Weekly Information about Bright Comets (2005 July 30: South)

Japanese version
Home page
Updated on August 3, 2005
Last week North Next week

Best time and the azimuth, altitude (A,h) are at lat. 35 deg in the Southern Hemisphere.

---------------------------------------------------------------------

* 21P/Giacobini-Zinner

Although it was faint as 15.2 mag on Mar. 14 (Yuji Ohshima), it brightened in April, and finally it became bright enough to be visible visually, 12.3 mag on May 2 (Juan Jose Gonzalez). Then comet kept brightening and reached to 9.2 mag (July 2, Carlos Labordena). Although it became brightest about 2 weeks before the perihelion passage in its last appearance in 1998, it kept brightening until the perihelion passage in this return. Now it is brighter than original prediction by 1 mag, 9.9 mag (July 28, Seiichi Yoshida), however very low in the morning. The altitude keeps lower than 20 deg until late August. It will be higher than 30 deg after October, when it will be already fainter than 13 mag. It will pass only 0.5 degree by P/2005 JQ5 on Aug. 2.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
July 30   5 18.71   13 51.1   1.496   1.106    47   10.4   5:29 (233, 22)  
Aug.  6   5 43.85   11 25.1   1.521   1.143    48   10.7   5:23 (235, 23)  

* 9P/Tempel 1

The Deep Impact mission succeeded on July 4. It had kept bright at 10 mag for two months since May until the impact, while getting diffused gradually. The central nucleus shining just after the impact was observed even on the ground. Mike Linnolt confirmed that the degree of condensation (DC) increased from 4 to 8 during 30 minutes. But the total magnitude brightened by only 0.5 mag. The nuclear magnitude brightened by 1-2 mag. The change was temporary. The comet almost returned to be the original state on the next day. Because the influence to the comet was very small, it will be fading as predicted. It will be fainter than 12 mag in September. The condition keeps good in the Southern Hemisphere. However, it will be lower than 20 degree in mid August in the Northern Hemisphere. Only a few observations have been reported after the Deep Impact. But it was bright as 10.5 mag still on July 28 (Seiichi Yoshida).

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
July 30  14 33.43  -19 10.6   1.052   1.526    95   10.7  18:44 (147, 72)  
Aug.  6  14 51.20  -21 28.8   1.103   1.539    93   10.9  18:48 (134, 72)  

* 161P/2004 V2 ( Hartley-IRAS )

It was 14 mag on May 12 when appearing in the morning low sky (Michael Mattiazzo). Then it has been brightening as expected, and it was 11.3 mag in mid June around the perihelion passage (June 16, Juan Jose Gonzalez). In its last appearance, the comet unexpectedly brightened after the perihelion passage, and reached to the maximum brightness about 45 days after the perihelion passage. In this return, it continued brightening even after the perihelion passage again, and reached to 10.2 mag on July 2 (Juan Jose Gonzalez). However, then it turned to be fading. Now it is 11.6 mag (July 29, Juan Jose Gonzalez). The unexpected brightening in its last appearance seems to be an exceptional outburst. It is diffused visually. In the Northern Hemisphere, it keeps observable for a long time after this. Now it is observable all night, however, the altitude in the morning will be lower than 15 degree in early August. In the Southern Hemisphere, it is not observable until it becomes faint.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
July 30  11 12.88   75  0.5   1.575   1.385    60   11.1  18:44 (165,-26)  
Aug.  6  12  6.08   68  9.9   1.654   1.424    58   11.4  18:48 (161,-21)  

* C/2005 K2 ( LINEAR )

It brightened rapidly in early June, and reached to 8.9 mag on June 10 (Juan Jose Gonzalez). Then it stopped at 9 mag, and became unobseravble in late June in the Northern Hemisphere. It was visible still on July 4 (Michael Mattiazzo), however, it faded rapidly down to 12 mag, or fainter, on July 10 (Terry Lovejoy). Because it passed only 0.54 AU from the sun at the perihelion passage on July 5, it could vanish. It is appearing in the morning sky in the Southern Hemisphere. It is not observable until September in the Northern Hemisphere. Nucleus split was found on June 12 by many persons including Giovanni Sostero. The secondary component had been visible until June 22, however, became invisible on June 23 (Ernesto Guido, Giovanni Sostero).

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
July 30   7 42.64  -10 43.2   1.416   0.776    32   11.5   5:29 (277,  9)  
Aug.  6   7 33.75  -11 20.9   1.478   0.886    35   12.1   5:23 (273, 16)  

* P/2005 JQ5 ( Catalina )

New periodic comet with a very short period of 4.4 years. It passed very close by the earth in June, about 0.1 AU. Although it was so faint as 17.5 mag in early May, it brightened rapidly, 13.5 mag on June 6, 12.0-12.5 mag on June 12 (Michael Jager), and became visible visually as bright as 10.3 mag on June 25 (Juan Jose Gonzalez). Because it was so close to the earth, it had a very large and faint coma with a diameter of 4-8 arcmin. Surprisingly, it was detected on survey images on June 24 as a very bright and large object, 8-9 mag with a diameter of 20 arcmin (Terry Lovejoy). It is appearing again in the morning sky. It was not visible, fainter than 9.5 mag on July 28 (Seiichi Yoshida). But Michael Jager observed it on Aug. 2 and found P/2005 JQ5 was bright as around 11.5 mag still now, as bright as this ephemeris. However, because it is still close to the earth, 0.3 AU, it is very large and diffused. Therefore, it will be hard to see visually, or take an image using a CCD camera, without clear sky. It will pass only 0.5 degree by 21P on Aug. 2.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
July 30   5 31.13   12 17.3   0.310   0.826    45   11.6   5:29 (237, 21)  
Aug.  6   5 29.52   12 22.8   0.374   0.838    51   12.1   5:23 (232, 25)  

* C/2005 A1 ( LINEAR )

In January when it was visible in the Northern Hemisphere, it was an 11 mag small object. However, after it has gone to the southern sky, it brightened rapidly and reached to 8.0 mag from March to April (Mar. 4 and Apr. 7, Alexandre Amorim). After the perihelion passage on Apr. 10, it turned to be fading slowly, 8.9 mag on May 12 (Michael Mattiazzo) and 10-10.5 mag on May 31 (Terry Lovejoy). It is bright as 11.4 mag still now (July 28, Seiichi Yoshida). In the Northern Hesmisphere. It keeps observable in good condition while fading gradually. The split of the nucleus was found on June 25. The secondary nucleus was fainter than the primary by 0.7 mag, so both nucleus can be detected on CCD images. No effect of the split was found on the total brightness of the comet.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
July 30   1 29.53   19 30.3   1.597   2.019    98   11.6   4:59 (180, 36)  
Aug.  6   1 17.36   22  0.1   1.576   2.108   106   11.7   4:20 (180, 33)  

* C/2005 N1 ( Juels-Holvorcem )

New comet. Although it is 14 mag by CCD observations, it is bright as 12.4 mag visually (July 8, Juan Jose Gonzalez). It keeps 12 mag until September. Because it moves in the northern sky, it is not observable in the Southern Hemisphere until when it becomes faint. In the Northern Hemisphere, it keeps locating very low in the morning sky. It will not be high until when it becomes faint. It was reported as bright as 11.0 mag on July 28 (Seiichi Yoshida), so maybe it is brightening.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
July 30   5 48.65   50 39.0   1.635   1.186    46   11.8   5:29 (213, -9)  
Aug.  6   6 43.65   52 23.5   1.622   1.155    45   11.7   5:23 (215,-14)  

* C/2004 Q2 ( Machholz )

It was fantastic, so bright as 3.5 mag, so large as 30 arcmin, locating high overhead at its best time in early January. Then it has been getting fainter and smaller gradually, and 11.9 mag on July 29 (Carlos Labordena). The diameter is small now, about 2-2.5 arcmin, and very diffused. In the Northern Hemisphere, it keeps observable in good condition for a long time while the comet is bright enough visible visually until October when it becomes faint as 14 mag.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
July 30  13 46.71   22 47.4   3.014   2.862    71   12.0  18:44 (157, 29)  
Aug.  6  13 54.40   20 44.5   3.159   2.939    68   12.2  18:48 (150, 28)  

* C/2003 T4 ( LINEAR )

The brightness evolution had been slower than a typical comet since its discovery until the perihelion passage in early April. Although it kept bright as 8 mag from mid March to early May, it seems to start fading in mid May as expected, 8.4 mag on May 12 (Michael Mattiazzo). After this, it is not observable in the Northern Hemisphere until late September when it appears very low sky at dawn as 14 mag. It had been low until early July even in the Southern Hemisphere. Probably, the comet has faded out rapidly down to 12 mag while locating low. However, no observations have been reported since mid May, so it is uncertain how the comet is fading now. Unusually strong non-gravitational parameters are revealed by the orbital calculation, but the reason has not been revealed yet.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
July 30   6 58.82  -33 33.1   2.483   2.112    57   12.2   5:29 (292, 30)  
Aug.  6   7  7.27  -33 49.9   2.570   2.202    57   12.4   5:23 (291, 32)  

* 37P/Forbes

Although it was only 19 mag in January, it brightened as expected, and became visible visually at 12.5 mag on June 7 (John Drummond). Now it is 11.7 mag (July 1, Nicolas Biver). It will be visible as bright as 12 mag until September. In the previous return, it was 1.5 mag brighter than this ephemeris visually. So it can be around 11.0 mag visually at best in this return, too. The condition is good in the Southern Hemisphere. However, it keeps locating very low in the Northern Hemisphere. It is September when it becomes higher than 30 deg.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
July 30  16 27.61  -31 40.5   0.771   1.573   122   12.4  19:56 (180, 87)  
Aug.  6  16 41.57  -30 31.3   0.806   1.573   119   12.5  19:42 (180, 85)  

* C/2004 B1 ( LINEAR )

It will reach to 9 mag in 2006 spring. It had been brightening well as expected until 2005 March. It was 15.1 mag on Mar. 5 (Mitsunori Tsumura). Then it had been too low for a while, however, now it locates high again in the Southern Hemisphere. However, no observations have been reported since mid March, so the current brightness is uncertain. In the Southern Hemisphere, it keeps observable for a long time after this. In the Northern Hemisphere, it is not observable until 2006 March, except it appears very low in the morning at 12 mag from late August to early September. After 2006 March, northern people can observe it for a long time while it is getting fainter.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
July 30   5 29.53  -24  4.8   3.252   2.925    62   12.7   5:29 (271, 44)  
Aug.  6   5 35.55  -26 12.6   3.109   2.858    66   12.5   5:23 (272, 48)  

* C/2005 E2 ( McNaught )

It was 16.4 mag at the discovery in March (Mar. 12, R. H. McNaught), but it brightened up to 14.4 mag on June 6 (Yuji Ohshima). It is expected to be bright as 10 mag in early 2006. In the Southern Hemisphere, it keeps locating high until November while the comet is getting brighter gradually. In the Northern Hemisphere, it keeps locating very low around 15 deg high until September. So, it may be too hard to see visually for a long time.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
July 30  20  1.83  -40  6.0   2.110   3.071   157   12.9  23:28 (  0, 85)  
Aug.  6  19 54.06  -39 59.1   2.067   3.002   152   12.8  22:53 (  0, 85)  

* 29P/Schwassmann-Wachmann 1

It had been always brighter than 13 mag and visible visually all through the season in 2004. In 2005, it is observable in very good condition, almost overhead in the Northern Hemisphere from summer to winter. However, it seems inactive now in 2005. Ater observed as 14.2 mag on May 31 (Ken-ichi Kadota), the nuclear magnitude was so faint as 16 mag in June. It was bright and large, 12.8 mag with a diameter of 2.5 arcmin without central condensation on June 29 (Jiri Srba). However, it was not visible, fainter than 13.3 mag, on July 15 (Reinder J. Bouma).

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
July 30   2 17.52   23 30.8   5.716   5.752    86   13.5   5:29 (185, 31)  
Aug.  6   2 19.28   23 52.0   5.609   5.753    93   13.4   5:21 (180, 31)  

* C/2003 K4 ( LINEAR )

It was bright as 7.5 mag in early January, easy to see with binoculars. However, it faded and got diffused rapidly in the evening sky after that. It faded to 10.7 mag on Mar. 15 visually (Alexandre Amorim), and 11.5 mag on Apr. 4 by CCD observation (Mitsunori Tsumura), then it became unobservable. It has been already appearing at dawn since mid June in the Southern Hemisphere, but no observations have been reported. It is appearing in the morning also in the Northern Hemisphere. It may be brighter than 14 mag and visible visually.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
July 30   4 32.23   -4 44.6   4.366   4.036    64   13.7   5:29 (238, 43)  
Aug.  6   4 32.37   -5  8.2   4.333   4.109    70   13.7   5:23 (233, 48)  

* C/2003 WT42 ( LINEAR )

It brightened from 18 to 15 mag during one year from the end of 2003 to early 2005. The brightness evolution was much faster than that of a typical comet. After that, it kept 15-15.5 mag until May. Although it had been too low for a while, it will be getting higher again in August. It can be 13 mag and may be visible visually in next winter.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
July 30   7 53.60   45  7.8   6.408   5.533    28   14.7   5:29 (230,-23)  
Aug.  6   8  2.97   45  2.6   6.359   5.515    31   14.7   5:23 (229,-21)  

* P/2004 F3 ( NEAT )

New bright periodic comet discovered in 2004 spring. It had been bright at 15.0-15.5 mag from spring to summer in 2004. The ephemeris says it keeps brighter than 19 mag even around the aphelion, however, the comet had not been discovered before 2004. This suggested the comet became bright temporarily last year. But actually, it keeps the same brightness in 2005, too. Now it is 14.8 mag (May 15, Akimasa Nakamura). It will be bright at 14.5 mag until autumn. However, it locates very low, around 20 deg high, in the Northern Hemisphere. So it will be hard to see it visually.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
July 30  20  3.95  -36 18.0   2.091   3.068   160   15.0  23:30 (  0, 89)  
Aug.  6  19 58.87  -36 43.5   2.130   3.081   155   15.0  22:58 (  0, 88)  

* 117P/Helin-Roman-Alu 1

Although it was faint as 16.4 mag in January, it brightened to 14.6 mag in May when it became at opposition (Jan. 26 and May 31, Ken-ichi Kadota). It was also visible visually as 14.3 mag (May 7, Juan Jose Gonzalez). Then it was predicted to be slightly fainter, however, it brightened furthermore visually, 13.8 mag on July 10 (Reinder J. Bouma). It is already declining in the evening sky, but it will be visible around 13.5-14 mag, brighter than this ephemeris by 1 mag. But on the other hand, the CCD nuclear magnitude has been reported fainter, 15.5 mag in July.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
July 30  15 24.12  -21  3.2   2.664   3.118   107   15.0  18:52 (180, 76)  
Aug.  6  15 27.49  -21 24.8   2.749   3.111   101   15.1  18:48 (160, 76)  

* 10P/Tempel 2

It is getting higher in the morning sky, however, it will be fading after this. It was 13.6 mag on May 12, as bright as expected (Michael Mattiazzo).

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
July 30   4 24.20   11 12.1   2.434   2.139    61   15.1   5:29 (223, 32)  
Aug.  6   4 34.80   11 22.0   2.403   2.183    65   15.2   5:23 (220, 34)  

* C/2005 K1 ( Skiff )

Although the CCD nuclear magnitude was reported so faint as 16.5-17 mag, it is actually bright as 15.7 mag (June 26, Giovanni Sostero). Sharply and strongly condensed with a narrow long tail. It will be 15 mag both in 2005 summer and 2006 summer. It moves southwards, so the condition in the Northern Hemisphere is better in 2005. It was visible visually as 13.8 mag (July 28, Seiichi Yoshida).

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
July 30  16 28.12   50 36.5   3.660   3.831    91   15.2  19:55 (180,  5)  
Aug.  6  16 27.08   48  4.3   3.666   3.815    90   15.1  19:26 (180,  7)  

* 32P/Comas Sola

It kept 12.5-13.0 mag since November, and it was visible visually as 12.7 mag still on May 4 (Seiichi Yoshida). However, it is not observable after this in this return.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
July 30  10 19.65   20  4.0   3.032   2.147    24   15.2  18:44 (115,  1)  
Aug.  6  10 34.93   18 31.0   3.090   2.180    21   15.4  18:48 (112, -1)  

* C/2004 L2 ( LINEAR )

It keeps 15.5 mag for a long time until 2006 January. Good condition in the Southern Hemisphere, but not observable in the Northern Hemisphere. It will be observable also in the Northern Hemisphere after 2006 August, when it is already faint as 16.5-17 mag. It moves through the Small Magellanic Could in August, so it may be hard to observe.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
July 30   0 39.57  -68  4.2   3.316   3.897   117   15.3   4:09 (  0, 57)  
Aug.  6   0 45.52  -69 34.4   3.310   3.882   117   15.3   3:47 (  0, 56)  

* P/2005 K3 ( McNaught )

Moving northwards, and now it locates high also in the Northern Hemisphere. It will be observable in good condition at 15.5 mag from July to November. Maybe it will be visible visually.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
July 30   2 31.01   17 29.1   1.200   1.515    85   15.4   5:29 (189, 37)  
Aug.  6   2 48.00   20 34.2   1.158   1.510    87   15.3   5:23 (187, 34)  

* C/2004 Q1 ( Tucker )

Although it had been rather large, well condensed, and easy to see until February, it became diffused in March. It was bright visually, 12.8 mag still on May 4 (Seiichi Yoshida). The fading after the perihelion passage is slow, and it will keep visible at 14 mag for a while after this. However, no visual observations have been reported since mid May. In the Northern Hemisphere, it is getting lower slowly in the evening sky.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
July 30  10 45.91   51 59.5   4.043   3.357    41   15.4  18:44 (144,-15)  
Aug.  6  10 58.85   50 17.9   4.119   3.414    40   15.6  18:48 (141,-16)  

* C/2004 K1 ( Catalina )

Although it was faint as 16.5 mag in early February, it was observed visually at 15.0 mag in May when it became at opposition (May 7, Shigeki Murakami). Then it was predicted to be slightly fainter, however, it actually brightened furthermore by 1 mag, 14.1 mag on June 13 by CCD observation (Yusuke Ezaki). It was 14.3 mag visually on July 10 (Edwin van Dijk). It is already declining in the evening sky, but it will be visible around 14.5 mag, brighter than this ephemeris by 1 mag. But on the other hand, the CCD nuclear magnitude has been reported fainter on and on, 16 mag in June and 16.5 mag in July.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
July 30  14  3.88   14  7.3   3.473   3.407    77   15.5  18:44 (157, 38)  
Aug.  6  13 59.18   13 22.6   3.607   3.412    70   15.6  18:48 (147, 35)  

* C/2005 B1 ( Christensen )

Recovery of a peculiar asteroid 2004 FS101 discovered in 2004 spring. Although it was 18 mag in mid January, it brightened to 16-16.5 mag in mid May. The brightness evolution was rather faster than that of a typical comet. It will be 14.5 mag around 2006 January, although it will be rather low for the northern observers. It keeps observable at 15-16 mag for a long time from 2005 spring to the end of 2006. Because it moves in the northern sky, it keeps observable for a long time in the Northern Hemisphere.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
July 30  13 16.09   48 30.6   4.117   3.765    62   15.9  18:44 (161,  2)  
Aug.  6  13 20.21   48 10.8   4.127   3.731    60   15.8  18:48 (156,  1)  

* 101P/Chernykh

It was observed as 17.0 mag on July 10, as bright as expected. It will be 15.5 mag from September to December. It is already high in the morning sky.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
July 30   0 25.92   -1 34.1   1.992   2.666   121   16.6   3:56 (180, 57)  
Aug.  6   0 29.03   -1 36.6   1.897   2.639   127   16.4   3:31 (180, 57)  

* C/2001 Q4 ( NEAT )

Although it had been locating low for a while, now it is getting higher again. Fading slowly, and still bright as 16 mag.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
July 30   2  6.86   62 14.8   5.703   5.565    77   17.0   5:29 (181, -7)  
Aug.  6   2  4.92   62 47.0   5.687   5.631    81   17.0   5:07 (180, -8)  

* C/2005 N5 ( Catalina )

New comet. It will be 17 mag in September.

Date(TT)  R.A. (2000) Decl.   Delta     r    Elong.  m1   Best Time(A, h)  
July 30   1 41.68    3 27.4   1.135   1.672   101   17.5   5:11 (180, 51)  
Aug.  6   2  1.39    2 24.2   1.084   1.657   104   17.4   5:03 (180, 53)  

---------------------------------------------------------------------

Copyright(C) Seiichi Yoshida (comet@aerith.net). All rights reserved.