Theta Tauri

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**θ¹ Tauri**
Observation data Epoch J2000.0
Constellation (pronunciation)	Taurus
Right ascension	04^h 28^m 34.5^s
Declination	+15° 57' 44"
Apparent magnitude (V)	+3.84
Distance	153 ± 8 ly (47 ± 3 pc)
Spectral type	K0IIIbFe-0.5
Other designations
Phaeo, 77 Tauri, HR 1411, HD 28307, BD+15 631, HIP 20885, SAO 93955, GC 5433, BDS 2212, CCDM 04286+1554

**θ² Tauri**
Observation data Epoch J2000.0
Constellation (pronunciation)	Taurus
Right ascension	04^h 28^m 39.7^s
Declination	+15° 52' 15"
Apparent magnitude (V)	+3.40
Distance	155 ± 8 ly (47 ± 3 pc)
Spectral type	A7III
Other designations
Phaesyla, 78 Tauri, HR 1412, HD 28319, BD+15 632, HIP 20894, SAO 93957, GC 5436, BDS 2212, CCDM 04286+1554

Theta Tauri (θ Tau / θ Tauri) is a star system in the constellation Taurus and a member of the Hyades open cluster. It is approximately 155 light years from Earth. θ¹ Tauri has the tradiational name Phaeo (Greek Φαιω), and θ² Tauri has the traditional name Phaesyla (Greek Φαισυλα), both of which were among the seven Hyades sisters.

The system is dominated by two 3rd magnitude stars, θ¹ Tauri and θ² Tauri, which are separated by 5.62 arcminutes (0.094°) on the sky. θ¹ Tauri is the dimmer component, an orange K-type giant with an apparent magnitude of +3.84. θ² Tauri is a white A-type giant with a mean apparent magnitude of +3.40. θ² Tauri is classified as a Delta Scuti type variable star and its brightness varies from magnitude +3.35 to +3.42 with a period of 1.82 hours.

Both bright stars are spectroscopic binaries and have at least one closer companion. θ¹ Tauri has a 7th magnitude companion 0.082 arcseconds, or at least 4 Astronomical Units (AU), away from the primary. θ² has a 6th magnitude companion 0.005 arcseconds, or at least 2 AU, distant. It completes an orbit once ever 141 days.