SN 185 was a
transient astronomical event
The asterisk ( ), from Late Latin , from Ancient Greek , ''asteriskos'', "little star", is a typographical symbol. It is so called because it resembles a conventional image of a heraldic star.
Computer scientists and mathematicians often voc ...
observed in the year
AD 185
Year 185 ( CLXXXV) was a common year starting on Friday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Lascivius and Atilius (or, less frequently, year 938 ''Ab urbe cond ...
, likely a
supernova
A supernova is a powerful and luminous explosion of a star. It has the plural form supernovae or supernovas, and is abbreviated SN or SNe. This transient astronomical event occurs during the last evolutionary stages of a massive star or when ...
. The transient occurred in the direction of
Alpha Centauri, between the constellations
Circinus and
Centaurus
Centaurus is a bright constellation in the southern sky. One of the largest constellations, Centaurus was included among the 48 constellations listed by the 2nd-century astronomer Ptolemy, and it remains one of the 88 modern constellations. ...
, centered at
RA Dec , in Circinus. This "
guest star
In show business, a guest appearance is the participation of an outsider performer (such as a musician or actor) in an event such as a music record or concert, show, etc., when the performer does not belong to the regular band, cast, or other ...
" was observed by
Chinese astronomers in the ''
Book of Later Han
The ''Book of the Later Han'', also known as the ''History of the Later Han'' and by its Chinese name ''Hou Hanshu'' (), is one of the Twenty-Four Histories and covers the history of the Han dynasty from 6 to 189 CE, a period known as the Later ...
'' (后汉书), and might have been recorded in
Roman
Roman or Romans most often refers to:
*Rome, the capital city of Italy
*Ancient Rome, Roman civilization from 8th century BC to 5th century AD
*Roman people, the people of ancient Rome
*''Epistle to the Romans'', shortened to ''Romans'', a letter ...
literature.
It remained visible in the night sky for eight months. This is believed to be the first supernova for which records exist.
History
''The Book of Later Han'' gives the following description:
In the 2nd year of the epoch Zhongping 平 the 10th month, on the day Guihai 亥 ecember 7, Year 185 a 'guest star
In show business, a guest appearance is the participation of an outsider performer (such as a musician or actor) in an event such as a music record or concert, show, etc., when the performer does not belong to the regular band, cast, or other ...
' appeared in the middle of the Southern Gate 門 ε_Centauri_and_Alpha_Centauri.html" "title="Epsilon_Centauri.html" ;"title="n asterism consisting of Epsilon Centauri">ε Centauri and Alpha Centauri">α Centauri
Alpha Centauri ( Latinized from α Centauri and often abbreviated Alpha Cen or α Cen) is a triple star system in the constellation of Centaurus. It consists of 3 stars: Alpha Centauri A (officially Rigil Kentaurus), Alpha Centau ...
], The size was half a bamboo mat. It displayed various colors, both pleasing and otherwise. It gradually lessened. In the 6th month of the succeeding year it disappeared.
The gaseous shell
(larger than the apparent size of the full moon, which varies from 29 to 34 arc minutes). The distance to RCW 86 is estimated to be .