Nature July 6th 1876
Mira Ceti
Reference is often made in treatises on astronomy to the
unusual degree of brilliancy attained by this variable star at the maximum of
1779.
From the observations of Bode, Herschel and Wargentin, we
have the following particulars of the augmentation and diminution of brightness
in that year.
Aug 22 – Invisible in an ordinary 2 feet telescope
Sept 8 – Seen with the same instrument but very faint
Sept 18 Immediately visible to the naked eye according to
Herschel. Bode estimated it magnitude 4
Oct 5 and Oct 6 – Already much brighter than Menkar (alpha
Ceti)
Oct 15- Oct 19 – Equal to alpha Arietis on the 15th
and still brighter on the 19th; the light reddish
Oct 30 – According to Wargentin, it was equal to Aldebaran
and of the same colour, or even of the redness of Mars which was observable the
same night. In a 10 feet achromatic Mira shot out vivid red rays. Herschel
considered it midway in brightness between alpha Arietis and Aldebaran.
Nov 2 – There was even an increase, in the judgement of
Herschel
Nov 11 – Visible as early as Aldebaran and Mars
Nov 20 – As bright as, but not brighter than stars of the
second magnitude, according to Herschel, but on the 25th much
brighter than Menkar, though less than Aldebaran according to Wargentin
Dec 4 – Only equal to alpha Arietis
Dec 7 and Dec 10 – So much diminished since November 25,
that it was now hardly equal to Menkar, and its colour was now whiter.
Dec 25 – Before the Moon rose equal to gamma Ceti, or of the
third magnitude
Dec 29 – Only a little brighter than the fourth magnitude;
not equal to gamma or delta Ceti
Argelander gives for the date of maximum Nov 6 1779
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