Weekly Information about Bright Comets (2021 Apr. 3: North)

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Updated on April 5, 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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* C/2020 R4 ( ATLAS )

It brightened rapidly in December. Now it is bright as 8.9 mag (Mar. 26, Michael Mattiazzo). It will approach to Earth down to 0.46 a.u. in April, and it will be observable at 8.5 mag in excellent condition.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3  19 41.97    0  2.6   0.861   1.159    76    9.1   4:18 (304, 39)  
Apr. 10  19  5.93    6 38.8   0.671   1.216    91    8.9   4:07 (313, 52)  

* 10P/Tempel 2

Now it is 10.6 mag (Mar. 25, Chris Wyatt). Appearing in the morning sky in the Southern Hemisphere. In the Northern Hemisphere, it will appear in the morning sky in June.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3  22 56.94   -9 57.9   2.167   1.416    31   11.6   4:18 (279, -4)  
Apr. 10  23 19.24   -8 21.8   2.157   1.424    32   11.6   4:07 (277, -5)  

* C/2020 T2 ( Palomar )

It brightened rapidly. Now it is very bright as 12.5 mag (Mar. 24, Chris Wyatt). It stays observable at 11 mag in good condition for a long time from spring to summer.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3  14  3.05   34 19.8   1.535   2.365   136   11.9   1:19 (  0, 89)  
Apr. 10  13 59.35   34 24.2   1.495   2.326   136   11.7   0:48 (  0, 89)  

* C/2021 D1 ( SWAN )

It brightened up to 10.5 mag in early March (Mar. 8, Bob King). Now it is fading. In the Northern Hemisphere, it stays observable in the evening low sky until early June while the comet will be fading. It is not observable in the Southern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3   2 25.89   31 30.6   1.747   1.088    34   12.1  19:48 (118, 16)  
Apr. 10   3  5.15   33 11.4   1.807   1.159    36   12.4  19:55 (119, 18)  

* C/2019 N1 ( ATLAS )

It brightened up to 11.6 mag in winter (Feb. 18, Thomas Lehmann). Now it is fading. But it is still bright as 13.5 mag (Mar. 25, Chris Wyatt). 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)  
Apr.  3   3 45.54  -68 18.0   2.271   2.312    79   12.9  19:48 ( 23,-26)  
Apr. 10   3 55.22  -65  9.9   2.350   2.370    78   13.0  19:55 ( 28,-27)  

* C/2019 L3 ( ATLAS )

Now it is 13.2 mag (Mar. 29, Thomas Lehmann). It will brighten up to 10 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 November.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3   2 23.66   51  5.9   4.934   4.359    50   12.9  19:48 (136, 25)  
Apr. 10   2 36.54   50 59.5   4.954   4.324    46   12.9  19:55 (138, 22)  

* C/2019 F1 ( ATLAS-Africano )

Now it is 14.8 mag (Mar. 25, Chris Wyatt). It is expected to brighten up to 13 mag from spring to summer. But actually, it is fainter than this ephemeris recently. 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)  
Apr.  3  19 12.15  -67  1.9   3.488   3.670    92   13.4   4:18 (347,-15)  
Apr. 10  19 28.46  -68 45.4   3.415   3.658    96   13.3   4:07 (348,-16)  

* C/2017 K2 ( PanSTARRS )

Now it is 13.3 mag (Mar. 17, Toshihiko Ikemura, Hirohisa Sato). 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 stays extremely 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)  
Apr.  3  18 28.06   39 35.2   6.626   6.711    90   13.4   4:18 (249, 73)  
Apr. 10  18 27.43   40 13.3   6.515   6.655    93   13.3   4:07 (244, 76)  

* C/2021 A4 ( NEOWISE )

It brightening very rapidly up to 12.5 mag in early February (Feb. 8, Michael Jager). Now it is fading. But it is still bright as 13.0 mag (Mar. 27, Thomas Lehmann). In the Northern Hemisphere, it is observable only until early April. In the Southern Hemisphere, it stays observable after this while the comet will be fading.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3   4 12.18   -7 58.7   1.465   1.167    52   13.5  19:48 ( 69, 15)  
Apr. 10   4 12.22  -10 10.3   1.605   1.192    47   14.1  19:55 ( 73,  6)  

* 246P/NEAT

Now it is 15.0 mag (Mar. 20, F. Kugel, J.-G. Bosch). It stays 13-14 mag from 2020 to 2021. It will be observable in good condition after this 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)  
Apr.  3  19  2.55  -24 13.2   2.711   2.872    88   13.9   4:18 (330, 24)  
Apr. 10  19  9.42  -24 35.0   2.621   2.875    94   13.8   4:07 (332, 25)  

* 7P/Pons-Winnecke

Now it is 13.5 mag (Mar. 28, Thomas Lehmann). Brightenening very rapidly. It will brighten up to 11 mag from May to August. In the Southern Hemisphere, it stays observable in excellent condition for a long time. In the Northern Hemisphere, it stays observable in good condition for a while. But it becomes extremely low after July.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3  17 57.21    8 55.4   0.795   1.399   101   14.2   4:18 (332, 61)  
Apr. 10  18 19.41    8 15.9   0.734   1.362   102   13.9   4:07 (330, 60)  

* 29P/Schwassmann-Wachmann 1

Now it is 13.2 mag (Mar. 6, Thomas Lehmann). It is already unobservable in the Southern Hemisphere. It will be unobservable in April also in the Northern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3   2 56.18   25 12.5   6.642   5.869    36   13.9  19:48 (109, 18)  
Apr. 10   3  1.76   25 29.4   6.706   5.871    31   13.9  19:55 (112, 13)  

* C/2020 J1 ( SONEAR )

Now it is 13.3 mag (Mar. 24, Chris Wyatt). It stays 13.5 mag until early summer. In the Southern Hemisphere, it stays observable in good condition for a long time. It is getting higher slowly also in the Northern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3  17 13.14  -38 32.0   2.856   3.358   111   14.0   4:18 (358, 16)  
Apr. 10  16 59.95  -37 51.9   2.728   3.356   121   13.9   3:48 (  0, 17)  

* C/2020 K5 ( PanSTARRS )

It was expected to brighten up to 13 mag from spring to summer. But actually, now it is extremely faint as 19.0 mag (Mar. 22, A. C. Gilmore, P. M. Kilmartin). In the Southern Hemisphere, it stays observable in good condition for a long time. 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)  
Apr.  3  21 24.71  -38 55.0   1.950   1.766    64   14.4   4:18 (315, -5)  
Apr. 10  21 54.29  -41  1.2   1.846   1.721    66   14.2   4:07 (315, -9)  

* C/2019 T4 ( ATLAS )

Now it is 14.6 mag (Mar. 26, Thomas Lehmann). It is expected to brighten up to 11.5 mag in 2022. It is observable in excellent condition in the Southern Hemisphere. In the Northern Hemisphere, it is observable in the low sky until May.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3   8  0.16  -33 21.9   5.119   5.508   107   14.4  19:48 (  8, 21)  
Apr. 10   8  1.82  -32 17.2   5.140   5.473   104   14.3  19:55 ( 15, 21)  

* 156P/Russell-LINEAR

Brightened rapidly, and it brightened up to 9.7 mag in November (Nov. 15, Chris Wyatt). Now it is fading. It has already faded down to 14.1 mag (Mar. 29, Thomas Lehmann). In the Northern Hemisphere, it stays observable in good condition for a long time. In the Southern Hemisphere, it locates extremely low after this.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3   5 47.36   40 27.7   1.999   1.991    75   14.9  19:48 (112, 57)  
Apr. 10   6  6.80   40  2.2   2.112   2.041    72   15.2  19:55 (112, 54)  

* C/2020 S3 ( Erasmus )

It brightened up to 5.6 mag in early December (Dec. 9, Marco Goiato). In mid December, it was visible at about 3 mag in the SOHO spacecraft images (Dec. 18, Hirohisa Sato). It is appearing in the morning sky soon.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3  23 16.74    8 34.4   3.098   2.212    23   14.9   4:18 (261,  2)  
Apr. 10  23 26.10    9 44.4   3.165   2.315    26   15.1   4:07 (261,  4)  

* 4P/Faye

It has not been observed yet in this apparition. It will brighten up to 10 mag from summer to autumn, and it will be observable in excellent condition. It is appearing in the morning sky soon.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3  22 35.71   -4  0.5   2.988   2.236    34   15.2   4:18 (277,  3)  
Apr. 10  22 49.82   -2 42.0   2.903   2.194    37   15.0   4:07 (276,  5)  

* 88P/Howell

It brightened up to 8.2 mag in autumn (Oct. 13, Chris Wyatt). It faded down to 13.0 mag in February (Feb. 14, Sandor Szabo). It is not observable after this.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3   1 36.43    8 35.6   3.267   2.300    12   15.0  19:48 (106, -7)  
Apr. 10   1 49.21    9 54.0   3.331   2.346     8   15.2  19:55 (110,-10)  

* C/2019 T2 ( Lemmon )

It will brighten up to 14.5 mag from spring to summer. 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)  
Apr.  3  23 32.08  -46 55.4   3.101   2.654    54   15.1   4:18 (309,-29)  
Apr. 10  23 46.78  -48 43.5   3.009   2.649    59   15.0   4:07 (311,-30)  

* C/2021 A2 ( NEOWISE )

It brightened up to 10.5 mag in early February (Feb. 6, Marco Goiato). Now it is fading rapidly. It has already faded down to 15.6 mag (Mar. 29, Thomas Lehmann). In the Northern Hemisphere, it stays observable for a long time after this. In the Southern Heimsphere, it will never be observable again.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3   4 59.54   49 26.6   1.822   1.729    68   15.1  19:48 (128, 49)  
Apr. 10   5  1.98   51  0.8   1.990   1.786    63   15.5  19:55 (130, 44)  

* C/2020 F5 ( MASTER )

Now it is 15.8 mag (Jan. 14, Slooh.com Chile Observatory, La Dehesa). It stays 14-15 mag until the end of 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.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3  22 55.65  -40 41.5   4.859   4.327    52   15.1   4:18 (306,-21)  
Apr. 10  23  2.84  -39 48.5   4.800   4.328    56   15.1   4:07 (306,-19)  

* C/2018 U1 ( Lemmon )

Now it is 14.7 mag (Mar. 12, D. Buczynski). It will stay at 14-15 mag for a long time from 2021 to 2022. It stays observable in good condition after this while brightening gradually.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3  18 21.29    1 45.2   5.046   5.256    96   15.2   4:18 (327, 52)  
Apr. 10  18 19.11    1 33.2   4.916   5.240   103   15.2   4:07 (334, 54)  

* C/2021 A7 ( NEOWISE )

Now it is 14.7 mag (Mar. 26, Thomas Lehmann). It stays 15 mag until summer. In the Southern Hemisphere, it stays observable in good condition until June. In the Northern Hemisphere, it is observable in the low sky from March to May.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3   6 26.53  -32  3.2   2.137   2.330    88   15.3  19:48 ( 28, 17)  
Apr. 10   6 35.95  -27 46.9   2.139   2.287    85   15.2  19:55 ( 35, 18)  

* 17P/Holmes

Now it is 15.8 mag (Jan. 16, Slooh.com Canary Islands Observatory). It is not observable until June.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3   0 17.09   10 58.8   3.084   2.106     9   15.3   4:18 (250, -8)  
Apr. 10   0 31.25   13  0.9   3.086   2.115    11   15.3   4:07 (249, -7)  

* C/2017 T2 ( PanSTARRS )

It had been observed as 8-9 mag for a long time in 2020. Now it is fading. It has already faded down to 16.4 mag (Mar. 27, Thomas Lehmann). It will be observable in good condition after this in the Southern Hemisphere. It locates extremely low after this in the Northern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3  17 46.15  -38 58.0   3.876   4.252   105   15.4   4:18 (351, 15)  
Apr. 10  17 44.25  -40  0.0   3.837   4.317   112   15.4   4:07 (355, 15)  

* 117P/Helin-Roman-Alu 1

Now it is 15.2 mag (Mar. 24, F. Kugel, J.-G. Bosch). It will brighten up to 13 mag in 2022. In 2021, it is observable at 15-16 mag in good condition.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3  13 29.33   -1  7.1   2.717   3.704   169   15.4   0:45 (  0, 54)  
Apr. 10  13 24.71   -0 47.1   2.693   3.688   172   15.4   0:13 (  0, 54)  

* C/2019 K7 ( Smith )

Now it is 15.4 mag (Mar. 16, Toshihiko Ikemura, Hirohisa Sato). It stays 15-16 mag until spring. In the Northern Hemisphere, it stays observable in good condition for a long time. In the Southern Hemisphere, it will be observable in the extremely low sky only in next spring.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3  19 21.22   40 36.5   5.116   5.047    80   15.6   4:18 (248, 62)  
Apr. 10  19 19.39   42 32.2   5.083   5.073    83   15.7   4:07 (243, 66)  

* C/2020 M5 ( ATLAS )

Now it is 16.3 mag (Mar. 18, Toshihiko Ikemura, Hirohisa Sato). In the Northern Hemisphere, it stays observable at 15 mag for a long time from spring to early 2022. 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)  
Apr.  3  20 17.87   63 21.3   3.406   3.301    75   15.9   4:18 (211, 49)  
Apr. 10  20 13.70   66 13.4   3.352   3.273    76   15.9   4:07 (205, 50)  

* C/2020 M3 ( ATLAS )

It brightened up to 7.3 mag in November (Nov. 7, Marco Goiato). Now it is fading. It has already faded down to 16.0 mag (Mar. 17, Toshihiko Ikemura, Hirohisa Sato). In the Northern Hemisphere, it stays observable in excellent condition for a long time. In the Southern Hemisphere, it stays locating extremely low after this.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3   7 10.53   44 36.4   2.306   2.517    90   15.9  19:48 (127, 71)  
Apr. 10   7 22.73   43 52.1   2.457   2.590    86   16.2  19:55 (121, 68)  

* 28P/Neujmin 1

Now it is not observable. It will be observable in June. But it will fade down to 17 mag at that time.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3  23 51.25   -0 37.5   2.542   1.600    15   15.9   4:18 (264,-10)  
Apr. 10   0  9.39    2  6.2   2.547   1.617    17   15.9   4:07 (261, -9)  

* 409P/2020 V1 ( LONEOS-Hill )

First return of a new periodic comet which brightened up to 14-15 mag in 2006. Now it is 15.3 mag (Mar. 18, Toshihiko Ikemura, Hirohisa Sato). It will be fading rapidly after this, and it will be fainter than 18 mag in May.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3  13 19.96   20 25.3   0.943   1.890   153   16.1   0:36 (  0, 75)  
Apr. 10  13 18.63   21 16.9   0.981   1.919   150   16.3   0:07 (  0, 76)  

* C/2020 Y2 ( ATLAS )

Now it is 16.3 mag (Mar. 16, Toshihiko Ikemura, Hirohisa Sato). 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. In the Northern Hemisphere, it stays observable until June, but it will not be observable at the high light.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3  13 25.83  -20 39.8   4.161   5.121   162   16.2   0:42 (  0, 34)  
Apr. 10  13 17.36  -20 48.8   4.093   5.075   167   16.1   0:06 (  0, 34)  

* C/2020 N1 ( PanSTARRS )

Now it is 16.0 mag (Mar. 10, Toshihiko Ikemura, Hirohisa Sato). It will be fading after this. In the Northern Hemisphere, it will be getting lower gradually, and will be too low to observe in May. It will be getting higher gradually in the Southern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3   5 18.65   10 38.7   1.392   1.360    67   16.2  19:48 ( 73, 39)  
Apr. 10   5 43.45    8 34.2   1.439   1.389    66   16.3  19:55 ( 73, 36)  

* C/2018 N2 ( ASASSN )

Now it is 15.4 mag (Mar. 17, Toshihiko Ikemura, Hirohisa Sato). In the Northern Hemisphere, it stays observable for a long time while it is getting fainter slowly. In the Southern Hemisphere, it will never be observable again.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3  15 45.18   69 19.7   5.332   5.587    99   16.2   3:00 (180, 56)  
Apr. 10  15 30.52   69 37.3   5.390   5.635    99   16.2   2:18 (180, 55)  

* C/2020 H6 ( ATLAS )

Now it is 15.5 mag (Mar. 14, Toshihiko Ikemura, Hirohisa Sato). It stays observable at 16 mag from 2021 to 2022.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3  14 16.33  -18 23.0   3.993   4.916   154   16.4   1:32 (  0, 36)  
Apr. 10  14 12.16  -16 56.8   3.933   4.900   163   16.4   1:01 (  0, 38)  

* C/2020 S8 ( Lemmon )

Now it is 16.2 mag (Mar. 16, Toshihiko Ikemura, Hirohisa Sato). It stays observable at 16 mag in good condition from April to May.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3  15 31.87   15 53.0   1.556   2.366   134   16.6   2:48 (  0, 71)  
Apr. 10  15  6.10   15 10.9   1.479   2.364   143   16.5   1:55 (  0, 70)  

* C/2019 T3 ( ATLAS )

Now it is 16.5 mag (Feb. 9, Toshihiko Ikemura, Hirohisa Sato). It is observable at 16 mag from 2020 to 2021. In the Southern Hemisphere, it is not observable until summer.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3  23  6.02   42 34.0   6.633   5.951    43   16.5   4:18 (233, 22)  
Apr. 10  23  9.17   42 38.3   6.628   5.953    44   16.5   4:07 (234, 25)  

* C/2017 Y2 ( PanSTARRS )

Now it is 16.7 mag (Mar. 14, Toshihiko Ikemura, Hirohisa Sato). It is observable at 16.5 mag from spring in 2020 to summer in 2021.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3  17 39.40  -13 22.0   4.379   4.783   107   16.5   4:18 (348, 41)  
Apr. 10  17 34.11  -13 50.0   4.272   4.797   116   16.5   4:07 (355, 41)  

* C/2019 O3 ( Palomar )

Now it is 16.2 mag (Mar. 16, Toshihiko Ikemura, Hirohisa Sato). It stays at 16-17 mag from 2020 to 2021. 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)  
Apr.  3  19 47.10   39 39.3   9.019   8.821    75   16.7   4:18 (249, 57)  
Apr. 10  19 47.41   40 41.3   8.965   8.822    78   16.7   4:07 (248, 61)  

* C/2020 O2 ( Amaral )

Now it is 17.0 mag (Mar. 4, D. Husar). It will brighten up to 16.5 mag in summer.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3  17 37.30  -32 10.1   4.599   4.996   107   16.8   4:18 (352, 22)  
Apr. 10  17 36.34  -31 27.6   4.479   4.984   114   16.7   4:07 (356, 23)  

* 398P/2020 P2 ( Boattini )

First return of a new periodic comet which brightened up to 13 mag in 2009. It brightened up to 11.7 mag in January (Jan. 10, Marco Goiato). Now it is fading. It has already faded down to 16.9 mag (Mar. 29, Thomas Lehmann). It stays observable in good condition while the comet will be fading after this.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3   8 15.57   27 45.5   1.104   1.688   106   16.8  19:48 ( 30, 82)  
Apr. 10   8 32.04   27 16.2   1.201   1.733   103   17.2  19:55 ( 48, 79)  

* P/2020 U2 ( PanSTARRS )

Brightened very rapidly up to 15.0 mag (Feb. 4, Michael Jager). Now it is fading. It hasl already faded down to 16.9 mag (Mar. 14, Toshihiko Ikemura, Hirohisa Sato). It is observable in good condition in the Northern Hemisphere. It locates low in the Southern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3   5 34.05   28  5.6   2.135   2.044    71   16.9  19:48 ( 93, 51)  
Apr. 10   5 50.66   27 53.0   2.227   2.071    67   17.1  19:55 ( 95, 48)  

* A/2019 U5

Now it is 17.0 mag (Apr. 1, Michael Jager). Although it is an asteroid, it is brightening rapidly. It may brighten up to 11 mag in 2023. In the Northern Hemisphere, it stays observable in good condition for a long time. It locates extremely low in the Southern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3  18 33.16   44 21.0   7.003   7.058    89   17.0   4:18 (235, 70)  
Apr. 10  18 30.53   45 17.2   6.907   7.013    91   16.9   4:07 (227, 73)  

* 413P/2020 W4 ( Larson )

First return of a new periodic comet which brightened up to 16 mag in 2014. Now it is 17.0 mag (Mar. 17, Toshihiko Ikemura, Hirohisa Sato). It stays observable at 17 mag in good condition until July.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3  12 33.91   12 41.1   1.319   2.290   161   17.0  23:45 (  0, 68)  
Apr. 10  12 27.33   12 14.3   1.317   2.272   156   16.9  23:11 (  0, 67)  

* C/2017 U7 ( PanSTARRS )

Now it is 17.7 mag (Mar. 6, ATLAS-MLO, Mauna Loa). It will be fading slowly.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3  18 24.40  -17  1.9   7.269   7.461    97   17.0   4:18 (336, 34)  
Apr. 10  18 22.04  -16 40.1   7.168   7.485   104   16.9   4:07 (341, 36)  

* C/2020 V2 ( ZTF )

Now it is 16.3 mag (Mar. 14, Toshihiko Ikemura, Hirohisa Sato). It is expected to brighten up to 10 mag in 2023. In the Northern Hemisphere, it stays observable in good condition until 2023 autumn. In the Southern Hemipshere, it stays extremely low until mid July, then it becomes unobservable for a while. But it becomes observable in good condition after 2023 summer.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3  12 45.04   37 19.1   6.837   7.604   137   17.0   0:01 (180, 88)  
Apr. 10  12 39.74   37 51.2   6.826   7.552   133   17.0  23:24 (180, 87)  

* C/2021 C3 ( Catalina )

Brightening rapidly. Now it is 17.0 mag (Mar. 24, F. Kugel, J.-G. Bosch). It stays 17 mag until April. 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)  
Apr.  3  11 17.24   29  6.4   1.492   2.343   139   17.4  22:28 (  0, 84)  
Apr. 10  10 57.29   33  4.5   1.612   2.362   127   17.5  21:41 (  0, 88)  

* C/2021 A1 ( Leonard )

Now it is 17.4 mag (Mar. 18, Toshihiko Ikemura, Hirohisa Sato). 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. 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)  
Apr.  3  12 44.39   60 48.7   3.621   4.129   113   17.5   0:01 (180, 64)  
Apr. 10  12 26.01   61 29.5   3.598   4.052   110   17.4  23:09 (180, 64)  

* 277P/LINEAR

It brightened rapidly and became brighter than expected. Now it is 16.9 mag (Mar. 18, Toshihiko Ikemura, Hirohisa Sato). It is observable in good 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)  
Apr.  3   5 26.34   19 42.0   2.211   2.073    68   17.4  19:48 ( 82, 46)  
Apr. 10   5 41.37   19 16.5   2.302   2.097    65   17.6  19:55 ( 85, 42)  

* 417P/2021 B1 ( NEOWISE )

First return of a new periodic comet observed at 19 mag in 2015. Now it is 17.8 mag (Mar. 4, Giuseppe Pappa). It will brighten up to 17 mag in early summer, and it will be observable in good condition.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3  17 54.29  -11 18.0   0.906   1.505   104   17.6   4:18 (343, 42)  
Apr. 10  18 11.90  -11 17.2   0.862   1.497   106   17.4   4:07 (343, 42)  

* C/2020 F7 ( Lemmon )

Now it is 17.1 mag (Mar. 18, Toshihiko Ikemura, Hirohisa Sato). It brightened rapidly. It stays 17-18 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 is observable only until May.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3   8 23.57   -7  3.4   5.101   5.586   114   17.5  19:48 (  5, 48)  
Apr. 10   8 20.62   -7  7.2   5.189   5.570   107   17.5  19:55 ( 18, 46)  

* C/2019 C1 ( ATLAS )

Now it is 17.8 mag (Mar. 16, Toshihiko Ikemura, Hirohisa Sato). Fading slowly. In 2021, it stays observable at 17-18 mag in good condition until early summer.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3  13  5.81  -17 36.7   5.965   6.942   166   17.5   0:22 (  0, 37)  
Apr. 10  13  3.80  -17  3.1   5.967   6.957   170   17.5  23:48 (  0, 38)  

* C/2020 R7 ( ATLAS )

Now it is 18.2 mag (Mar. 12, Thomas Lehmann). It is expected to brighten up to 12.5 mag in 2022. In the Southern Hemisphere, it stays observable in good condition for a long time. In the Northern Hemisphere, it is not observable until 2022 autumn.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3   2 51.01  -42 32.8   6.239   5.729    55   17.6  19:48 ( 52,-20)  
Apr. 10   2 54.13  -42 14.1   6.194   5.679    55   17.5  19:55 ( 55,-25)  

* 98P/Takamizawa

It has not been observed yet in this apparition. In the Southern Hemissphere, appearing in the morning sky. It is already fading.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3  22 40.36  -11 48.3   2.587   1.874    36   17.5   4:18 (283, -2)  
Apr. 10  22 56.38  -10 40.5   2.577   1.905    38   17.7   4:07 (282, -1)  

* 99P/Kowal 1

Now it is 17.4 mag (Mar. 14, Toshihiko Ikemura, Hirohisa Sato). It stays 17-18 mag for a long time from 2021 to 2023.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3  10 41.50   12 12.7   4.067   4.910   143   17.6  21:54 (  0, 67)  
Apr. 10  10 39.40   12 18.5   4.127   4.903   136   17.6  21:24 (  0, 67)  

* C/2020 F2 ( ATLAS )

Now it is 17.6 mag (Mar. 19, ATLAS-MLO, Mauna Loa). It stays observable at 17-18 mag for a long time until 2024.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3  15 21.47  -10 57.0   8.420   9.225   141   17.6   2:37 (  0, 44)  
Apr. 10  15 17.58  -10 31.6   8.337   9.214   149   17.6   2:06 (  0, 44)  

* C/2020 Y3 ( ATLAS )

Now it is 16.8 mag (Mar. 14, Toshihiko Ikemura, Hirohisa Sato). It will be fading after this.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3  14 39.98   39 52.0   1.710   2.457   128   17.8   1:56 (180, 85)  
Apr. 10  14 30.76   43 47.2   1.786   2.504   125   17.9   1:19 (180, 81)  

* C/2019 E3 ( ATLAS )

It stays 17-18 mag for a long time until 2026. In the Southern Hemisphere, it stays sobservable in good condition for a long time. It is not observable in the Northern Hemisphere. Now it is 19.7 mag (Mar. 13, A. C. Gilmore, P. M. Kilmartin), fainter than this ephemeris.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3   8 56.92  -56 19.2  11.087  11.493   111   17.8  20:09 (  0, -1)  
Apr. 10   8 53.96  -55 57.8  11.091  11.477   110   17.8  19:55 (  2, -1)  

* 162P/Siding Spring

Now it is 16.9 mag (Mar. 10, Toshihiko Ikemura, Hirohisa Sato). It will be fading after this, and will be fainter than 18 mag in April. In the Northern Hemisphere, it stays observable in good condition for a long time after this. In the Southern Hemisphere, it will never be unobservable after this.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3   4 22.47   44 48.2   2.063   1.805    61   17.8  19:48 (122, 42)  
Apr. 10   4 47.31   45 23.6   2.155   1.853    59   17.9  19:55 (123, 40)  

* 152P/Helin-Lawrence

Now it is 18.2 mag (Mar. 19, ATLAS-MLO, Mauna Loa). It will brighten up to 16 mag in 2022. In 2021, it stays observable at 18 mag until September.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3  13 49.30    2 42.7   2.473   3.441   162   17.9   1:05 (  0, 58)  
Apr. 10  13 45.13    3  7.4   2.443   3.426   166   17.8   0:34 (  0, 58)  

* 284P/McNaught

It will brighten up to 15 mag from summer to autumn, and it will be observable in good condition. It already locates high in the Southern Hemisphere. It will be getting higher gradually also in the Northern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3  21  8.76  -11 26.0   2.949   2.548    57   18.0   4:18 (297, 16)  
Apr. 10  21 20.34  -10 44.7   2.857   2.529    61   17.8   4:07 (297, 17)  

* C/2021 C4 ( ATLAS )

Now it is 17.5 mag (Mar. 15, Giuseppe Pappa). It is observable at 18 mag in spring. 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)  
Apr.  3  13 54.58  -39 13.7   3.710   4.547   142   17.9   1:11 (  0, 16)  
Apr. 10  13 43.17  -37 44.3   3.664   4.555   149   17.9   0:32 (  0, 17)  

* 141P/Machholz 2

It brightened very rapidly in early December, and it brightened up to 10.0 mag in January (Jan. 7, Michael Jager). Now it is fading. However, it brightened in outburst in early March up to 12.9 mag (Mar. 3, Martin Masek). Now it is 14.1 mag (Mar. 15, Thomas Lehmann).

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3   6 52.58    5 54.2   1.407   1.733    90   17.9  19:48 ( 45, 53)  
Apr. 10   7  9.25    6  7.6   1.537   1.805    87   18.6  19:55 ( 51, 50)  

* C/2020 K1 ( PanSTARRS )

Now it is 17.8 mag (Mar. 25, ATLAS-MLO, Mauna Loa). It is expected to brighten up to 12 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)  
Apr.  3  18 50.09   43  3.0   7.357   7.358    86   18.0   4:18 (241, 68)  
Apr. 10  18 49.86   43 35.8   7.259   7.310    88   17.9   4:07 (237, 71)  

* 47P/Ashbrook-Jackson

Now it is 17.7 mag (Mar. 7, ATLAS-MLO, Mauna Loa). Although it is around the aphelion, it is much brighter than originally predicted.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3  10 51.62   10 30.5   4.539   5.405   146   18.1  22:04 (  0, 65)  
Apr. 10  10 48.74   10 37.4   4.608   5.408   139   18.1  21:33 (  0, 66)  

* P/1999 J6 = P/2004 V9 = P/2010 H3 ( SOHO )

Marsden group's comet. Three apparitions of this comet was confirmed in 1999, 2004 and 2010. It approached to Sun down to 0.044 a.u. on Feb. 28. After the perihelion passage, it may be observed on the ground from March to April.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr.  3  21 11.17  -18  4.1   1.156   1.061    58   24.7   4:18 (301, 11)  
Apr. 10  21  5.14  -19 24.7   1.161   1.202    67   25.5   4:07 (306, 14)  

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