How far away are Mu Cephi and VV Cephi, and what are their other stats?

They are both M2, type Ia supergiants with effective photospheric temperatures near 3500 K give or take 100 K.

Mu Cepi is a variable star with periods of 700 - 900 days, and there is also apparently a 13.5 years period too. Complicated! Its visual magnitude range is from +3.4 to + 5.1 with a mean visual magnitude of +4.0.

VV Cepi is also a variable star with a 7430 day period, but it is listed as also being a spectrum variable, shifting from M2 Ia to M2 Iab during its cycle which means a temperature change is also happening. The apparent visual magnitude changes from +4.8 to +5.3 with a mean value near +5.0.

As for their distances, I can't find a published value in a quick search, but the tables of absolute visual magnitudes give M2 Ia supergiants as Mv = -6.9m. From their apparent visual magnitudes of +4.0 and +5.0 respectively, and assuming no funny business with interstellar absorption or intrinsic absorption due to circumstellar dust, you get from

M = m + 5 - 5 log(dpc)
that
d(Mu Cep) = 1,500 parsecs or 4,900 light years
d(VV Cep)  = 2,400 parsecs or 7,700 light years.

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