C / 1843 D1 (Great March Comet)

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C / 1843 D1 (Great March Comet) [i]
The Comet of 1843 seen from Aldridge Lodge, Tasmania
The Comet of 1843 seen from Aldridge Lodge, Tasmania
Properties of the orbit ( animation )
Period:  February 27, 1843 ( JD 2,394,259,411)
Orbit type long-period
Numerical eccentricity 0.999914
Perihelion 0.00553 AU
Aphelion 128.5 AU
Major semi-axis 64.3 AU
Sidereal period ~ 515 a
Inclination of the orbit plane 144.4 °
Perihelion February 27, 1843
Orbital velocity in the perihelion 567 km / s
history
Explorer
Date of discovery February 6, 1843
Older name 1843 I.
Source: Unless otherwise stated, the data comes from JPL Small-Body Database Browser . Please also note the note on comet articles .

C / 1843 D1 (Great March Comet ) was a comet that could be seen with the naked eye in the daytime sky in 1843 . It is considered to be one of the most magnificent comets ever seen and is often cited as the most beautiful of the 19th century . Due to its extraordinary brightness, it is counted among the " Great Comets ".

Discovery and observation

The earliest observations of this comet were made on the evening of February 5, 1843 (local time) and again on February 11. These anonymous observations, without further details, were mentioned in a New York newspaper according to a report by Johann Franz Encke . Encke calculated the comet's orbit and found that the two reported observations were likely real. The comet was rapidly approaching the Sun and was likely to be seen only a few more times in Bermuda , Philadelphia, and Puerto Rico prior to its perihelion passage in late February . But although the comet was getting closer and closer to the sun, its brightness increased so much that it could be seen very close to the sun by an observer in Chile on a bright day on February 27th.

On February 27, the core of the comet came from the earth as seen from about 21:00 UT for about 55 minutes behind the sun over and reappeared on the other side around the time of its closest approach to the sun. It moved a little further away from the sun and then moved towards it again, so that it then passed in front of the sun again for about 1 hour at around 11:30 p.m. UT. However, these events were not observed.

Already on the following day there were numerous sighting reports from Italy , many people saw the comet as “a very beautiful star” on a bright day with a 4 to 5 ° long tail about 3 ° from the sun. There were also numerous observations in North America . In China it was recorded that a large "broom star" was sighted that day. The next day, when the comet was 8 ° from the Sun, the comet's tail reached into the evening sky, which resulted in further independent discoveries of the comet. So there were reports u. a. from Tasmania , Mauritius , Brazil , New Zealand and Australia .

The Great Comet of 1843

On March 3rd, the now 25 ° long tail seems to have forked, as Charles Piazzi Smyth from South Africa reported. Although the comet's core also shone surprisingly bright on March 4th, the bright silvery tail, which stretched from the west almost to the zenith , was the more interesting thing for most observers on the following days. Between March 10 and March 20, the length of the tail was generally estimated to be between 40 and 50 °; on March 21, Johann Friedrich Julius Schmidt was able to observe a tail of 64 ° length, parts of which could be seen long after the head had already gone down. The tail was of remarkably uniform and high intensity over much of its length, and was relatively narrow and straight to slightly curved and slightly forked at the end.

The comet faded rapidly in late March, and by April 3 it was barely visible to the naked eye. The comet was last observed with a telescope on April 19 by Thomas Maclear in South Africa.

The comet reached a brightness of <-3 mag on March 7th .

Effects on the zeitgeist

This comet made a strong impression on the people of its time, especially in terms of its brightness and magnificence. Maclear recalled that Comet C / 1811 F1 was n't half as glamorous as this one. Other contemporaries praised the comet of 1843 over comets C / 1858 L1 (Donati) and C / 1882 R1 (Great September Comet ) .

Superstitious people saw the appearance of the comet as a sign of Judgment Day , but primitive peoples were also terrified. The Aborigines in South Australia hid in caves and saw the comet as a calamity, especially for the white colonists.

Charles Piazzi Smyth: Daylight View over Table Bay Showing the Great Comet of 1843

Scientific evaluation

Comets as close to the Sun as the Great Comet of 1843 has puzzled astronomers for over 300 years. Ever since it was proven that the Great Comet C / 1680 V1 had almost grazed the surface of the sun at its closest approximation of only 200,000 km, they wondered on the one hand how comets can survive something like this, and on the other hand, when such a sun streamer had before could have appeared.

For a long time, three or four comets from the last third of the 17th century (not the comet of 1680) were considered the most likely candidates for an earlier appearance of the comet of 1843 . Values ​​of 175 years down to the completely impossible 7 years have been assumed as the orbital period of the comet. Direct calculations based on the observations of the comet showed, however, that the orbital period probably cannot be shorter than 400 to 500 years.

When the Great Southern Comet C / 1880 C1 appeared in 1880 , orbiting in almost the same orbit, the proponents of a 35- to 40-year period had a great time again. When, in 1882, the Great September Comet C / 1882 R1 reappeared with a very similar orbit, it was already assumed that this sun streak would have been greatly slowed down by friction in a solid medium surrounding the sun at each return. However, this turned out to be incorrect, as the observation data of the comet from 1882 showed an orbital period of several centuries.

The conclusion was that there must be a number of different comets moving in practically the same sun-grazing orbit. Daniel Kirkwood was the first to suggest in 1880 that the sun-grazing comets formed such a comet group. He suspected that the comets of 1843 and 1880 could be fragments of the comet of -371 , which, according to the report of the Greek historian Ephorus, had broken in two. The comet of 1882 also broke into several fragments as it passed the sun. A few years later, another member of this comet group was identified with the great southern comet C / 1887 B1 .

The sun streaker was then examined very intensively from 1888 to 1901 by Heinrich Kreutz , who suspected that all members of the comet group later named after him, the Kreutz group , descended from an original body that broke when it passed the sun. He identified other possible members of the group, and further group members appeared in the 20th century in 1945, 1963, 1965 and 1970.

In 1967 Brian Marsden examined the orbits of the previously known comets of the Kreutz group and showed that their members can be divided into two subgroups according to their slightly different orbital elements . The second brightest observed solar stripes in the last two centuries, C / 1843 D1, together with C / 1880 C1, are the most important representatives of subgroup I. As a result, there have been many attempts to theoretically record the possible decay processes and resulting trajectories of the solar stripes, especially through Zdenek Sekanina and others.

Charles Piazzi Smyth: The Great Comet of 1843

Marsden presented a scenario in 1989 in which the two comets C / 1843 D1 and C / 1880 C1 could be fragments of a common precursor comet that would have broken if it had passed the sun around 1487. This previous comet could in turn have been a fragment of the comet from -371. In this case, however, the orbital period of the comet from 1843 would only have been around 360 years, which contradicts previous knowledge. In addition, there are no reports of sun-grazing comets from the late 15th century .

In very extensive investigations, Sekanina and Paul W. Chodas developed new theories about the origin and development of the Kreutz comet group, which currently reflect the current state of knowledge. According to the model of the two super fragments, it can be assumed that all the sun streakers of the Kreutz group descend from a very large predecessor comet with a diameter of almost 100 km, which may have been in the late 4th century or early 5th century a few decades before it passed the sun has broken in two roughly equal parts. The two super fragments made one more orbit around the sun and super fragment I reappeared in 1106 as the famous sun streaker X / 1106 C1 . Superfragment II appeared only a few years earlier or later, but apparently escaped observation due to unfavorable viewing conditions as there are no reports about it. Both super fragments broke into further fragments ( cascading fragmentation ) shortly after they had passed extremely close to the sun at that time, internally damaged by the enormous tidal forces : Superfragment I first split into two further parts, the first appeared to be a few to tens of kilometers in size later than comet C / 1843 D1, the other part disintegrated again two years later into the two sun streaks, which appeared later as comets C / 1880 C1 and C / 1887 B1. The descent of comet C / 1843 D1 from comet X / 1106 C1 had already been suggested by Ichiro Hasegawa and Syuichi Nakano after evaluating historical reports. The comet from -371, however, as it turned out, had no relation to the Kreutz group.

According to this theory, there was still a problem for comet C / 1843 D1: In 1901 Kreutz had determined orbital parameters of the comet from 150 observation data over a period of 45 days, which indicated an orbital period of 512 years. This period also differs markedly from that of other sun grazes of the Kreutz group, which could be precisely determined. Before the advent of modern computers, Kreutz had calculated these values ​​using outdated mathematical methods and was unable to take into account the interference from the planets. In 2008, Sekanina and Chodas carried out new determinations of the orbital elements of the comet using modern mathematical methods, taking into account all planetary disturbances, relativistic effects and current reference data from comparison stars and a re-evaluation of 127 observation data. The calculation resulted in a probable orbital period of the comet between 600 and 800 years. This confirmed the comet's origin as a large (perhaps the largest) fragment of the sun-grazing comet X / 1106 C1 as possible and likely.

The following information is based on the track elements from Sekanina & Chodas (Solution II). They differ only minimally from the orbital elements from Kreutz specified in the info box, but a slightly larger eccentricity of 0.999933 leads to a semi-major axis of 82.0 AU and a significantly longer rotation time .

Orbit

An elliptical orbit could be determined for the comet , which is inclined by around 144 ° to the ecliptic . It thus runs in the opposite direction (retrograde) like the planets through its orbit. At the point of the orbit closest to the sun ( perihelion ), which the comet traversed on February 27, 1843, it was only 120,000 km at a distance of 0.82 million km from the sun. H. a good 1/6 of a solar radius over its surface. On January 27, it had already approached the earth to within 0.87 AU / 129.9 million km. On February 28th, it came close to Mercury up to 59.8 million km and Venus up to 104.8 million km, and on March 5, it came close to Earth again to 0.84 AU / 126.0 Million km.

The comet moves in an extremely elongated elliptical orbit around the sun. According to recent studies, the comet is probably a fragment of the sun-grazing comet X / 1106 C1 , after which its orbital period to its last passage through the inner solar system would have been 737 years. Under this assumption and with its unchanged existence, it could reach the point furthest from the sun ( aphelion ) of its orbit around the year 2190 , where it would be about 23 billion km from the sun, almost 160 times as far as the earth and over 5 -time as far as Neptune . Its orbital speed in aphelion is only about 0.01 km / s. The next perihelion of the comet could then possibly take place around the year 2540.

However, it is much more likely that the comet, like its direct predecessors and many other members of the Kreutz group, will continue to disintegrate. Such a spontaneous decay can occur at any point in its subsequent orbit around the sun, but when the fragments return to the inner solar system depends heavily on where and when this breakup happens (or has already happened). After decay, individual fragments could have new orbital times in a wide range from ½ to several times the old orbital period and could thus reappear sometime after the 22nd century at the earliest or after more than a thousand years.

Trivia

  • The appearance of the comet is the subject of film in the German cinema and homeland film The Other Home - Chronicle of a Longing by filmmaker Edgar Reitz . In addition to a trick representation of the comet passage, the impression that the comet left on the inhabitants of the fictional community of Schabbach is shown.

See also

Magazine articles

Web links

Commons : Great Comet of 1843  - Collection of images, videos and audio files

Individual evidence

  1. ↑ a b c D. AJ Seargent: The Greatest Comets in History: Broom Stars and Celestial Scimitars . Springer, New York 2009, ISBN 978-0-387-09512-7 , pp. 208-211.
  2. ^ GW Kronk: Cometography - A Catalog of Comets. Volume 2: 1800-1899 . Cambridge University Press, 2003, ISBN 0-521-58505-8 , pp. 129-137.
  3. ^ Donald K. Yeomans: NASA JPL Solar System Dynamics: Great Comets in History. Retrieved June 17, 2014 .
  4. ^ DW Hamacher, RP Norris: Comets in Australian Aboriginal Astronomy. In: Journal for Astronomical History & Heritage. Vol. 14, No. 1, 2011, pp. 31-40 ( bibcode : 2011JAHH ... 14 ... 31H ).
  5. ↑ BG Marsden: The Sungrazing Comet Group. In: The Astronomical Journal. Vol. 72, No. 9, 1967, pp. 1170-1183 ( bibcode : 1967AJ ..... 72.1170M ).
  6. ^ Zdeněk Sekanina: Problems of Origin and Evolution of the Kreutz Family of Sun-grazing Comets. In: Acta Universitatis Carolinae. Mathematica et Physica. Vol. 8, No. 2, 1967, pp. 33-84 ( PDF; 4.73 MB ).
  7. ↑ BG Marsden: The Sungrazing Comet Group. II. In: The Astronomical Journal. Vol. 98, No. 6, 1989, pp. 2306-221 ( bibcode : 1989AJ ..... 98.2306M ).
  8. ↑ Zdenek Sekanina, Paul W. Chodas: Fragmentation Hierarchy of Bright Sungrazing Comets and the Birth and Orbital Evolution of the Kreutz System. I. Two-Superfragment Model. In: The Astrophysical Journal. Vol. 607, 2004, pp. 620-639 doi: 10.1086 / 383466 .
  9. ↑ Zdenek Sekanina, Paul W. Chodas: Fragmentation Hierarchy of Bright Sungrazing Comets and the Birth and Orbital Evolution of the Kreutz System. II. The Case for Cascading Fragmentation. In: The Astrophysical Journal. Vol. 663, 2007, pp. 657-676 doi: 10.1086 / 517490 .
  10. ^ I. Hasegawa, S. Nakano: Possible Kreutz Sungrazing Comets Found in Historical Records. In: Publications of the Astronomical Society of Japan. Vol. 53, 2001, pp. 931-941. ( PDF; 312 kB ).
  11. ^ Zdenek Sekanina, Paul W. Chodas: A New Orbit Determination for Bright Sungrazing Comet of 1843. In: The Astrophysical Journal. Vol. 687, 2008, pp. 1415-1422 doi: 10.1086 / 592081 .
  12. ↑ C / 1843 D1 (Great March Comet) in the Small-Body Database of the Jet Propulsion Laboratory (English).
  13. ↑ SOLEX 11.0 A. Vitagliano. Archived from the original on September 18, 2015 ; accessed on May 2, 2014 .