C / 1861 J1 (Great Comet)
| C / 1861 J1 (Great Comet) [i] | |
|---|---|
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| Artist's impression of the comet | |
| Properties of the orbit ( animation ) | |
| Orbit type | long-period |
| Numerical eccentricity | 0.9851 |
| Perihelion | 0.822 AU |
| Aphelion | 109.3 AU |
| Major semi-axis | 55.1 AU |
| Sidereal orbital period | ~ 409 a |
| Inclination of the orbit plane | 85.4 ° |
| Perihelion | June 12, 1861 |
| Orbital velocity in the perihelion | 46.3 km / s |
| history | |
| Explorer | John Tebbutt |
| Date of discovery | May 13, 1861 |
| Older name | 1861 II |
| Source: Unless otherwise stated, the data comes from JPL Small-Body Database Browser . Please also note the note on comet articles . | |
C / 1861 J1 (Great Comet) (also called Comet Tebbutt ) was a comet that could be seen with the naked eye in the summer of 1861 . Because of its extraordinary brightness and the imposing tail, it is one of the most spectacular of the great comets .
Discovery and observation
On the evening of May 13, 1861, in Windsor, New South Wales , Australia , the farmer and amateur astronomer John Tebbutt was scanning the western sky for comets with a small telescope when he found a faint foggy object whose brightness he estimated to be about 5 mag . His star catalogs showed no nebula at this point and he suspected it was a comet, so he decided to keep observing it for the next few nights. On the evening of May 14th, however, it initially showed no noticeable proper motion, so that he had doubts that it would be a comet. It was not until May 21, eight days after its discovery, that he was able to observe the object again and now for the first time he was able to detect movement against the star background and sent a report to William Scott from the Sydney Observatory and the Sydney Morning Herald , May reported about it. Scott was able to observe the comet on May 22nd and on May 27th he was able to see the comet with the naked eye for the first time.
At the time of its discovery, the comet was still 0.99 AU from the Sun and 1.27 AU from Earth , and was even closer to both in early June. On June 3, the comet was seen at dawn in Cape Town with a magnitude of 2-3 mag and with a 3 ° long tail pointing south. On June 8th it was already clearly visible to the naked eye, the length of the tail had grown to 18 °. Only four days later it was already 40 °. A week later, the tail was "longer than that of any other comet seen in the [southern] hemisphere since the memorable one of 1843, " a Herald correspondent wrote on June 19. On June 20, it was found that the comet's tail had split into two parts, a longer one of 40 ° long and a shorter one of 5 ° long, which were wide apart.
After the comet could initially only be observed from the southern hemisphere , it had moved quickly north and could be seen in the northern hemisphere towards the end of June - since the news of Tebbutt's discovery had in some cases not yet got there, this was surprising for many observers. On June 30th, when the comet was closest to Earth, it could be seen before sunset and the brightness that emanated from the tail at night was so strong that it cast shadows on a white wall, like Johann Friedrich Julius Schmidt in Athens reported. The brightness of the comet's nucleus was somewhere between that of Venus and Jupiter . The coma was 1 ° in diameter and the tail was very impressive with a number of rays. Its length has been estimated by various observers to be between 30 and 120 °. The unusual surface brightness of the tail was caused by the forward scattering of sunlight by dust particles in the coma, as the comet stood between the sun and earth and its tail almost pointed towards earth. It may even go through part of the dust tail, as there were very many conspicuous luminous phenomena in the atmosphere in those days , as reported by John Russell Hind in England as well as Tebbutt in Australia. Telescopic observations of the comet's nucleus also showed strange effects such as veils and rays of light.
After this great spectacle at the beginning of July, the brightness of the comet noticeably decreased again. While at first magnitudes around 1 mag and tail lengths of 45 to 100 ° were observed, on July 5th there were reports of 85 ° length of the main tail and 30 ° length of the secondary tail. David Livingstone was able to observe the comet on July 6th while traveling on the Shire River in Malawi .
On July 8, the secondary tail appeared to have disappeared, while the main tail was still estimated to be 15–60 ° in length with noticeable stripes. The veils of light in the coma were also gone. As the distance between the sun and earth increased, the comet's brightness decreased rapidly. On July 12th it was still 3 mag with 20 to 30 ° tail length and in mid-August 5 mag with 2.5 ° tail length. The last observation with the naked eye was made on August 15th by Eduard Heis . Telescopic observations could be continued until April 30 of the following year by Friedrich August Theodor Winnecke and Otto Wilhelm von Struve in Russia , when the brightness of the comet sank below 14 mag.
The comet reached a magnitude of 0 mag on June 27, 1861. According to other data, the brightness even reached −2 mag.
Effects on the zeitgeist
Tebbutt had seen from his observations that the comet was moving approximately towards Earth. He was able to calculate a "rough approximate orbit" of the comet, which was published in the Sydney Morning Herald , as well as the prediction that the comet would approach Earth around June 29 and that it would pass the comet's tail at a short distance. Tebbutt also suspected that the comet might become visible in the daytime sky around this time . These predictions did not seem to cause any consternation among the readers, in contrast to the effect of similar predictions 50 years later, when the earth passed through its tail on the return of Halley's comet .
The comet attracted a great deal of public attention worldwide and it was widely reported in newspapers. Its appearance coincided with the outbreak of the American Civil War , which is why it was also known as the great war comet in the United States . There were a large number of caricatures on this occasion in which the comet was portrayed with the head of various contemporary politicians or military personnel, such as Abraham Lincoln or General Winfield Scott . The satirical magazine Punch published a cartoon showing dinosaurs watching the comet and recognizing an old friend in it.
Four crew members of the Peruvian had survived the shipwreck off the coast of Queensland in 1846 . One of them, James Morrill, lived among the Aborigines for 17 years . In his memoirs, published in 1864, he recalls seeing a comet. This could have been Comet Tebbutt. The Aborigines told him that the comet was the ghost of one of their tribe members who had been killed in a distant war and was coming home from the clouds on the horizon.
Scientific evaluation
JFJ Schmidt was able to determine a synchronous periodicity of both of about 25.5 days by evaluating the observations of the tail length and the comet's diameter and assumed that both were influenced by the same factor.
After the first computation of a parabolic orbit by Tebbutt shortly after the discovery, numerous further attempts were made to determine the orbital elements of the comet with the availability of further observational data . by Maurice Loewy , John Russell Hind, Asaph Hall, and Horace Parnell Tuttle . Each of these determined parabolic orbits, in one case also a hyperbolic orbit. In September 1861 Arthur von Auwers was able to determine the comet's true orbit for the first time as elliptical . When the comet had already disappeared again, orbital elements could be calculated that covered the entire time of its visibility. Heinrich Kreutz determined the comet's orbit parameters in 1880, which indicate an orbital period of around 409 years. The comet thus has the shortest orbital time of all great comets after Halley's comet.
Kreutz calculated these values before the advent of modern computers and calculation methods and was only able to take into account the most important interfering influences from four planets . In 2013, RL Branham calculated more precise orbital elements for the comet using 2362 observation data between May 1861 and March 1862 and taking into account the interfering influences of all planets and other mathematical methods.
Orbit
Kreutz was able to calculate an elliptical orbit for the comet from 1159 observation data over a period of 339 days, which is inclined by around 85 ° to the ecliptic . The comet's orbit is almost perpendicular to the planets of the planets. At the point of the orbit closest to the sun ( perihelion ), which the comet passed on June 12, 1861, it was located at a distance of 123.0 million km from the sun in the area between the orbits of Venus and the earth. On June 30th, it reached the closest approximation to the earth at about 19.8 million km (0.13 AU ). On July 7th, it approached Mercury up to about 88.2 million km, there were no noteworthy approaches to the other small planets.
The relatively imprecise orbital elements, which are given in the JPL Small-Body Database and which do not take into account non-gravitational forces on the comet, still come from Kreutz. Marsden , Sekanina, and Everhart used the same starting data in their computation of the comet's original and future orbits. According to this, long before its passage through the inner solar system in 1861 , its orbit still had an eccentricity of about 0.98374 and a semi-major axis of about 50.8 AU, so that its orbital period was about 362 years. Thus the previous passage of perihelion could have occurred around the year 1499. There are no reports of a conspicuous comet from this year. From the Far East , however, there are reports from 1500 about the sighting of a comet. According to I. Hasegawa and S. Nakano , the orbital elements of this comet C / 1500 H1 , which were derived from 10 observations, could be interpreted to the effect that it could have been the same comet as the one in 1861, the orbital period would then be before the last one Perihelion is about 361 years.
Due to the gravitational pull of the planets, in particular due to the relatively close passing of Saturn around January 31, 1858 at a distance of about 3 ¾ AU and at Jupiter around January 5, 1860 at a distance of about 1 ¾ AU, based on Kreutz’s orbit calculation, its orbital eccentricity would be about 0.98491 and its semi-major axis was enlarged to about 54.8 AU, so that its orbital period increased to about 406 years. The next perihelion of the comet would therefore take place around the year 2267.
The improved determination of the orbit by RL Branham deviates slightly but significantly from Kreutz's orbital elements, in particular according to Branham the orbit of the comet originally had an eccentricity of about 0.98256 and a semi-major axis of about 47.4 AU, so that its orbital time is 326 years ago and the previous passage of the perihelion would have occurred around the middle of 1535 (uncertainty ± 4 months). Branham does not rule out a connection with the comet of 1500. a The future orbit of the comet would have an eccentricity of around 0.98373 and a semi-major axis of around 50.9 AU, so that its orbital period would be around 363 years. If the celestial body reaches the point of its orbit furthest from the sun ( aphelion ) around the year 2042 , it will be about 15.1 billion km away from the sun, almost 101 times as far as the earth and 3 so times as far as Neptune . Its orbital speed in the aphelion is then only about 0.37 km / s. The next perihelion of the comet might take place in the second half of 2223 (uncertainty ± 5 months).
Reception in literature
The comet was dealt with in detail in a separate chapter of the work L'espace céleste et la nature tropicale by Emmanuel Liais .
In the chronicle of the Franciscan monastery Reutte the comet was described as follows:
"About this time was also a wonderful Comet star to see which, although in its rays slightly smaller than that of 1859, b but of significant size was -. Its extension was 20 degrees"
See also
Web links
- C / 1861 J1 (Great Comet of 1861) on Cometography.com (English)
- The Comet of 1861 on The Gallery of Natural Phenomena
Individual evidence
- ^ N. Lomb: The discovery of the Great Comet of 1861 by John Tebbutt. Retrieved September 9, 2014 .
- ^ DAJ Seargent: The Greatest Comets in History: Broom Stars and Celestial Scimitars . Springer, New York 2009, ISBN 978-0-387-09512-7 , pp. 136-142.
- ↑ a b G. W. Kronk: Cometography - A Catalog of Comets, Volume 2. 1800-1899 . Cambridge University Press, Cambridge 2003, ISBN 0-521-58505-8 , pp. 293-302.
- ^ P. Grego: Blazing a Ghostly Trail: ISON and Great Comets of the Past and Future . Springer, Cham 2013, ISBN 978-3-319-01774-7 , pp. 116-117.
- ↑ DK Yeomans: NASA JPL Solar System Dynamics: Great Comets in History. Retrieved June 17, 2014 .
- ^ P. Moore, R. Rees: Patrick Moore's Data Book of Astronomy . Cambridge University Press, Cambridge 2011, ISBN 978-0-521-89935-2 , p. 270.
- ↑ Americas studies blog - The Great Comet of 1861 and the Civil War. British Library, accessed September 9, 2014 .
- ↑ 1861 Punch Dinosaurs & Comet Cartoon. pixels, accessed September 8, 2020 .
- ^ DW Hamacher, RP Norris: Comets in Australian Aboriginal Astronomy . In: Journal for Astronomical History & Heritage. Volume 14, No. 1, 2011, pp. 31-40. ( PDF; 623 kB )
- ↑ a b R. L. Branham, Jr .: A New Orbit for Comet C / 1861 J1 (Great Comet of 1861). In: Revista Mexicana de Astronomía y Astrofísica. Vol. 50, 2014, pp. 109-118. ( PDF; 408 kB ) Note: The oscillating elements given in Table 6 are incorrect with regard to i and ω. Instead, the values from Table 4 should be used.
- ↑ C / 1861 J1 (Great Comet) in the Small-Body Database of the Jet Propulsion Laboratory (English).
- ^ BG Marsden, Z. Sekanina, E. Everhart: New osculating orbits for 110 comets and analysis of original orbits for 200 comets. In: The Astronomical Journal. Volume 83, No. 1, 1978, pp. 64-71 doi: 10.1086 / 112177 . ( PDF; 890 kB )
- ^ I. Hasegawa, S. Nakano: Periodic Comets Found in Historical Records. In: Publications of the Astronomical Society of Japan. Volume 47, No. 5, 1995, pp. 699-671 bibcode : 1995PASJ ... 47..699H . ( PDF; 331 kB )
- ↑ A. Vitagliano: SOLEX 12.1. Accessed July 9, 2020 .
- ^ E. Liais: L'espace céleste et la nature tropicale: description physique de l'univers, d'après des observations personnelles faites dans les deux hémisphères. Garnier Frères, Paris 1865, pp. 296-314. ( PDF; 1.9 MB )
- ↑ PM Hollaus: Heavenly Horror Messengers - Description of special heavenly phenomena in chronicles of the Tyrolean Franciscan Province. In: Austria franciscana. No. 8, 2011, pp. 91-97. ( PDF; 485 kB )