C / 1825 N1 (Pons)
| C / 1825 N1 (Pons) [i] | |
|---|---|
| Properties of the orbit ( animation ) | |
| Orbit type | long-period |
| Numerical eccentricity | 0.9954 |
| Perihelion | 1.241 AU |
| Aphelion | 542 AU |
| Major semi-axis | 271.6 AU |
| Sidereal period | ~ 4480 a |
| Inclination of the orbit plane | 146.4 ° |
| Perihelion | December 11, 1825 |
| Orbital velocity in the perihelion | 37.8 km / s |
| history | |
| Explorer | Jean-Louis Pons |
| Date of discovery | July 15, 1825 |
| Older name | 1825 IV |
| Source: Unless otherwise stated, the data comes from JPL Small-Body Database Browser . Please also note the note on comet articles . | |
C / 1825 N1 (Pons) was a comet that could be seen with the naked eye in 1825 . Because of its brightness and exceptionally long visibility, some count it among the " Great Comets ".
Discovery and observation
The French astronomer Jean-Louis Pons was looking for the periodic comet 2P / Encke shortly after midnight on July 15, 1825 when he discovered this new comet. Further independent discoveries were made on July 20 by Wilhelm von Biela in Austria and on July 21 by James Dunlop in Australia . At the time of its discovery, the comet was still over 2.7 AU from Earth and accordingly faint.
In the course of August the comet began to develop a tail which on August 11th was already 1.5 ° in length . From the beginning of September, the comet could be seen with the naked eye, although it was still moving outside of Mars' orbit . By the middle of the month the length of the tail had increased to 5 °.
During October the comet was brightest and best seen. Its tail reached a length of more than 10 ° and on October 12 the comet passed the earth at a distance of only 0.6 AU. For observers in high northern latitudes it was initially no longer observable, only in southern regions of the northern hemisphere for about another week, and then only in the southern hemisphere .
The comet reached its greatest southern declination at the beginning of November and was followed closely by observers in Australia and South America well into December. After passing the sun on January 9, 1826, he could not be found on board a ship in the South Pacific until February . At the beginning of April the comet appeared again in the sky for observers in the northern hemisphere, the length of the tail had meanwhile decreased to less than 1 °. In the following weeks there were only a few observations and the last one came almost a year after its discovery on July 8, 1826, when the comet was almost 3 AU away from Earth again.
The comet reached a maximum brightness of about 2-3 mag.
Effects on the zeitgeist
The 1825 comet is mentioned in the Siamese Chronicle of Luang Prabang in connection with an earthquake .
Orbit
The first calculations of the comet's orbit were carried out in 1825 by Peter Andreas Hansen , among others . In 1859 Joseph Stillman Hubbard was able to determine a limited precise elliptical orbit , which is inclined by about 164 ° to the ecliptic , from about 275 observations over a period of almost 1 year . 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 11, 1825, it was located at a distance of 185.6 million km from the sun in the area between the orbits of Earth and Mars. Already on October 12th it had reached the closest approach to the earth at a distance of about 0.62 AU / 92.4 million km. On April 14, 1827 there was a relatively close flyby at 1.27 AU / 190.6 million km distance to Jupiter .
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 1825 still had an eccentricity of about 0.9944 and a semi-major axis of about 223 AU, so that its orbit period was about 3300 years. Due to the gravitational pull of the planets, especially Jupiter when passing close by in April 1827, its orbital eccentricity was reduced to about 0.9938 and its semi-major axis to about 202 AU, so that its orbit period was shortened to about 2900 years. When it reaches the point of its orbit furthest from the sun ( aphelion ) around the year 3260 , it will be around 60 billion km away from the sun, over 400 times as far as the earth and almost 13½ times as far as Neptune . Its orbit speed in the aphelion is only about 0.11 km / s. The comet's next perihelion is expected to occur around the year 4700.
See also
Individual evidence
- ↑ GW Kronk: Cometography - A Catalog of Comets, Volume 2. 1800-1899 . Cambridge University Press, Cambridge 2003, ISBN 0-521-58505-8 , pp. 71-76.
- ^ John E. Bortle: International Comet Quarterly - The Bright-Comet Chronicles. Retrieved July 22, 2015 .
- ↑ A. Payer: Chronicle of Thailand - Chronicle 1825 (Rama III.). Retrieved July 22, 2015 .
- ↑ C / 1825 N1 (Pons) 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 .