64 Eridani

64 Eridani

A light curve for S Eridani, adapted from Koen and Eyer (2002)
Observation data
Epoch J2000      Equinox
Constellation Eridanus
Right ascension 04h 59m 55.73677s
Declination −12° 32 14.6983
Apparent magnitude (V) 4.77
Characteristics
Spectral type F0 V
B−V color index 0.266
Variable type δ Sct
Astrometry
Radial velocity (Rv)−8.9±4.2 km/s
Proper motion (μ) RA: +39.67 mas/yr
Dec.: −87.04 mas/yr
Parallax (π)12.0106±0.2199 mas
Distance272 ± 5 ly
(83 ± 2 pc)
Absolute magnitude (MV)0.03
Details
Mass1.52 M
Luminosity80.17 L
Surface gravity (log g)3.37 cgs
Temperature7,346±250 K
Rotational velocity (v sin i)212 km/s
Age644 Myr
Other designations
64 Eri, S Eri, BD−12° 1047, HD 32045, HIP 23231, HR 1611, SAO 150064
Database references
SIMBADdata

64 Eridani is a single, yellow-white hued star in the constellation Eridanus having variable star designation S Eridani. It is faintly visible to the naked eye with an apparent visual magnitude of 4.77. The annual parallax shift is measured at 12.01 mas, which equates to a distance of about 272 light years. In addition to its proper motion, it is moving closer to the Sun with a radial velocity of around −9 km/s.

This is an F-type main-sequence star with a stellar classification of F0 V. It is catalogued a low amplitude Delta Scuti variable with a primary period of 0.273 days. It was originally classified, tentatively, as an RR Lyrae variable of type 'c'.

64 Eridani is spinning rapidly with a projected rotational velocity of 212 km/s. This is giving the star an oblate shape with an equatorial bulge; its equatorial radius is 8% larger than its polar radius. The star is an estimated 644 million years old with 1.5 times the mass of the Sun. It is radiating 80 times the Sun's luminosity from its photosphere at an effective temperature of roughly 7,346 K.