A little ramble through 19th century astronomy - Mira Ceti in 1779

Nature July 6^th 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 15^th and still brighter on the 19^th; 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 25^th 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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