HR 1170
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  | |
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Perseus |
| Right ascension | 03h 49m 08.10977s[1] |
| Declination | +43° 57′ 47.3016″[1] |
| Apparent magnitude (V) | 5.77 - 5.91[2] |
| Characteristics | |
| Spectral type | A9IV[3] |
| U−B color index | 0.06[4] |
| B−V color index | 0.26[4] |
| Variable type | Delta Scuti[2] |
| Astrometry | |
| Radial velocity (Rv) | −11.1±2.6[5] km/s |
| Proper motion (μ) | RA: −3.453±0.244[1] mas/yr Dec.: 11.469±0.200[1] mas/yr |
| Parallax (π) | 14.6959±0.2134 mas[1] |
| Distance | 222 ± 3 ly (68.0 ± 1.0 pc) |
| Absolute magnitude (MV) | 1.73±0.07[6] |
| Details | |
| Mass | 1.98±0.04[7] M☉ |
| Radius | 2.7[1] R☉ |
| Luminosity | 23±2[7] L☉ |
| Surface gravity (log g) | 3.77[1] cgs |
| Temperature | 7194±50[8] K |
| Metallicity [Fe/H] | 0.30[3] dex |
| Rotational velocity (v sin i) | 103[7] km/s |
| Age | 1.12[1] Gyr |
| Other designations | |
| V376 Per, HD 23728, HIP 17846, SAO 39128[9] | |
| Database references | |
| SIMBAD | data |
HR 1170, also known as HD 23728 and V376 Persei, is a star about 220 light years from the Earth, in the constellation Perseus.[1] It is a 5th magnitude star, so it will be faintly visible to the naked eye of an observer far from city lights. It is a variable star, whose brightness varies slightly from magnitude 5.77 to 5.91.[2]
Michel Breger announced that HR 1170 is a Delta Scuti variable star in 1969, based on observations taken over 6 hours and 10 minutes on October 13, 1967. He reported that it varied with a mean amplitude of 0.08 magnitudes, over a period of 2.2 hours.[11] In 1970 it was given the variable star designation V376 Persei.[12]
Early investigations of HR 1170 showed that it has more than one pulsation period,[13] as is true for most Delta Scuti stars,[14] and the light curve shows the different periods beating with each other. Many investigators have tried to determine the modes of oscillation present in this star.[15][16][17][18][19][20][21] All but one[19] of these studies find only two significant periods. All agree that one of the periods is approximately 2.386 hours, but the studies do not agree on the second period.[21] There is also no agreement as to whether the pulsations are radial, nonradial or a combination of the two, though most of the later studies, which examine data taken over a longer time window, conclude that at least one of the pulsation modes is nonradial.
