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Star in the constellation Hydrus
Epsilon Hydri , Latinized from ε Hydri, is a single,[ 8] star in the southern constellation of Hydrus . It is a faint star with an apparent visual magnitude of 4.12,[ 2] Hipparcos spacecraft showed an annual parallax shift of 21.48 mas ,[ 1] light years . The star is moving away from the Sun with a radial velocity of +13.6 km/s.[ 4] Tucana-Horologium moving group , an association of stars that share a common motion through space.[ 9]
The stellar classification for this star is B9 Va,[ 2] B-type main-sequence star that is generating energy through hydrogen fusion at its core . It is a young star, just 133[ 7] projected rotational velocity of 96 km/s.[ 5] oblate shape with an equatorial bulge that is 5% greater than the polar radius.[ 10] mass of the Sun and 2.2 times the Sun's radius .[ 5] [ 5] Sun's luminosity from its photosphere at an effective temperature of around 10,970 K.[ 7]
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