Binary star system in the constellation Hydra
For other stars with this Bayer designation, see
τ Hydrae .
Tau2 Hydrae is a probableastrometric binary [ 10] constellation ofHydra . Based upon an annualparallax shift of 6.30 mas as seen from Earth, it is located around 520 light years from theSun . The brighter component is visible to the naked eye with anapparent visual magnitude of +4.56.[ 2]
The primary member, component A, is anA-type main sequence star with astellar classification of A3 V.[ 3] suspected variable of unknown type, with anamplitude of 0.06 in visual magnitude.[ 4] [ 7] radius of the Sun and is radiating about 285 times thesolar luminosity from itsphotosphere at aneffective temperature of 7,918 K.[ 8]
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