S Cephei Facts. If it took the Sun's place in our solar system, it would swallow the planets Mercury, Venus, Earth, Mars, Jupiter, and perhaps even Saturn, which is about 865 million miles (1.38 billion km) from the Sun. It has a period of 13 months and a diameter of between 329 to 500 solar diameters. T Cephei, also a red giant, is a Mira variable with a minimum magnitude of 11.3 and a maximum magnitude of 5.2, 685 light-years from Earth. This diagram compares the size of the Sun, which is 865,000 miles (1.38 million km) in diameter, to VV Cephei, the largest known star.

VV Cephei is 275,000-575,000 times more luminous than the Sun and is approximately 1,600–1,900 times the Sun’s diameter. The five largest known supergiants in the galaxy are red supergiants: VY Canis Majoris, Mu Cephei, KW Sagitarii, V354 Cephei, and KY Cygni. V354 Cephei Apparent and Absolute Magnitudes

VV Cephei B. VV Cephei B, the blue main sequence star, is separated from the larger star by a distance of 16 - 25 AU; it is a B0 star about 10 times the Sun's diameter and about 100,000 times its luminosity. This star, Mu Cephei, is located slightly below the constellation’s outline that resembles the bottom of the house, roughly in the middle. VV Cephei , also known as HD 208816 , is an eclipsing binary star system located in the constellation Cepheus , approximately 5,000 light years from Earth. The description is based on the spectral class. [Wikipedia] If you need the diameter of the star, you just need to multiple the radius by 2. Betelgeuse is a semiregular variable star, classified in the subgroup SRc, which also includes Mu Cephei (Herschel’s Garnet Star), RW Cygni, VX Sagittarii, and CE Tauri. The Sun's radius is 695,800km, therefore the star's radius is an estimated 1,057,616,000.00.km. The orbital period of the system is 7430 days (20.3 years). There are several prominent double stars and binary stars in Cepheus. V354 Cephei Radius. The only system with a longer period is Epsilon Aurigae (Almaaz) with a period of 9,890 days or 27.1 years. VV Cephei A The red supergiant, designated VV Cephei A, has an estimated radius between 1,050 and 1,900 times that of … Mu Cephei, also known as Herschel's Garnet Star due to its red, garnet-like color, is a red hypergiant star in the Cepheus constellation.With a radius of 1,420 solar radii, or a diameter of 1,977,000,000 kilometers, it is one of the largest stars known. It has a diameter of 1.753 billion km. Mu Cephei is also the "prototype" of … S Cephei is not part of the constellation outline but is within the borders of the constellation.