C / 400 F1 - C/400 F1
|C / 400 F1 [i]|
|Properties of the orbit ( animation )|
|Perihelion||0,21 ± 0,1 AE|
|Inclination of the orbit plane||32 ± 5°|
|Periheldurchgang||February 25, 400 ± 3 days|
|Railway speed in the perihelion||92 ± 22 km / s|
|Date of discovery||March 18, 400|
|Source: Unless otherwise stated, the data comes from JPL Small-Body Database Browser . Please also note the note on comet articles .|
Discovery and observation
The Chinese chronicle Chén Shū from the 7th century reports that a "sparkling star" was first sighted on the morning of March 19, 400 (local time), which was in the constellation Andromeda and already had a north-pointing tail of 30 ° longitude. A Korean chronicle in Samguk Sagi also reports a “twinkling star” that appeared sometime in spring between around mid-March and mid-April.
The Chén Shū also reports that the comet initially moved north in the sky to the vicinity of the Big Dipper and then moved south again towards the end of March. He was most likely last seen in the constellation Virgo in mid-April .   The Chinese chronicle Wèi Shū from the 6th century contains essentially the same information, but gives the date of the first sighting a month later than the Chén Shū .
While the Chinese accounts do not necessarily report an exceptionally bright comet, there is reason to believe that it was.  Because there are also several European sources that report a large comet in the year 400. The Eastern Roman historian Philostorgios tells about 25 years after the event in his Ekklesiastike Historia of the appearance of a "sword-shaped star" that heralded a misfortune.
Similarly, a few years later, the historian Socrates Scholastikos reported in his Ekklesiastike historia and in similar words the Roman historian and lawyer Sozomenos in his Historia Ecclesiastica of the appearance of a “comet of immense size” in the year 400. During the attack by Gainas on Constantinople was “his Company announced by the appearance of a comet directly over town ”. This comet was "of extraordinary size, larger, it was said, than any seen before, and reached almost to Earth." 
Hasegawa could only determine a very uncertain parabolic orbit for the comet from observations over 22 days ,  which is inclined by around 32 ° to the ecliptic .  At the point of the orbit closest to the sun ( perihelion ), which the comet would have traversed around February 25, 400, it was located at a distance of around 31 million km from the sun, far within the orbit of Mercury . By February 7th, it would have come close to Venus to about 46 million km, and by March 31st, it could be close to Earth to about 0.075 AU/ 11 million km.  This could explain its great brightness and thus it would be one of the 20 closest comets to earth in historical time. 
Due to the uncertain initial data, no statement can be made as to whether and, if so, when the comet could return to the inner solar system .
- AG Pingré: Cometography or Historical and Theoretical Treatise on Comets. Tome I. Imprimerie Royale, Paris 1783, S. 306–307, 598 ( PDF; 56.49 MB ).
- J. Williams: Observations of Comets, from B.C. 611 to A.D. 1640. Strangeways and Walden, London 1871, S. 30 (PDF, 20,93 MB).
- D. A. J. Seargent: The Greatest Comets in History: Broom Stars and Celestial Scimitars. Springer, New York 2009, ISBN 978-0-387-09512-7, S. 79–80.
- G. W. Kronk: Cometography – A Catalog of Comets, Volume 1, Ancient–1799. Cambridge University Press, Cambridge 1999, ISBN 978-0-521-58504-0, S. 71–72.
- D. K. Yeomans: NASA JPL Solar System Dynamics: Great Comets in History. Abgerufen am 27. Juni 2016 (englisch).
- I. Hasegawa: Orbits of Ancient and Medieval Comets. In: Publications of the Astronomical Society of Japan. Vol. 31, 1979, S. 257–270 (bibcode:1979PASJ...31..257H).
- C/400 F1 in der Small-Body Database des Jet Propulsion Laboratory (englisch).
- A. Vitagliano: SOLEX 11.0. Archived from the original on September 18, 2015 ; accessed on May 2, 2014 .
- Historic Comet Close Approaches Prior to 2006. NASA, accessed June 24, 2016 .