Weekly Information about Bright Comets (2012 Apr. 21: North)

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Updated on April 24, 2012
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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/2009 P1 ( Garradd )

Now it is 8.0 mag (Apr. 22, Salvador Aguirre). Fading slowly. In the Northern Hemisphere, it will be unobservable at 10 mag in June. In the Southern Hemisphere, it is observable in the evening low sky from April to June.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr. 21   8 54.40   43 29.4   1.943   2.221    92    8.3  20:07 (126, 74)  
Apr. 28   8 50.79   39 33.1   2.115   2.284    86    8.6  20:15 (109, 67)  

* (596) Scheila

Big asteroid discovered in 1906. It suddenly showed the cometary activity on Dec. 11, 2010, probably due to an impact of a small object. It was very bright as 11.5 mag visually (Dec. 17, 2010, Juan Jose Gonzalez). It has already turned to be stellar.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr. 21  17  0.98  -18 12.3   1.632   2.448   134   12.8   3:04 (  0, 37)  
Apr. 28  16 59.04  -18 44.6   1.572   2.447   142   12.6   2:35 (  0, 36)  

* C/2011 F1 ( LINEAR )

Already so bright as 11.6 mag and visible visually (Apr. 21, Carlos Labordena). It is expected to be bright as 9 mag from 2012 to 2013. In the Northern Hemisphere, it keeps observable in good condition for a long time until 2012 autumn when the comet brightens up to 10 mag. In the Southern Hemisphere, it is hardly observble before the perihelion passage. But it becomes observable in good condition since 2013 after the perihelion passage.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr. 21  15 16.83   56 41.6   3.114   3.576   109   13.0   1:20 (180, 68)  
Apr. 28  15  7.65   56 48.5   3.062   3.513   108   12.9   0:44 (180, 68)  

* 21P/Giacobini-Zinner

It brightened up to 9 mag in January and February in the evening low sky. In the Southern Hemisphere, it is observable in the evening extremely low sky in April and May. It will never be observable again in the Northern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr. 21   3 43.26    2  9.2   2.199   1.398    28   13.1  20:07 ( 95, -3)  
Apr. 28   4  6.61    2 28.7   2.265   1.458    28   13.5  20:15 ( 97, -6)  

* 78P/Gehrels 2

Now it is 12.2 mag (Mar. 25, Jakub Koukal). It is already low in the evening. It will be unobservable at the end of April.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr. 21   4 22.59   17 48.8   2.897   2.164    35   13.5  20:07 (103, 13)  
Apr. 28   4 38.48   18 19.0   2.961   2.186    32   13.6  20:15 (106, 10)  

* C/2006 S3 ( LONEOS )

Now it is bright as 13.4 mag (Mar. 27, Jakub Cerny). It keeps 13-14 mag and observable in good condition until September.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr. 21  17 44.59  -13 20.4   4.497   5.131   124   13.6   3:48 (  0, 42)  
Apr. 28  17 36.78  -13 13.4   4.394   5.132   132   13.5   3:13 (  0, 42)  

* C/2009 F4 ( McNaught )

Now it is bright as 12.8 mag and visible visually (Mar. 14, John Drummond). It keeps bright as 13-14 mag for a long time after this until 2013. It is not observable in the Northern Hemisphere, but it is observable in good condition in the Southern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr. 21   3 24.13  -59 34.3   5.714   5.516    73   13.6  20:07 ( 37,-35)  
Apr. 28   3 32.51  -58 23.9   5.716   5.524    73   13.6  20:15 ( 40,-38)  

* C/2011 UF305 ( LINEAR )

It brightened much faster than expected. It is so bright as 11.8 mag and visible visually (Apr. 22, Uwe Pilz). In the Northern Hemisphere, it keeps observable at 12-14 mag in good condition until early 2013. In the Southern Hemisphere, it is not observable until late 2012.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr. 21  21 12.79   63 47.4   2.524   2.393    70   13.7   3:50 (211, 48)  
Apr. 28  21 29.37   68 40.2   2.490   2.358    70   13.6   3:40 (204, 46)  

* 29P/Schwassmann-Wachmann 1

Now it is visible visually at 13.6 mag (Mar. 22, Carlos Labordena).

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr. 21  12 12.61  -11 39.5   5.335   6.258   154   13.6  22:13 (  0, 43)  
Apr. 28  12 10.26  -11 21.4   5.383   6.258   147   13.6  21:43 (  0, 44)  

* C/2011 Q2 ( McNaught )

Now it is very bright at 12.5 mag (Apr. 1, Michael Jager). In the Northern Hemisphere, it locates extremely low in the morning until June. It will be observable at high location after summer. 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. 21   1 11.13   33 28.9   2.762   1.888    23   13.7   3:50 (231,  4)  
Apr. 28   1 31.08   35 19.8   2.830   1.955    24   13.9   3:40 (230,  5)  

* C/2011 R1 ( McNaught )

Now it is 14.3 mag (Mar 13, Jakub Cerny). It is already unobservable in the Northern Hemisphere. In the Southern Hemisphere, it locates extremely low now. But it will be getting higher gradually after May. It is expected to be observable at 11-13 mag for a long time from 2012 summer to 2013 summer. It will be observable in excellent condition in the Southern Hemisphere. But it is not observable until 2013 January in the Northern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr. 21   1 53.92  -33  8.7   3.573   2.950    45   14.0   3:50 (285,-42)  
Apr. 28   2  1.52  -33 48.3   3.468   2.896    48   13.8   3:40 (287,-41)  

* C/2011 L4 ( PanSTARRS )

It is expected to be a great comet of -1 mag in 2013 spring. It is already bright and visible visually at 14.3 mag (Mar. 30, Alan Hale). Brightening faster than originally expected. In 2012, it keeps observable until summer while brightening gradually. It locates somewhat low in the Northern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr. 21  16 48.78  -25 16.6   4.114   4.898   137   14.0   2:52 (  0, 30)  
Apr. 28  16 43.58  -25 28.1   3.964   4.823   145   13.8   2:20 (  0, 30)  

* (3200) Phaethon

It will pass the perihelion on May 2. But it is not observable when it becomes bright at this apparition.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr. 21   3 22.10   14 48.0   1.163   0.427    21   14.9  20:07 (108,  0)  
Apr. 28   3 15.33   13 22.6   0.963   0.225    12   14.4  20:15 (114,-10)  

* C/2010 S1 ( LINEAR )

Now it is visible visually at 13.9 mag (Mar. 26, Jakub Cerny). It is expected to be 13 mag and will be observable in good condition in 2013. In the Northern Hemisphere, it will be getting higher gradually in the morning sky, and keeps observable 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. 21  23 26.74   49 56.4   7.135   6.518    48   14.5   3:50 (227, 29)  
Apr. 28  23 27.99   50 25.1   7.091   6.497    50   14.4   3:40 (228, 32)  

* C/2011 A3 ( Gibbs )

Although it has been unobservable for a while, now it is appearing in the morning sky. Now it is 14.3 mag (Mar. 27, Jakub Cerny). After this, it will be observable in good condition in the Southern Hemisphere while fading gradually. It will locate somewhat low in the Northern Hemisphere. In 2011, some visual observers reported it was very bright as 10-12 mag.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr. 21  22  6.95  -13 54.0   3.051   2.733    62   14.5   3:50 (296, 11)  
Apr. 28  22 17.02  -13 53.2   3.009   2.773    66   14.5   3:40 (297, 13)  

* 71P/Clark

It brightened up to 17.1 mag in late June in 2011 (June 24, J. F. Hernandez). The condition of this apparition is bad, and it was not observable around the perihelion passage. It is appearing in the morning sky in the Southern Hemisphere, but it locates extremely low. It will not be observable until June in the Northern Hemisphere, when the comet will be 15.5 mag.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr. 21  23 47.63   -8 56.0   2.652   1.961    38   14.5   3:50 (277, -5)  
Apr. 28   0  1.48   -7 33.6   2.643   1.998    41   14.6   3:40 (277, -4)  

* 246P/2010 V2 ( NEAT )

Now it is so bright as 12.3 mag and visible visually (Mar. 22, Carlos Labordena). Although it was extremely faint as 20.5 mag at the recovery in 2010 autumn, it brightened rapidly. It will keep 12-14 mag and observable in good condition for a long time from 2012 to 2013. But it locates somewhat low in the Northern Hemisphere in 2013.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr. 21  13  6.93   14 40.1   2.320   3.234   150   14.7  23:06 (  0, 70)  
Apr. 28  13  2.33   14 35.2   2.341   3.219   145   14.7  22:34 (  0, 70)  

* 58P/Jackson-Neujmin

This comet brightened up to 10 mag in outburst in 1995, however, it became lost after that. The condition of this apparition is bad. It is not observable around the perihelion passage. Maybe it can be recovered after summer when it appears in the morning sky.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr. 21   1 13.66    3 39.0   2.339   1.381    13   15.4   3:50 (254,-15)  
Apr. 28   1 36.77    5 14.5   2.344   1.391    14   15.1   3:40 (252,-15)  

* C/2010 G2 ( Hill )

It reached up to 9.7 mag with a large bright coma in last autumn (Oct. 29, Juan Jose Gonzalez). Now it is fading. It has already faded down to 14.6 mag (Mar. 21, Jakub Cerny). It is already unobservable in the Northern Hemisphere. It will be unobservable in late April in the Southern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr. 21   3 39.03   -9  3.7   4.102   3.306    33   15.4  20:07 ( 86,-11)  
Apr. 28   3 44.98   -9 30.3   4.183   3.364    31   15.5  20:15 ( 90,-17)  

* C/2011 O1 ( LINEAR )

Now it is 16.0 mag (Mar. 26, Jakub Cerny). In the Southern Hemisphere, it will be observable at 15-16 mag in good condition for a long time until 2013 summer. It is not observable at all in the Northern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr. 21  20 21.69  -52 41.1   3.803   4.027    95   15.4   3:50 (338, -4)  
Apr. 28  20 27.63  -54 40.4   3.700   4.011   100   15.4   3:40 (340, -5)  

* C/2012 CH17 ( MOSS )

Now it is 17.3 mag (Apr. 14, Yasukazu Ikari). It will brighten up to 13.5 mag from summer to autumn. It keeps observable for a long time until December. In the Northern Hemisphere, it locates high until spring. But after that, it keeps locating low in the evening. In the Southern Henmisphere, it keeps locating low all through the time.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr. 21  10 51.07   36 31.3   1.986   2.576   114   16.6  20:51 (180, 89)  
Apr. 28  10 48.74   36 32.5   1.991   2.501   108   16.5  20:21 (180, 89)  

* 60P/Tsuchinshan 2

Now it is 17.6 mag (Mar. 13, Toshiyuki Takahashi). It brightened rapidly as expected. It will reach up to 16.5 mag from spring to summer. However, it locates extremely low in the Southern Hemisphere. In the Northern Hemisphere, it is getting lower gradually in the evening sky, and will be unobservable in June.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr. 21   5 26.07   22  5.4   2.067   1.633    51   16.7  20:07 ( 98, 29)  
Apr. 28   5 46.78   22  7.6   2.097   1.625    49   16.6  20:15 (100, 26)  

* C/2011 J2 ( LINEAR )

Now it is 16.9 mag (Apr. 14, Yasukazu Ikari). It is expected to keep 13 mag and observable in good condition in the Northern Hemisphere for a long time from 2013 to 2014. It keeps observable at 17-18 mag in good condition until June.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr. 21  10 32.57    9 37.9   5.685   6.317   125   16.8  20:33 (  0, 65)  
Apr. 28  10 29.52   10 22.3   5.745   6.271   117   16.8  20:15 (  8, 65)  

* C/2010 R1 ( LINEAR )

Now it is 16.7 mag (Apr. 14, Yasukazu Ikari). It keeps observable at 17 mag for a long time from 2011 to 2013. In 2012, it keeps observable in good condition until early September.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr. 21  15 53.89    5 48.0   4.766   5.625   145   16.9   1:58 (  0, 61)  
Apr. 28  15 45.33    6 25.5   4.722   5.623   150   16.9   1:22 (  0, 61)  

* C/2012 A2 ( LINEAR )

Now it is 16.7 mag (Apr. 21, Catalina Sky Survey). In the Northern Hemisphere, it keeps observable at 16-17 mag in good condition for a long time from 2012 to 2013. It is not observable in the Southern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr. 21   9 43.50   65 57.5   3.843   3.965    89   16.9  20:07 (175, 59)  
Apr. 28   9 29.45   65 36.7   3.916   3.937    83   16.9  20:15 (166, 58)  

* 96P/Machholz 1

Now it is 18.2 mag (Apr. 20, Pierre Auger Observatory). It will brighten rapidly after this. It will approach to the sun down to 0.12 A.U. on July 14. In the Southern Hemisphere, it keeps observable in good condition except for mid July only, in the morning sky before the perihelion passage, and in the evening sky after the perihelion passage. In the Northern Hemisphere, it is not observable before the perihelion passage. But it will appear in the evening sky at 8 mag in late July. Then it keeps observable while fading rapidly in the evening low sky.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr. 21  23  6.07  -37 44.1   2.066   1.852    63   17.5   3:50 (307,-14)  
Apr. 28  23 27.30  -37 25.3   1.900   1.751    65   17.0   3:40 (306,-14)  

* 105P/Singer Brewster

It has not been observed since 2011 March. But it must be already bright as 17.5 mag. It will brighten up to 17 mag and will be observable in good condition from spring to summer.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr. 21  19 14.81  -11 19.2   1.636   2.093   102   17.3   3:50 (332, 39)  
Apr. 28  19 21.95  -10 23.8   1.577   2.105   107   17.2   3:40 (334, 41)  

* 152P/Helin-Lawrence

Now it is 17.5 mag (Apr. 19, C. Bell). It tends to brighten after the perihelion passage. It keeps observable at 17 mag from 2012 to 2013. It locates somewhat low in the Northern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr. 21  16 46.36  -15 10.2   2.322   3.146   138   17.3   2:50 (  0, 40)  
Apr. 28  16 44.44  -15 12.5   2.258   3.141   145   17.3   2:20 (  0, 40)  

* 49P/Arend-Rigaux

It reached up to 11-12 mag in 2011 autumn. Now it is fading. It has already faded down to 17.0 mag (Apr. 15, A. Diepvens). It keeps observable in good condition until May when it becomes fainter than 18 mag. It locates somewhat low in the Southern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr. 21  11 46.59   29 58.0   1.594   2.349   127   17.4  21:47 (  0, 85)  
Apr. 28  11 46.07   29  7.0   1.699   2.397   122   17.6  21:19 (  0, 84)  

* C/2005 L3 ( McNaught )

It brightened up to 13-14 mag and became visible visually from 2007 to 2009. Now it is fading. But it is still bright as 16.9 mag (Mar. 19, V. Gerke, S. Plaksa, A. Novichonok). In the Northern Hemisphere, it keeps observable in excellent condition until early summer in 2012. In the Southern Hemisphere, it locates extremely low only.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr. 21   9 53.24   39 58.7  11.461  11.738   103   17.4  20:07 (152, 84)  
Apr. 28   9 51.35   39 44.9  11.604  11.774    97   17.5  20:15 (119, 79)  

* 117P/Helin-Roman-Alu 1

Now it is 16.4 mag (Apr. 15, J. F. Hernandez). It will brighten up to 13 mag in 2014. In 2012, it is observable at 17 mag in good condition in spring.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr. 21  10 54.93   17 27.1   3.569   4.245   126   17.5  20:55 (  0, 72)  
Apr. 28  10 53.49   17 17.9   3.641   4.230   119   17.6  20:26 (  0, 72)  

* C/2012 BJ98

Brightening faster than expected. Now it is 17.5 mag (Apr. 12, Michael Jager). It will be getting lower in the evening after this. It keeps observable at 17 mag until mid June in the Northern Hemisphere, or until mid July in the Southern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr. 21   8  8.18   21  2.5   2.534   2.702    88   17.9  20:07 ( 69, 61)  
Apr. 28   8 15.19   20 44.4   2.580   2.660    83   17.8  20:15 ( 76, 55)  

* 240P/2010 P1 ( NEAT )

It had been fading after the perihelion passage in 2010 October, but it brightened again in outburst on Apr. 5, 2011. It reached up to 14.7 mag in May (May 28, Hidetaka Sato). It is bright as 17.5 mag still now, much brighter than expected (Apr. 16, Catalina Sky Survey). It locates low in the Southern Hemisphere. But in the Northern Hemisphere, it keeps observable in good condition after this. It will keep 18 mag for a while.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
Apr. 21  13 10.95   21 42.6   3.268   4.129   144   18.0  23:10 (  0, 77)  
Apr. 28  13  6.25   21 34.6   3.335   4.154   139   18.1  22:38 (  0, 76)  

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