12  6.84   24 11.2   3.016   2.187    28   15.8   4:31 (243,  4)  
Oct.  9  12 22.25   25  7.9   3.003   2.225    32   15.9   4:37 (245,  7)  

* 2010 OE101

Michael Jager detected its cometary activity on Sept. 25. Now it is bright as 16.2 mag (Sept. 25, Michael Jager). It approaches to Earth down to 0.35 a.u. in early October, and it is observable at 16 mag in excellent condition.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  23 56.07    9 30.9   0.353   1.349   169   16.0  23:12 (  0, 64)  
Oct.  9   0  9.25    3 38.3   0.357   1.350   167   16.0  22:57 (  0, 58)  

* C/2021 E3 ( ZTF )

Now it is 16.2 mag (Sept. 22, Thomas Lehmann). It is expected to brighten up to 11 mag from spring to summer in 2022. In the Southen Hemisphere, it locates somewhat low in 2021, but it will be observable in good condition at the high light for a long time. In the Northern Hemisphere, it is observable in good condition in 2021, but it will not be observable at the high light.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  18 37.19   15 51.4   3.310   3.494    92   16.0  19:06 ( 45, 65)  
Oct.  9  18 35.75   13 27.9   3.349   3.430    86   16.0  18:57 ( 50, 60)  

* 17P/Holmes

Outburst occured in early August. Now it is 15.5 mag (Sept. 23, Thomas Lehmann). In the Northern Hemisphere, it stays observable in good condition. In the Southern Hemipsphere, it stays locating extremely low after this.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2   5 52.01   45 18.2   2.299   2.655    99   16.0   4:31 (213, 77)  
Oct.  9   5 56.45   46  0.7   2.245   2.683   105   16.2   4:37 (189, 79)  

* 104P/Kowal 2

Now it is 18.2 mag (Sept. 25, Michael Jager). It will brightens rapidly. And it is expected to be observable at 12-13 mag in good condition from December to February.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  21 48.14   -5 34.9   0.784   1.669   138   16.4  21:03 (  0, 49)  
Oct.  9  21 43.48   -6 47.8   0.774   1.609   129   16.1  20:31 (  0, 48)  

* C/2020 O2 ( Amaral )

Now it is 15.7 mag (Sept. 9, Toshihiko Ikemura, Hirohisa Sato). It will be unobservable in November.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  16 43.83   -9 10.9   5.246   4.870    62   16.1  19:06 ( 54, 28)  
Oct.  9  16 47.84   -8 45.5   5.343   4.873    57   16.2  18:57 ( 57, 26)  

* C/2021 D2 ( ZTF )

Now it is 17.9 mag (Sept. 12, Thomas Lehmann). It will brighten up to 15.5 mag in winter. In the Northern Hemisphere, it stays observable in good condition for a long time. It is not observable at all in the Southern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  15 39.10   65 18.8   3.278   3.198    76   16.3  19:06 (149, 42)  
Oct.  9  15 38.17   64 19.2   3.252   3.172    76   16.3  18:57 (148, 41)  

* C/2019 T2 ( Lemmon )

It was expected to brighten up to 14.5 mag from spring to summer. But actually, it is fainter than expected. Now it is 17.7 mag (July 4, Mount John Observatory, Lake Tekapo). In the Southern Hemisphere, it stays observable in excellent condition for a long time. In the Northern Hemisphere, it is not observable after this.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  11 21.05  -51 48.5   3.680   3.141    50   16.3   4:31 (316,-28)  
Oct.  9  11 28.95  -51 36.8   3.744   3.180    49   16.4   4:37 (317,-24)  

* 402P/2020 Q3 ( LINEAR )

First return of a new periodic comet observed at 16 mag from 2003 to 2004. Now it is 17.5 mag (Sept. 5, ATLAS-HKO, Haleakala). It will brighten up to 16 mag in winter, and it will be observable in excellent condition.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2   6 32.65    1 26.9   3.833   3.960    89   16.4   4:31 (327, 52)  
Oct.  9   6 35.89    1 15.1   3.733   3.956    95   16.3   4:37 (339, 54)  

* C/2020 K1 ( PanSTARRS )

Now it is 16.8 mag (Sept. 22, Thomas Lehmann). It is expected to brighten up to 11 mag in 2023. In the Northern Hemisphere, it is observable in good condition in 2021. But it is observable only until November in 2022. In the Southern Hemisphere, it locates extremely low in 2021. 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)  
Oct.  2  17 27.46   30 48.1   6.230   6.101    78   16.4  19:06 ( 92, 60)  
Oct.  9  17 29.21   29 29.5   6.248   6.053    74   16.4  18:57 ( 92, 56)  

* C/2019 N1 ( ATLAS )

It brightened up to 11.6 mag in winter (Feb. 18, Thomas Lehmann). Now it is fading. It has already faded down to 15.8 mag (Sept. 15, Thomas Lehmann). In the Southern Hemisphere, it stays observable in good condition after this. In the Northern Hemisphere, it will never be observable after this.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2   4 22.63  -69 16.5   3.709   3.968    97   16.4   3:40 (  0,-14)  
Oct.  9   4  0.13  -70  2.7   3.773   4.033    97   16.5   2:50 (  0,-15)  

* C/2019 T3 ( ATLAS )

Now it is 16.2 mag (Sept. 22, Thomas Lehmann). It is observable at 16 mag from 2020 to 2021. It locates low in the Southern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  21 45.64   35  6.9   5.439   6.133   130   16.4  21:00 (180, 90)  
Oct.  9  21 41.30   33 31.1   5.491   6.145   127   16.4  20:28 (  0, 89)  

* 57P/du Toit-Neujmin-Delporte

Now it is 16.7 mag (Sept. 12, ATLAS-HKO, Haleakala). It stays 16.5 mag until October.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  17 25.99  -20 28.3   1.722   1.726    73   16.4  19:06 ( 37, 25)  
Oct.  9  17 44.24  -20 47.8   1.771   1.722    70   16.4  18:57 ( 37, 25)  

* C/2021 K1 ( ATLAS )

Now it is 15.3 mag (Sept. 9, Sandor Szabo). It will be fading after this, and it will be fainter than 18 mag in November.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2   1  7.68  -13 13.4   1.920   2.885   161   16.5   0:26 (  0, 42)  
Oct.  9   1  4.49  -13 53.7   1.960   2.918   159   16.7  23:51 (  0, 41)  

* 193P/LINEAR-NEAT

Now it is 15.8 mag (Sept. 12, Thomas Lehmann). It stays observable at 16 mag in good condition until October.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  23  0.13    1 13.8   1.229   2.186   156   16.6  22:15 (  0, 56)  
Oct.  9  22 56.95    1 28.0   1.272   2.193   149   16.6  21:44 (  0, 57)  

* C/2019 O3 ( Palomar )

Now it is 16.6 mag (Sept. 8, Michael Jager). It stays at 16-17 mag from 2020 to 2021. In the Northern Hemisphere, it stays observable in good condition for a long time. In the Southern Hemisphere, it is not observable after this.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  18 19.66   49  6.1   8.835   8.901    90   16.7  19:06 (137, 68)  
Oct.  9  18 19.45   48 42.2   8.879   8.907    88   16.7  18:57 (132, 66)  

* 52P/Harrington-Abell

Now it is 17.0 mag (Sept. 9, Toshihiko Ikemura, Hirohisa Sato). It stays observable at 17 mag from autumn to winter. In the Northern Hemisphere, it stays observable in good condition. In the Southern Hemisphere, it stays extremely low until November.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2   9 38.10   19 46.1   2.273   1.777    48   16.8   4:31 (266, 30)  
Oct.  9   9 55.55   18  0.3   2.228   1.778    50   16.7   4:37 (270, 33)  

* 422P/2021 L1 ( Christensen )

First return of a new periodic comet which brightened up to 17 mag in 2006. Now it is 17.4 mag (Sept. 7, J. L. Virlichie, P. Traverse). It stays 17 mag from 2021 to 2022.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  21 29.75  -63 28.6   2.779   3.188   104   16.8  20:45 (  0, -8)  
Oct.  9  21 30.07  -61 47.3   2.827   3.177   101   16.8  20:18 (  0, -7)  

* C/2020 U5 ( PanSTARRS )

Now it is 17.6 mag (Sept. 11, Catalina Sky Survey). It will brighten up to 16 mag 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 2023.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2   8 50.52   55 45.3   4.334   4.177    74   16.9   4:31 (223, 48)  
Oct.  9   8 59.21   57 26.2   4.213   4.151    79   16.8   4:37 (220, 51)  

* 254P/McNaught

Now it is 16.9 mag (Sept. 19, Ken-ichi Kadota). It continues brightening even after the perihelion passage. It stays observable at 17 mag in good condition for a while.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2   5 11.52  -13 10.0   3.233   3.678   108   17.0   4:29 (  0, 42)  
Oct.  9   5 11.87  -13 51.6   3.177   3.696   113   16.9   4:02 (  0, 41)  

* C/2020 F7 ( Lemmon )

Now it is 17.7 mag (May 12, ATLAS-HKO, Haleakala). It brightened rapidly. It stays 17 mag for a long time from 2021 to 2022. In the Southern Hemisphere, it stays observable in good condition for a long time. In the Northern Hemisphere, it will be observable only in extremely low sky from autumn to winter.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2   9  6.11  -23 44.9   5.874   5.342    53   17.0   4:31 (308,  9)  
Oct.  9   9  7.61  -25 13.2   5.800   5.339    58   17.0   4:37 (314, 13)  

* P/2021 N2 ( Fuls )

Now it is 17.2 mag (Sept. 2, Michael Jager). It is observable at 17 mag in good condition in autumn.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2   2 28.75   17 36.3   2.919   3.805   148   17.1   1:47 (  0, 73)  
Oct.  9   2 26.37   17  6.8   2.870   3.803   155   17.1   1:17 (  0, 72)  

* C/2019 K7 ( Smith )

Now it is 16.7 mag (Sept. 12, Catalina Sky Survey). Fading slowly. In the Northern Hemisphere, it stays observable in good condition for a long time. It is not observable after this in the Southern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  16 14.32   49 39.4   6.075   5.833    71   17.2  19:06 (128, 48)  
Oct.  9  16 15.68   49  5.2   6.133   5.867    70   17.2  18:57 (127, 46)  

* 70P/Kojima

Now it is 17.4 mag (Aug. 28, Toshihiko Ikemura, Hirohisa Sato). It will brighten up to 15.5 mag, and will be observable in excellent condition in winter.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2   8 57.31   16  4.6   2.398   2.026    56   17.3   4:31 (276, 37)  
Oct.  9   9 12.69   15 13.9   2.331   2.019    59   17.2   4:37 (280, 40)  

* 2012 US136

Peculiar asteroid moving along a cometary orbit. It brightens up to 17 mag from September to October. In the Northern Hemisphere, it is observable in excellent condition. It is not observable in the Southern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2   8  8.78   85 60.0   0.594   1.180    91   17.2   4:31 (184, 38)  
Oct.  9  21 25.81   84 49.2   0.679   1.295    99   17.5  20:08 (180, 41)  

* 28P/Neujmin 1

Now it is 17.4 mag (Sept. 3, Michael Jager). In the Northern Hemisphere, it stays observable in good condition after this while the comet will be fading. In the Southern Hemisphere, it stays locating extremely low for a long time.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2   5 26.26   39 46.9   2.323   2.754   104   17.2   4:31 (208, 85)  
Oct.  9   5 27.14   40 29.0   2.291   2.810   111   17.2   4:18 (180, 85)  

* 241P/LINEAR

Now it is 17.2 mag (Sept. 8, Catalina Sky Survey). In the Northern Hemisphere, it stays observable at 17 mag in good condition until winter. In the Southern Hemisphere, it stays locating extremely low for a while.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2   8 12.88   32 22.9   2.119   2.027    70   17.2   4:31 (261, 53)  
Oct.  9   8 25.91   31 16.3   2.072   2.049    74   17.3   4:37 (265, 57)  

* C/2020 U4 ( PanSTARRS )

Now it is 18.1 mag (Sept. 11, ATLAS-HKO, Haleakala). It stays 17 mag for a long time from 2021 to 2022. It is observable in excellent condition in the Northern Hemisphere, It locates somewhat low in the Southern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2   5 22.36   33 36.0   5.166   5.532   106   17.4   4:31 (305, 88)  
Oct.  9   5 16.21   33 53.2   5.031   5.519   114   17.3   4:07 (  0, 89)  

* C/2017 U7 ( PanSTARRS )

Now it is 17.7 mag (Sept. 9, Toshihiko Ikemura, Hirohisa Sato). It will be fading slowly.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  16 52.22  -10 34.5   8.498   8.123    64   17.3  19:06 ( 51, 28)  
Oct.  9  16 52.78  -10 32.0   8.631   8.150    58   17.4  18:57 ( 55, 25)  

* 116P/Wild 4

Now it is 18.2 mag (Sept. 6, W. Hasubick). It will brighten rapidly, and it will be observable at 13.5 mag in good condition from winter to spring.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2   8 46.67   21 16.1   3.249   2.889    60   17.6   4:31 (272, 42)  
Oct.  9   8 56.41   20 42.8   3.140   2.864    64   17.4   4:37 (276, 46)  

* C/2021 O3 ( PanSTARRS )

Now it is 18.0 mag (Sept. 24, Michael Jager). It is expected to brighten up to 4.5 mag in 2022 April. However, it is not observable at the high light. In the Northern Hemisphere, it stays observable until early February when it brightens up to 14 mag. Then it will appear at 6 mag in mid May, and it stays observable in good condition after that while the comet will be fading. In the Southern Hemisphere, it stays observable until December when it brightens up to 16 mag. But after that, it is not observable until 2022 August.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  22 23.97   22 19.8   2.655   3.512   143   17.6  21:38 (  0, 77)  
Oct.  9  22 16.71   20 41.9   2.612   3.424   138   17.4  21:03 (  0, 76)  

* C/2020 S3 ( Erasmus )

It brightened up to 3 mag in December in the SOHO spacecraft images in 2020 December (Dec. 18, Hirohisa Sato). Now it is 16.5 mag (Sept. 5, Thomas Lehmann). It stays observable in good condition after this while the comet will be fading.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  23 22.41   15 10.8   3.530   4.480   159   17.5  22:37 (  0, 70)  
Oct.  9  23 17.66   14 18.1   3.636   4.556   154   17.6  22:04 (  0, 69)  

* 230P/LINEAR

Now it is 17.0 mag (Aug. 26, J. Drummond). It will brighten up to 16.5-17 mag in winter. In its last apparition in 2015, it brightened up to 13 mag.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  21 45.80  -33  6.0   1.490   2.234   126   17.6  21:01 (  0, 22)  
Oct.  9  21 44.39  -33  1.7   1.518   2.193   119   17.5  20:32 (  0, 22)  

* 119P/Parker-Hartley

Now it is 17.3 mag (Sept. 11, Purple Mountain Observatory, XuYi Station). It will brighten up to 15 mag in 2022 winter. In 2021, it stays observable in good condition while the comet will be brightening gradually.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  22 28.02  -18 59.6   2.241   3.093   142   17.6  21:43 (  0, 36)  
Oct.  9  22 25.17  -19  8.7   2.281   3.067   134   17.6  21:12 (  0, 36)  

* 424P/2021 L5 ( La Sagra )

First return of a new periodic comet which brightened up to 17 mag in 2012. Now it is 18.1 mag (Aug. 29, ATLAS-MLO, Mauna Loa). It is observable in excellent condition in the Southern Hemisphere. It locates low in the Northern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  20 15.38  -36 17.7   0.727   1.410   108   17.7  19:32 (  0, 19)  
Oct.  9  20 31.96  -34 23.9   0.736   1.390   105   17.7  19:21 (  0, 21)  

* 395P/2020 H1 ( Catalina-NEAT )

Now it is 17.4 mag (Sept. 9, Toshihiko Ikemura, Hirohisa Sato). It stays observable at 17-18 mag for a long time from 2021 to 2022.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  19 11.36  -18 59.1   3.829   4.092    98   17.7  19:06 ( 11, 35)  
Oct.  9  19 14.99  -18 57.3   3.928   4.088    92   17.8  18:57 ( 15, 35)  

* 430P/2021 Q2 ( Scotti )

First return of a new periodic comet which brightened up to 17 mag in 2011. Now it is 17.2 mag (Sept. 16, Catalina Sky Survey). It stays observable at 17 mag in good condition until 2022 spring.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2   9 32.52   17 41.8   2.137   1.663    49   17.9   4:31 (269, 31)  
Oct.  9   9 52.63   16 12.0   2.076   1.641    50   17.7   4:37 (272, 32)  

* C/2021 P4 ( ATLAS )

Now it is 17.8 mag (Sept. 12, S. Shurpakov). It is expected to brighten up to 11 mag in 2022 summer. In the Northern Hemisphere, it stays observable in good condition until 2022 June when it brightens up to 11 mag. But it is not observable after the high light. In the Souther Hemisphere, it is not observable until 2022 October.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2   0  2.49   63 12.1   3.534   4.127   120   17.9  23:16 (180, 62)  
Oct.  9  23 47.79   63 20.4   3.443   4.055   121   17.8  22:34 (180, 62)  

* 378P/2019 E2 ( McNaught )

Now it is 18.2 mag (Aug. 28, Toshihiko Ikemura, Hirohisa Sato). It has passed the perihelion in 2020 October. At the discovery in 2005, it stayed bright for several years even after the perihelion passage. In this apparition, it may stay observable at 18 mag from 2021 to 2024.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  23 23.13  -29 32.7   3.158   4.004   143   17.8  22:38 (  0, 26)  
Oct.  9  23 20.17  -29 29.3   3.234   4.026   137   17.8  22:07 (  0, 26)  

* C/2020 S4 ( PanSTARRS )

Now it is 18.3 mag (Sept. 9, Toshihiko Ikemura, Hirohisa Sato). It will brighten up to 14 mag in early 2023. It stays observable in good condition for a long time until spring.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2   4 54.84    3 43.8   5.049   5.538   114   17.9   4:13 (  0, 59)  
Oct.  9   4 54.98    3 29.9   4.914   5.493   120   17.9   3:45 (  0, 59)  

* 433P/(248370) 2005 QN173

Now it is 18.2 mag (Sept. 8, Michael Jager). Main-belt asteroid, but it has a long tail of 10 arcmin (Sept. 4, Michael Jager). It stays observable in good condition until winter.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Oct.  2  23 45.62   -1 34.2   1.498   2.485   167   19.3  23:00 (  0, 54)  
Oct.  9  23 41.25   -2  2.8   1.536   2.495   159   19.5  22:28 (  0, 53)  

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