Lambda Persei

Lambda Persei
Location of λ Persei (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Perseus
Right ascension 04h 06m 35.04360s[1]
Declination 50° 21′ 04.5500″[1]
Apparent magnitude (V) 4.29[2]
Characteristics
Spectral type A0IVn[3]
U−B color index −0.04[2]
B−V color index +0.02[2]
Astrometry
Radial velocity (Rv)+6.1±2.0[4] km/s
Proper motion (μ) RA: −12.75[1] mas/yr
Dec.: −35.60[1] mas/yr
Parallax (π)7.73 ± 0.22 mas[1]
Distance420 ± 10 ly
(129 ± 4 pc)
Absolute magnitude (MV)−1.31[5]
Details
Radius3.1[6] R☉
Luminosity348[5] L☉
Surface gravity (log g)4.05[7] cgs
Temperature10,585[7] K
Metallicity [Fe/H]+0.01[7] dex
Rotational velocity (v sin i)196[8] km/s
Age345[9] Myr
Other designations
λ Per, 47 Persei, BD+49°1101, FK5 1113, GC 4924, HD 25642, HIP 19167, HR 1261, SAO 24412[10]
Database references
SIMBADdata

λ Persei, Latinized as Lambda Persei, is a star in the northern constellation of Perseus. It is visible to the naked eye as a faint, white-hued point of light with an apparent visual magnitude of 4.29.[2] This object is located approximately 422 light years from the Sun based on parallax,[1] and is drifting further away with a radial velocity of +6 km/s.[4]

λ Persei in optical light

This object has a stellar classification of A0IVn,[3] matching an A-type subgiant star with "nebulous" lines due to rapid rotation. It is spinning with a projected rotational velocity of 196 km/s,[8] which is giving the star an equatorial bulge that is an estimated 16% larger than the polar radius.[11] Unusually for a star of this type, spectra show weak emission features among the Hydrogen lines, which may be due to plage regions on the surface caused by an implied magnetic field.[12] The star is 345[9] million years old and is radiating 348[5] times the luminosity of the Sun from its photosphere at an effective temperature of 10,585 K.[7]

In Chinese astronomy, Lambda Persei is called 積水, Pinyin: Jīshuǐ, meaning Stored Water, because this star is marking itself and stand alone in Stored Water asterism, Stomach mansion (see : Chinese constellation).[13]

  1. ^ a b c d e f Cite error: The named reference vanLeeuwen2007 was invoked but never defined (see the help page).
  2. ^ a b c d Cite error: The named reference Ducati2002 was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference Cowley1969 was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference Wilson1953 was invoked but never defined (see the help page).
  5. ^ a b c Cite error: The named reference XHIP was invoked but never defined (see the help page).
  6. ^ Cite error: The named reference Fracassini2001 was invoked but never defined (see the help page).
  7. ^ a b c d Cite error: The named reference Wu2011 was invoked but never defined (see the help page).
  8. ^ a b Cite error: The named reference Hoffleit1991 was invoked but never defined (see the help page).
  9. ^ a b Cite error: The named reference Gontcharov2012 was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference belle2012 was invoked but never defined (see the help page).
  12. ^ Cite error: The named reference Underhill1991 was invoked but never defined (see the help page).
  13. ^ (in Chinese) AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 7 月 11 日