ζ Hydri
02h45m 32.63435s[1]
−67° 36′ 59.8268″[1]
4.83[2]
Characteristics
A2IV[2]
U−B color index
+0.09[3]
B−V color index
+0.06[3]
Radial velocity (Rv)
+3.60[4] km/s
Proper motion (μ)
RA: +66.41[1] mas/yr
Dec.: +43.38[1] mas/yr
Parallax (π)
Absolute magnitude (MV)
0.13[2]
Details
Surface gravity (log g)
Rotational velocity (v sin i)
116[6] km/s
Database references
Zeta Hydri, Latinized from ζ Hydri, is a single,[7] white-hued star in the southern constellationofHydrus. It is faintly visible to the naked eye with an apparent magnitude of 4.83.[2] This distance to this star can be estimated from its annual parallax shift of 11.47 mas,[1] showing it to be about 284 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] suggesting it is a 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] This is giving the star a slight oblate shape with an equatorial bulge that is 5% larger than the polar radius.[8] It has 2.4 times the mass of the Sun and nearly four times the Sun's radius.[5] Zeta Hydri is radiating 80[2] times the Sun's luminosity into space from its photosphere at an effective temperature of 9,144 K.[6]
Other
Other
