C / 1892 E1 (Swift)

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C / 1892 E1 (Swift) [i]
Comet Swift on April 4th and 6th, 1892
Comet Swift on April 4th and 6th, 1892
Properties of the orbit ( animation )
Period:  April 12th, 1892 ( JD 2,412,200.5)
Orbit type long-period
Numerical eccentricity 0.9987
Perihelion 1.027 AU
Aphelion 1617 AE
Major semi-axis 809 AE
Sidereal period ~ 23,000 a
Inclination of the orbit plane 38.7 °
Perihelion April 7, 1892
Orbital velocity in the perihelion 41.6 km / s
history
Explorer Lewis A. Swift
Date of discovery March 6, 1892
Older name 1892 I, 1892a
Source: Unless otherwise stated, the data comes from JPL Small-Body Database Browser . Please also note the note on comet articles .

C / 1892 E1 (Swift) is a comet that could be seen with the naked eye in 1892 .

Discovery and observation

Lewis A. Swift was a renowned astronomer , 72 years old, and since 1886 director of Warner's private observatory in Rochester, New York . He had already discovered 9 comets and was working on a catalog of star nebulae when he discovered his tenth comet on the morning of March 6, 1892. This should be the brightest comet that has been seen in the northern hemisphere since 1882 .

The news of the comet's discovery was received one day later at the Kiel observatory and from there it was telegraphed all over the world, so that further observations took place in Cape Town on March 8th . Even John Tebbutt in Australia was able to locate and measure its position until early May on March 11, the comet.

At the time of its discovery, only a blurred spot with a magnitude of 4 mag, the comet continued to move towards the Sun in the course of March, becoming steadily brighter and starting to form a tail . At a point in time between the end of March and the end of April, it was also discovered by Chinese astronomers as a "broom star". At the time of its closest approach to the sun in early April, the brightness had reached 3 mag and the tail had a length of 20 ° . The tail was split several times into foggy stripes and changed in terms of number and relative brightness of the stripes in a short time.

From the beginning of May the comet moved away from the sun and earth. The brightness fell in the course of the month from about 4 to about 6 mag and the tail still had a length of about 1–2 ° at the end of May. From the beginning of June the comet could hardly be seen with the naked eye and by the end of August the brightness had fallen to 8 mag. The last position determinations took place in mid-February 1893.

Scientific evaluation

From the comet u. a. Wide-angle photographs taken by Edward Barnard at the Lick Observatory and William Henry Pickering . The recordings showed the unusual shape of the tail and documented what visual observers had also noticed, namely that the tail showed significant changes in a short time. Sometimes the tail seemed to be composed of up to a dozen narrow rays and other times only two broad ones. Together with the observations made the following year on comet C / 1893 U1 (Brooks) , this led to the realization that there is an interaction between the head of the comet and the changes observed in the tail.

The light from the comet was examined spectroscopically by Miklós Konkoly-Thege and Eugen von Gothard . They were able to observe the comet-typical emission lines of carbon (C 2 ).

Orbit

For the comet, an elliptical orbit could be determined from 81 observation data over a period of almost a year by Marsden , which is inclined by around 39 ° to the ecliptic . At the point of the orbit closest to the sun ( perihelion ), which the comet traversed on April 7, 1892, it was located at a distance of about 153.6 million km from the sun in the area of ​​the earth's orbit . On March 8th it had already passed Mars in 68.1 million km and on March 27th it had reached the closest approach to Earth with 1.05 AU / 157.3 million km. He had passed the point of his orbit that was closest to the earth's orbit around March 21st, albeit at a point that was far from the earth's position at that time and to which the earth only came close two months later.

The comet moves in an extremely elongated elliptical orbit around the sun. According to the orbital elements , which are afflicted with a certain uncertainty, its orbit before its passage through the inner solar system in 1892 still had an eccentricity of about 0.9988 and a semi-major axis of about 845 AU, so that its orbit period was about 24,500 years. Due to the gravitational pull of the planets, in particular due to the relatively close passages of Saturn on June 20, 1890 in just under 7 AU and to Jupiter on May 12, 1893 in only about 1.6 AU, its orbital eccentricity was reduced to about 0.9982 and its Semi-major axis reduced to about 570 AU, so that its orbital period was shortened to about 13,600 years.

See also

Web links

Individual evidence

  1. ^ A. Krueger: Discovery of a Comet by Swift in Rochester 1892 March 6. In: Astronomische Nachrichten. Vol. 129, 1892, pp. 119-120, bibcode : 1892AN .... 129Q.119. .
  2. Jump up ↑ J. Tebbutt: Results of Observations of Wolf's Comet (II.) 1891, Swift's Comet (I.) 1892, and Winnecke's Periodical Comet, 1892, at Windsor, New South Wales - Swift's Comet (I.) 1892. In: Journal and Proceedings of the Royal Society of New South Wales. Vol. XXVI, 1892, p. 336 JPG; 96 kB .
  3. ↑ AM Clerke: A Popular History of Astronomy During the Nineteenth Century. Adam and Charles Black, Fourth Edition, London 1908, pp. 368-369.
  4. ↑ GW Kronk: Cometography - A Catalog of Comets, Volume 2. 1800-1899 . Cambridge University Press, Cambridge 2003, ISBN 0-521-58505-8 , pp. 675-681.
  5. ↑ PT Wlasuk: 'So much for fame!': The Story of Lewis Swift. In: Quarterly Journal of the Royal Astronomical Society. Vol. 37, 1996, pp. 683-707, bibcode : 1996QJRAS..37..683W .
  6. ↑ RJM Olsen, JM Pasachoff: Fire in the Sky: Comets and Meteors, the Decisive Centuries, in British Art and Science. Cambridge University Press, Cambridge 1998, ISBN 0-521-63060-6 , pp. 256-257.
  7. ^ N. v. Konkoly: Spectroscopic observation of the comet 1892 ... (Swift March 6). In: Astronomical News. Vol. 129, 1892, pp. 259-260, bibcode : 1892AN .... 129..259V .
  8. ↑ E. v. Gothard: Spectrographic observation of the Comet 1892 ... (Swift March 6). In: Astronomical News. Vol. 129, 1892, pp. 405-408, bibcode : 1892AN .... 129..405V .
  9. ↑ C / 1892 E1 (Swift) in the Small-Body Database of the Jet Propulsion Laboratory (English).Template: JPL Small-Body Database Browser / Maintenance / Alt
  10. ↑ SOLEX 11.0 A. Vitagliano. Archived from the original on September 18, 2015 ; accessed on May 2, 2014 .
  11. ^ BG Marsden, Z. Sekanina, E. Everhart: New Osculating Orbits for 110 Comets and Analysis of Original Orbits for 200 Comets. In: The Astronomical Journal. Vol. 83, no. 1, 1978, pp. 64-71 doi: 10.1086 / 112177 .