7 Ceti

7 Ceti

A light curve for AE Ceti, plotted from data presented by Tabur, et al. (2009)[1]
Observation data
Epoch J2000      Equinox J2000
Constellation Cetus
Right ascension 00h 14m 38.41655s[2]
Declination −18° 55′ 58.3145″[2]
Apparent magnitude (V) 4.44[3] (4.26–4.46)[4]
Characteristics
Spectral type M1 III[5]
B−V color index 1.640±0.044[3]
Variable type LB:[4]
Astrometry
Radial velocity (Rv)−22.9±1.0[6] km/s
Proper motion (μ) RA: −26.15[2] mas/yr
Dec.: −73.58[2] mas/yr
Parallax (π)7.29 ± 0.28 mas[2]
Distance450 ± 20 ly
(137 ± 5 pc)
Absolute magnitude (MV)–1.24[3]
Details
Radius54[7] R☉
Luminosity1019.14[8] L☉
Temperature3,800[8] K
Other designations
3 Cet, AE Ceti, BD−19°21, HD 1038, HIP 1170, HR 48, SAO 147169[9]
Database references
SIMBADdata

7 Ceti is a single,[10] variable star in the equatorial constellation of Cetus. It has the variable star designation AE Ceti.[1] The star is visible to the naked eye with a baseline apparent visual magnitude of 4.44.[3] Based upon an annual parallax shift of only 7.3 mas,[2] it is located roughly 450 light years away. It is moving closer to the Sun with a heliocentric radial velocity of −23 km/s.[6] Eggen (1965) listed it as a probable member of the Wolf 630 group of co-moving stars.[11]

This is an aging red giant star with a stellar classification of M1 III,[5] currently on the asymptotic giant branch.[12] Samus et al. (2017) has it classed as a slow irregular variable of type LB:, and ranges in magnitude from 4.26 down to 4.46.[4] Tabur et al. (2009) list it as a semiregular variable with four known periods ranging in frequency from 19.2 to 41.7 days.[1] The stellar atmosphere of 7 Ceti has expanded to an estimated 54[7] times the Sun's radius. It is radiating around 1,019[8] times the Sun's luminosity from its enlarged photosphere at an effective temperature of 3,800 K.[8]

Luminosity variation[1]
Period
(Days) 		Amplitude
(Mag.)
19.2 0.018
19.6 0.020
27.1 0.018
41.7 0.017
  1. ^ a b c d Cite error: The named reference Tabur2009 was invoked but never defined (see the help page).
  2. ^ a b c d e f Cite error: The named reference vanLeeuwen2007 was invoked but never defined (see the help page).
  3. ^ a b c d Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  4. ^ a b c Cite error: The named reference Samus2017 was invoked but never defined (see the help page).
  5. ^ a b Cite error: The named reference houk1978 was invoked but never defined (see the help page).
  6. ^ a b Cite error: The named reference deBruijne2012 was invoked but never defined (see the help page).
  7. ^ a b Cite error: The named reference Fracassini2001 was invoked but never defined (see the help page).
  8. ^ a b c d Cite error: The named reference McDonald2012 was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference Eggleton2008 was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference Eggen1965 was invoked but never defined (see the help page).
  12. ^ Cite error: The named reference eggen1992 was invoked but never defined (see the help page).