C / 1831 A1 (Great Comet)
| C / 1831 A1 (Great Comet) [i] | |
|---|---|
| Properties of the orbit ( animation ) | |
| Orbit type | parabolic |
| Numerical eccentricity | 1.0 |
| Perihelion | 0.126 AU |
| Inclination of the orbit plane | 135.3 ° |
| Perihelion | December 28, 1830 |
| Orbital velocity in the perihelion | 118.7 km / s |
| history | |
| Explorer | John Herapath |
| Date of discovery | January 7, 1831 |
| Older name | 1830 II |
| Source: Unless otherwise stated, the data comes from JPL Small-Body Database Browser . Please also note the note on comet articles . | |
C / 1831 A1 (Great Comet) was a comet that could be seen with the naked eye in 1831 . Due to its brightness, some count it among the " great comets ".
Discovery and observation
A few weeks before its perihelion passage on December 28, 1830, the comet in the southern hemisphere must have been a bright object in the morning sky , at the end of the month it was even a spectacular phenomenon in the evening sky due to its close proximity to the sun , but at that time it still remained unobserved.
The comet then passed the Sun on December 28, 1830, at a distance of only 4 ° , but was only discovered 10 days later on the evening of January 7, 1831 by the English physicist John Herapath . He reported that "the tail was almost perpendicular to the horizon, sloping slightly to the south, of a white color and apparently 1–2 ° long". He estimated the brightness to be about 2 mag. Further independent discoveries were made a little later and on the following days in Massachusetts , England and by Wilhelm von Biela in Bozen .
The comet could still be observed with the naked eye in the course of January, but by the middle of the month its brightness had fallen to 4 mag, the tail was still 3 ° long. In February the comet could be seen with telescopes and a. be followed up by Friedrich Bernhard Gottfried Nicolai in Mannheim and Heinrich Wilhelm Olbers in Bremen , in March two final position determinations were made and the last observation finally took place on March 19, when he was only very faintly visible.
The comet reached a maximum observed brightness of about 2 mag.
Orbit
From 61 observation data over a period of 46 days, only a parabolic orbit with limited precision could be determined for the comet, which is inclined by around 135 ° 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 passed on December 28, 1830, it was located within the orbit of Mercury at a distance of about 18.8 million km from the sun . As early as December 9th, it had come close to Earth for the first time to around 0.69 AU / 102.6 million km and on December 27th to Mercury up to 41.7 million km. On December 29th, it approached Venus up to about 93.9 million km and on February 16, 1831 there was a second even closer passage of the earth at a distance of about 0.53 AU / 79.8 million km.
When the comet appeared in 1831, the eccentricity of its orbit was slightly increased by the gravitational pull of the planets. Due to the uncertain initial data, however, it cannot be deduced with certainty whether the comet is now definitely moving on a hyperbolic orbit. It is unlikely to return to the inner solar system , or will return many tens or hundreds of thousands of years later .
See also
Individual evidence
- ^ J. Herapath: Comet seen, January 7, 1831. In: Monthly Notices of the Royal Astronomical Society. Vol. 2, 1831, pp. 6-7. ( bibcode : 1831MNRAS ... 2 .... 6H ).
- ↑ GW Kronk: Cometography - A Catalog of Comets, Volume 2. 1800-1899 . Cambridge University Press, Cambridge 2003, ISBN 0-521-58505-8 , pp. 95-96.
- ^ John E. Bortle: International Comet Quarterly - The Bright-Comet Chronicles. Retrieved July 23, 2015 .
- ↑ C / 1831 A1 (Great Comet) in the Small-Body Database of the Jet Propulsion Laboratory (English).
- ↑ SOLEX 11.0 A. Vitagliano. Archived from the original on September 18, 2015 ; accessed on May 2, 2014 .