39 Tauri

39 Tauri is the Flamsteed designation for an unresolved binary star in the northern constellation of Taurus. It has an apparent visual magnitude of 5.90, so, according to the Bortle scale, it is faintly visible from suburban skies at night. Measurements made with the Hipparcos spacecraft show an annual parallax shift of 0.05904″, which is equivalent to a distance of around 55.2 ly (16.9 pc) from the Sun.

A stellar classification of G5 V matches that of a G-type main sequence star; the type of the secondary component is unknown. Stellar models indicate the primary component is similar in physical properties to the Sun, with 110% of the Sun's mass, 96% of the radius, and shining with almost the same luminosity. The overall metallicity of the star—the abundance of elements other than hydrogen and helium—is similar to the Sun. At a relatively youthful estimated age of one billion years, it is rotating with a period of 9.12 days. Based upon Hipparcos data, it displays a mild variability with an amplitude of 0.06 magnitude.

Tauri

The Tauri (/ˈtaʊəri/; Ταῦροι in Ancient Greek), also Scythotauri, Tauri Scythae, Tauroscythae (Pliny, H. N. 4.85) were a people settled on the southern coast of the Crimea peninsula, inhabiting the Crimean Mountains and the narrow strip of land between the mountains and the Black Sea. They gave their name to the peninsula, which was known in ancient times as Taurica, Taurida and Tauris.

In his Histories, Herodotus describes the Tauri as living "by plundering and war". They became famous for their worship of a virgin goddess, to whom they sacrificed shipwrecked travellers and waylaid Greeks. He makes a point of them living in Scythia geographically without themselves being Scythians. In Geographica, Strabo refers to the Tauri as a Scythian tribe.

The Greeks identified the Tauric goddess with Artemis Tauropolos or with Iphigeneia, daughter of Agamemnon. The Tauric custom of human sacrifice inspired the Greek legends of Iphigeneia and Orestes, recounted in Iphigeneia in Tauris by the playwright Euripides.

Zeta Tauri

Zeta Tauri (ζ Tau, ζ Tauri, Shurnarkabti-sha-shūtū) is a binary star in the zodiac constellation Taurus, the Bull. It has an apparent visual magnitude of 3.0, which is bright enough to be seen with the naked eye. Parallax measurements place it at a distance of roughly 440 light-years from the Earth.

In Chinese astronomy, Zeta Tauri is called 天關, Pinyin: Tiānguān, meaning Celestial Gate, an asterism within the Net (畢宿 Bì Xiù) mansion (see also: Chinese constellation). 天關 (Tiānguān) has also been transliterated as Tien Kwan. Technically, Tiānguān refers not just to Zeta Tauri but to an asterism of which Zeta Tauri is the main star, alongside 113 Tau, 126 Tau, 128 Tau, 129 Tau, 130 Tau and 127 Tau (see Taurus (Chinese astronomy)).

Properties

This is a single-lined spectroscopic binary system, which means the two components are orbiting so close to each other that they can not be resolved with a telescope. Instead, the orbital motion of the primary component is indicated by Doppler effect shifts in the absorption lines in its spectrum. The two components are separated by an estimated distance of about 1.17 Astronomical Units, or 117% of the distance from the Earth to the Sun. They are following circular orbits with a period of nearly 133 days.

Celaeno (star)

Celaeno (Celeno or 16 Tauri) is a star in the constellation Taurus and a member of the Pleiades open cluster of stars. Celaeno has been called the "Lost Pleiad" by Theon the Younger.

16 Tauri is a blue-white B-type subgiant with an apparent magnitude of +5.45. It is approximately 430 light years from Earth; about the same distance as the Pleiades. The interstellar extinction of this star is fairly small at 0.05 magnitudes. The projected rotational velocity of the equator is 185 km/s. It is over four times the radius of the Sun and has a surface temperature of 12,800 K.

Namesakes

USS Celeno (AK-76) was a United States Navy Crater class cargo ship named after the star.

References