GREAT COMETS IN HISTORY --------------------- John Pazmino NYSkiesAstronomy Inc nyskies.@nyskies.org www.nyskies.org 1998 March 17
[This article is reprinted from a webapge once maintained by Alan Chamberlin of JPL. He wrote it on 1996 October 2 after the flyover of comet Hyakutake in early 1996. This was so spectacular a comet that he compiled this table of 'great comets'. He revised it to include comet hale-Bopp. Since 1998, thru mid 2011, there were several bright comets, like Ikeya-Zhang, but none attained the rank of 'great comet'. The issue date is Chamberlin's latest revision. I made some trivial adjustments to the original layout.]
= = = = = Written: 1996 October 2 Modified: 1998 March 17 17:19 by: Alan B. Chamberlin for: Solar System Dynamics Group Jet Propulsion Laboratory
Great Comets in History --------------------- Donald K. Yeomans Jet Propulsion Laboratory/California Institute of Technology
A relative few comets are so visually impressive as to be termed "great comets". Just the right set of circumstances must occur. Far from the sun, the solid portions of comets, which consist mostly of water ice and embedded dust particles, are inactive. They are not large enough to be seen with the naked eye. However, when near the sun, the icy cometary surfaces vaporize and throw off large quantities of gas and dust thus forming the enormous atmosphere and tails that make comets so visually striking. It is the fluorescing of these gases, and particularly the reflection of sunlight from the minute dust particles in the comet's atmosphere and tail, that can make these objects so visually impressive. However, this activity by itself does not insure that a comet will become a great comet. An active comet can only become great by making a particularly close approach to the sun so that it produces enormous quantities of gas and dust or by making a close approach to the Earth so that it's tail can be easily viewed. In either case, great comets must be seen in a dark sky. While applying the appellation "great comet" to a particular cometary return is a subjective process, the following Table is an attempt to list the great naked-eye comets that have been reported. With the single exception of periodic comet Halley, all the tabulated comets have passed through the inner solar system either for the first time or the intervals between their returns are measured in thousands or millions of years. The first tabular entry gives the approximate date when the comet was first reported as a naked-eye object. The following column gives the approximate observational interval (in days) during which the comet remained a naked eye object. The next two columns give the date and distance in astronomical units when the comet reached its closest point to the sun (perihelion). One astronomical unit is the mean distance between the sun and Earth. The following columns give the date and distance when the comet reached its closest point to the Earth (perigee), and the date and apparent magnitude when the comet reached its brightest in a dark sky. A diffuse cometary image becomes noticeable to the naked eye when it reaches a magnitude of approximately 3.4 in a dark sky. Compared to a comet whose magnitude is 4, a 3rd magnitude comet would appear 2.5 times brighter and a magnitude 2 comet would appear 2.5 x 2.5 = 6.3 times brighter still, etc. The brightest star in the sky (Sirius) has an apparent magnitude of -1.5. At its brightest, the planet Jupiter appears at magnitude - 2.7.
1st Date Obs Perihelion Perigee Brightness Max. Reported Int Date Dist Date Dist Date Mag YYYY/mmm/DD (d) YYYY/mmm/DD (AU) YYYY/mmm/DD (AU) YYYY/mmm/DD ----------- --- ----------------- ---------------- ----------- - Name, Notes ----------------------------------- Julian Calendar --------------- B.C. dates ---------- 373-372 Winter < 1> 87/Jul 35 87/Aug/06 0.59 87/Jul/27 0.44 87/Jul/27 2 1P/Halley 12/Aug/25 57 12/Oct/10 0.59 12/Sep/10 0.16 12/Sep/10 1 1P/Halley
A.D. Dates ---------- 66/Jan/30 71 66/Jan/26 0.59 66/Mar/20 0.25 66/Mar/20 1 1P/Halley 141/Mar/26 41 141/Mar/22 0.58 141/Apr/22 0.17 141/Apr/22 -1 1P/Halley 178/Sep 80 < 2> 191/Oct < 2> 218/May 40 218/May/17 0.58 218/May/30 0.42 218/May/30 0 1P/Halley 240/Nov/10 39 240/Nov/10 0.37 240/Nov/30 1.00 240/Nov/20 1-2 (240 V1) 295/May 30 295/Apr/20 0.58 295/May/12 0.32 295/May/12 0 1P/Halley 374/Mar/03 32 374/Feb/16 0.58 374/Apr/02 0.09 374/Apr/02 -1 1P/Halley 390/Aug/21 26 390/Sep/05 0.92 390/Aug/18 0.10 390/Aug/18 -1 (390 Q1) < 2> 400/Mar/18 30 400/Feb/25 0.21 400/Mar/31 0.08 400/Mar/19 0 (400 F1) 442/Nov/09 100 442/Dec/15 1.53 442/Dec/07 0.58 442/Dec/07 1-2 (442 V1) 451/Jun/09 68 451/Jun/28 0.58 451/Jun/30 0.49 451/Jun/30 0 1P/Halley 565/Jul/22 100 565/Jul/15 0.82 565/Sep/13 0.54 565/Sep/13 0-1 (565 O1) 568/Jul/28 106 568/Aug/27 0.87 568/Sep/25 0.09 568/Sep/25 0 (568 O1) 607/Mar-Apr 30 607/Mar/15 0.58 607/Apr/19 0.09 607/Apr/19 -2 1P/Halley 684/Sep/06 33 684/Oct/02 0.58 684/Sep/07 0.26 684/Sep/07 1-2 1P/Halley 760/May/16 50 760/May/20 0.58 760/Jun/03 0.41 760/Jun/03 0 1P/Halley 770/May/25 62 770/Jun/05 0.58 770/Jul/10 0.30 770/Jul/10 1-2 (770 K1) 837/Mar/21 39 837/Feb/28 0.58 837/Apr/11 0.03 837/Apr/11 -3 1P/Halley < 3> 838/Nov/09 49 891/May/12 62 2 905/May/18 26 905/Apr/26 0.20 905/May/25 0.21 905/May/23 0-2 989/Aug/10 32 989/Sep/05 0.58 989/Aug/20 0.39 989/Aug/20 1-2 1P/Halley 1066/Apr/02 66 1066/Mar/20 0.58 1066/Apr/24 0.10 1066/Apr/24 -1 1P/Halley 1106/Feb/02 40 4 1132/Oct/03 24 1132/Aug/30 0.74 1132/Oct/07 0.04 1132/Oct/07 -1 (1132 T1) 1145/Apr/15 65 1145/Apr/18 0.58 1145/May/12 0.27 1145/May/12 0 1P/Halley 1222/Sep/02 36 1222/Sep/28 0.58 1222/Sep/06 0.31 1222/Sep/24 1-2 1P/Halley < 5> 1240/Jan/27 64 1240/Jan/21 0.67 1240/Feb/02 0.36 1240/Feb/02 0 (1240 B1) 1264/Jul/17 85 1264/Jul/20 0.82 1264/Jul/29 0.18 1264/Jul/29 0 (1264 N1) < 6> 1301/Sep/01 61 1301/Oct/25 0.58 1301/Sep/23 0.18 1301/Sep/23 1-2 1P/Halley 1378/Sep/26 15 1378/Nov/10 0.58 1378/Oct/03 0.12 1378/Oct/03 1 1P/Halley < 7> 1402/Feb/08 70 1402/Mar/21 0.38 1402/Feb/19 0.71 1402/Mar/12 -3 (1402 D1) < 8> 1456/May/26 44 1456/Jun/09 0.58 1456/Jun/19 0.45 1456/Jun/19 0 1P/Halley 1468/Sep/18 56 1468/Oct/07 0.85 1468/Oct/02 0.67 1468/Oct/02 1-2 (1468 S1) 1471/Dec/25 59 1472/Mar/01 0.49 1472/Jan/23 0.07 1472/Jan/23 -3 (1471 Y1) 1531/Aug/05 34 1531/Aug/26 0.58 1531/Aug/14 0.44 1531/Aug/27 1 1P/Halley 1532/Sep/02 120 1532/Oct/18 0.52 1532/Sep/21 0.67 1532/Oct/13 -1 (1532 R1) 1533/Jun/27 83 1533/Jun/15 0.25 1533/Aug/02 0.42 1533/Jun/27 0 (1533 M1) < 9> 1556/Feb/27 72 1556/Apr/22 0.49 1556/Mar/13 0.08 1556/Mar/14 -2 (1556 D1) 1577/Nov/01 87 1577/Oct/27 0.18 1577/Nov/10 0.63 1577/Nov/08 -3 (1577 V1)
Gregorian Calendar ------------------ 1618/Nov/16 67 1618/Nov/08 0.40 1618/Dec/06 0.36 1618/Nov/29 0-1 (1618 W1) 1664/Nov/17 75 1664/Dec/04 1.03 1664/Dec/29 0.17 1664/Dec/29 -1 (1664 W1) 1665/Mar/27 24 1665/Apr/24 0.11 1665/Apr/04 0.57 1665/Apr/20 -1 (1665 F1) <10> 1668/Mar/03 27 1668/Feb/28 0.07 1668/Mar/05 0.80 1668/Mar/08 1-2 (1668 E1) 1680/Nov/23 88 1680/Dec/18 0.01 1680/Nov/30 0.42 1680/Dec/29 1-2 (1680 V1) <11> 1682/Aug/15 41 1682/Sep/15 0.58 1682/Aug/31 0.42 1682/Aug/31 0-1 1P/Halley 1686/Aug/12 34 1686/Sep/16 0.34 1686/Aug/16 0.32 1686/Aug/27 1-2 (1686 R1) 1743/Nov/29 110 1744/Mar/01 0.22 1744/Feb/27 0.83 1744/Feb/20 -3 (1743 X1) <12> 1769/Aug/24 94 1769/Oct/08 0.12 1769/Sep/10 0.32 1769/Sep/22 0 Messier (1769 P1) <13> 1807/Sep/09 90 1807/Sep/19 0.65 1807/Sep/27 1.15 1807/Sep/20 1-2 Great Comet (1807 R1) 1811/Apr/11 260 1811/Sep/12 1.04 1811/Oct/16 1.22 1811/Oct/20 0 Great Comet (1811 F1) 1843/Feb/05 48 1843/Feb/27 0.006 1843/Mar/06 0.84 1843/Mar/07 <-3 Great March Comet (1843 D1) <14> 1858/Aug/20 80 1858/Sep/30 0.58 1858/Oct/11 0.54 1858/Oct/07 0-1 Donati (1858 L1) 1861/May/13 90 1861/Jun/12 0.82 1861/Jun/30 0.13 1861/Jun/27 0 Great Comet (1861 J1) <13> 1865/Jan/17 36 1865/Jan/14 0.03 1865/Jan/16 0.94 1865/Jan/24 1 Great Southern Comet (1865 B1) <15> 1874/Jun/10 50 1874/Jul/09 0.68 1874/Jul/23 0.29 1874/Jul/13 0-1 Coggia (1874 H1) 1882/Sep/01 135 1882/Sep/17 0.008 1882/Sep/16 0.99 1882/Sep/08 <-3 Great September Comet (1882 R1) <16> 1901/Apr/12 38 1901/Apr/24 0.24 1901/Apr/30 0.83 1901/May/05 1 Great Comet (1901 G1) 1910/Jan/13 20 1910/Jan/17 0.13 1910/Jan/18 0.86 1910/Jan/30 1-2 Great January Comet (1910 A1) <17> 1910/Apr/10 80 1910/Apr/20 0.59 1910/May/20 0.15 1910/May/20 0-1 1P/Halley 1927/Nov/27 32 1927/Dec/18 0.18 1927/Dec/12 0.75 1927/Dec/08 1 Skjellerup-Maristany (1927 X1) <18> 1965/Oct/03 30 1965/Oct/21 0.008 1965/Oct/17 0.91 1965/Oct/14 2 Ikeya-Seki (1965 S1) <19> 1970/Feb/10 80 1970/Mar/20 0.54 1970/Mar/26 0.69 1970/Mar/20 0-1 Bennett (1969 Y1) <20> 1976/Feb/05 55 1976/Feb/25 0.20 1976/Feb/29 0.79 1976/Mar/01 -1 West (1975 V1) <21> 1996/Mar/15 30 1996/May/01 0.23 1996/Mar/25 0.10 1996/Apr/20 1-2 Hyakutake (1996 B2) 1996/Sep/09 215 1997/Apr/01 0.91 1997/Mar/22 1.32 1997/Mar/26 -0.7 Hale-Bopp (1995 O1) <22> --------------------------------------------------------------------- Notes -----
< I>Reported by the Greek historian Ephorus to have split into two pieces.
< 2>The Chinese reported that the tail spanned more than 70 degrees.
< 3>The closest approach to the Earth that comet Halley has ever made. On Apr. 13, the comet's tail was more than 90 degrees in length.
< 4>This comet passed very close to the sun and is perhaps the progenitor of the sungrazing comets of 1882 and 1965 or that of 1843.
< 5>Korean observers reported the comet was visible during the daylight hours on September 9th (probably during twilight only).
< 6>On July 26, Chinese observers reported the tail spanning 100 degrees.
< 7>Chinese observers reported cloudy weather from October 11 until Nov. 9, at which time the comet had passed behind the sun.
< 8>In mid-March, the comet entered solar conjunction and there were reports that it was a daylight object for 8 days.
< 9>The comet was discovered emerging from solar conjunction.
<10>Last observed on April 20 as it approached solar conjunction.
<11>This was the first comet discovered with the aid of a telescope (on Nov. 14).
<12>Visible in daylight only 12 degrees from the Sun on February 27.
<13>Tail reported as longer than 90 degrees near Earth close approach.
<14>On the date of perihelion, this sungrazing comet was observed in daylight nearly one degree from the sun.
<15>Comet observed in southern hemisphere.
<16>The Great September comet was a brilliant object that was observed very close to the sun, and split into at least four separate pieces near perihelion. This comet and comet Ikeya-Seki in 1965 are believed to be members of the same family of sungrazing comets.
<17>This comet was easily observed on January 17 only 4.5 degrees from the sun. It is often confused with the later apparition of comet Halley in mid-1910.
<18>On December 18, this comet was seen in daylight only 5 degrees from the sun. At the end of December, the tail was reported to be nearly 40 degrees in length.
<19>Sungrazing comet Ikeya-Seki split into two or possibly three pieces near perihelion. Toward the end of October, the impressive tail reached lengths in excess of 45 degrees.
<20>The tail of comet Bennett reached 10 degrees in mid-March.
<21>Comet West's impressive broad tail reached a length of 30 degrees on March 8. Near perihelion, the comet split into four pieces.
<22>The observational interval is based on the time during which the comet had a total magnitude of 3.4 or brighter.