Star in the constellation Hydrus
Zeta Hydri , Latinized from ζ Hydri, is a single,[ 7] star in the southern constellation of Hydrus . It is faintly visible to the naked eye with an apparent magnitude of 4.83.[ 2] parallax shift of 11.47 mas ,[ 1] light years away. It is moving further away from the Sun with a radial velocity of +3.6 km/s.[ 4]
The spectrum of this star matches a stellar classification of A2 IV,[ 2] subgiant star that is in the process of evolving away from the main sequence as the supply of hydrogen at its core becomes exhausted. It has a high rate of spin, showing a projected rotational velocity of 116 km/s.[ 6] oblate shape with an equatorial bulge that is 5% larger than the polar radius.[ 8] mass of the Sun and nearly four times the Sun's radius .[ 5] [ 2] Sun's luminosity into space from its photosphere at an effective temperature of 9,144 K.[ 6]
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