Theta Persei
star system in the constellation Perseus
Theta Persei (Theta Per, θ Persei, θ Per) is a star system 37 light years away from Earth, in the constellation Perseus. It is one of the closest naked-eye stars.
The primary star is a yellowish dwarf (main sequence) star of spectral type F8V, which is somewhat larger and brighter than the Sun but still within the range considered to have the potential for Earth-like planets. There is also a red dwarf companion of spectral type M1.V, orbiting about 250 AU from the primary. It has a Gaia Data Release 2 parallax of 89.2871±0.1534 mas, corresponding to a distance of 11.2 pc.
An 11th-magnitude star is listed in double-star catalogs as component C of the multiple system. It was 95″ away from component A in 2002, although the separation is rapidly increasing as it is a distant background object with a very different proper motion to the other two stars. An unconfirmed companion, possibly a brown dwarf, was reported 6.2″ from θ Persei B in 2010.
References
External links
"Simbad Query Result". Simbad.
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