C / 1668 E1
| C / 1668 E1 [i] | |
|---|---|
| Properties of the orbit ( animation ) | |
| Orbit type | parabolic |
| Numerical eccentricity | 1.0 |
| Perihelion | 0.0666 AU |
| Inclination of the orbit plane | 144.4 ° |
| Perihelion | February 28, 1668 |
| Orbital velocity in the perihelion | 163 km / s |
| history | |
| Explorer | |
| Date of discovery | March 3, 1668 |
| Older name | 1668 |
| Source: Unless otherwise stated, the data comes from JPL Small-Body Database Browser . Please also note the note on comet articles . | |
C / 1668 E1 was a comet that could be seen with the naked eye in 1668 . Due to its extraordinary brightness, it is counted among the " Great Comets ".
Discovery and observation
The comet was first spotted on the evening of March 3rd at the Cape of Good Hope in South Africa . Probably only his tail could be seen over the horizon. Two days later there was an independent discovery in Lisbon , there too the head was below the horizon because of the great proximity of the sun, but the tail stretched over almost a quarter of the sky from west to east. On the same day there was an observation in Goa , India , as well as by the Jesuit Valentin Stansel in São Salvador , Brazil . It reported extraordinary brightness (you could see its reflection in the sea) and a tail length of 23 ° . He could observe the small and dark head with a telescope .
On March 7th, the comet's white glow was observed in the southwestern sky in China . Giovanni Domenico Cassini was able to see the comet for the first time on March 10th in Bologna . Two days later he reported a 32 ° long tail.
In the course of the next few days, the comet moved away from the sun and earth again and lost its brightness. A 40 ° long tail was observed in China on March 18, the last sightings of the comet were on March 21 in Goa and on March 30 in China.
The comet reached a magnitude of 1 to 2 mag on March 8th .
Superstition
In popular belief, the tail stars were harbingers of worse catastrophes, from wars and deaths to the end of the world (see fear of comets ). In the case of the comet of 1668, however, there was no other catastrophe that could be “blamed” on it than a cat death in Westphalia .
Scientific evaluation
Because of the relatively imprecise position information, Thomas James Henderson first attempted to determine the orbit elements in 1843 . He calculated two variants, one with a slightly greater perihelion distance to the sun, the second in the manner of a sungracker (sun strider). When he compared the comet's orbit in 1668 with that of the recently discovered sun streaker comet C / 1843 D1 , he assumed that the two comets were identical. While not so, Henderson was on the right track - for he was close to discovering a special family of comets .
When Heinrich Kreutz wrote his investigations into the system of comets in 1843 I, 1880 I and 1882 II between 1888 and 1901 , he was able to present evidence of a family of sun-grazing comets. Compared to Henderson, however, he had the advantage that he had the data of other comets with similar orbital elements ( C / 1880 C1 , C / 1882 R1 , C / 1887 B1 ) that could not be identical, and he looked for further candidates. The comet family he suspected with perihelia extremely close to the sun was later named the Kreutz group . The comet of 1668 may not be one of them.
Orbit
For the comet, due to the limited number of observations, only a parabolic orbit with limited precision could be determined, 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 passed on February 28, 1668, it was located at a distance of about 9.96 million km from the sun (about 14 solar radii) well within the orbit of Mercury . By February 14th it had already come close to Venus to about 38 million km and by March 4, it was approaching Earth to about 0.80 AU / 120 million km.
The comet is unlikely to return to the inner solar system , or will return many tens or hundreds of thousands of years .
See also
Individual evidence
- ^ A b Gary W. Kronk : Cometography - C / 1668 E1. Retrieved June 26, 2014 .
- ^ Donald K. Yeomans: NASA JPL Solar System Dynamics: Great Comets in History. Retrieved June 17, 2014 .
- ^ E. Hoffmann-Krayer, H. Bächtold-Stäubli: Concise Dictionary of German Superstition , Vol. 5 Part 1: Knoblauch-Matthias . De Gruyter, Berlin, 1974, ISBN 978-3110065930 , p. 90.
- ↑ C / 1668 E1 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 .