Organization: Washington University, St. Louis
Date:         Wed, 27 Jan 93 14:19:08 CST
From:         Gary Kronk <C09630GK@WUVMD>
To:           NETNEWS@WUVMD
Subject:      Re: comets in 16th century
Newsgroups:   sci.astro

On January 26, 1993, O.MostynOwen@cs.ucl.ac.uk wrote:

>Please can someone help me?
Yes!

>I need to find references to the major comet sightings in the year 1506.
>Is there a compendium of such things, and if so what is it called.
There have been a few. A two volume work written in 1783 and 1784 by
Alexander Guy Pingre gives details on all comets up to 1784. It is
written in French. Books by Vsekyvatskii in 1957 and myself in 1984
did not include comets for which orbits were not computed. Yeomans
wrote a nice historical work on comets two years ago, which included
an appendix briefly detailing all comets up to 1699. This latter
book, although using my 1984 book for some details, did accurately
represent the Chinese observations of comets for which no orbits
were available, but relied heavily on Pingre for accounts from
medieval texts. The best work has not been published. I am
finishing up work on the first three volumes of Cometography and
hope to approach a publisher later this year. The first volume
will include details of all comets up to 1799, the second would
cover comets from 1800 to 1859, and the third 1860 to 1899. I
have covered all medieval documents myself and have identified
numerous errors in Pingre's work (and therefore Yeoman's). I
should also note that most of the work is also completed on
additional volumes covering comets from 1900 to the present.

>Does anyone know of ANY comet sightings in the early 16th century.
There were 52 comets seen during the entire 16th century. I have
listed below very brief details of the lone comet of 1506, as well
as one in 1502 and 1513.

1502
The Chinese found this comet on November 28, 1502, in western
Hydra. It was last seen on December 8.

1506
This comet was actually well observed in China and Japan during
the period of July 31.5 and August 14.5, 1506. It moved from
the region around Ursa Minor and Draco, then through Ursa Major,
then through the region between Gemini and Orion, and finally
wound up in the region of Coma Berenices, Leo, and Virgo. The
observations indicated the tail was becoming longer during this
period and was 5 degrees long when last seen. Orbits were
computed by Laugier (1846) and Hasegawa (1979), which indicated
perihelion dates of September 4.2 and August 28.5, respectively.
Using Hasegawa's orbit, it seems the comet was found at a solar
elongation of 71 degrees and was last seen at an elongation of
26 degrees, so that its disappearance was probably due to its
entrance into evening twilight. The comet passed closest to
Earth on August 15 (0.1425 AU) and was moving rapidly southward.

1513
Around the end of December 1513, a comet was observed in Europe
around Cancer. It was last detected on February 21, 1514, in
Virgo. The comet was apparently visible throughout the night
at one time.

>I have been asked by a historian to calculate the countries in which a comet
>would be visible given that it was visible in Britain at a particular date.
>His reference does not specify in which constellation the comet was seen in
>1506, hence my question.
Since I have yet to uncover a reference to the comet of 1506 in
European texts, I would be very interested in what this
historian found!

>Thanking you,
>Owen Mostyn-Owen                                     +44 71 387 7050 ext 3673

Sincerely,
Gary W. Kronk