47 Capricorni

This article is about c2 Capricorni. For other stars with this Bayer designation, see c Capricorni.
47 Capricorni

A light curve for AG Capricorni, plotted from Hipparcos data[1]
Observation data
Epoch J2000      Equinox J2000
Constellation Capricornus
Right ascension 21h 46m 16.26887s[2]
Declination −09° 16′ 33.3799″[2]
Apparent magnitude (V) 6.00[3] (5.90 - 6.14)[4]
Characteristics
Evolutionary stage giant
Spectral type M2III[5]
B−V color index 1.629±0.010[3]
Variable type SRb[4]
Astrometry
Radial velocity (Rv)+19.80±0.89[6] km/s
Proper motion (μ) RA: +18.731[2] mas/yr
Dec.: +8.387[2] mas/yr
Parallax (π)2.7933 ± 0.2052 mas[2]
Distance1,170 ± 90 ly
(360 ± 30 pc)
Absolute magnitude (MV)−1.76[3]
Details
Radius102+11
−10[2] R☉
Luminosity1,940±162[2] L☉
Temperature3,784+188
−186[2] K
Other designations
c2 Cap, 47 Cap, AG Cap, BD−09°5833, HD 207005, HIP 107487, HR 8318, SAO 145648[7]
Database references
SIMBADdata

47 Capricorni is a variable star located around 1,170[2] light years from the Sun in the southern constellation Capricornus,[7] near the northern border with Aquarius. It has the variable star designation of AG Capricorni and a Bayer designation of c2 Capricorni;[8] 47 Capricorni is the Flamsteed designation. This object is visible to the naked eye as a dim, red-hued point of light with an apparent visual magnitude that varies between 5.90 and 6.14. The star is receding from the Earth with a heliocentric radial velocity of +20 km/s.[6]

This is an aging red giant star with a stellar classification of M2III.[5] It is a semiregular variable star of subtype SRb with a period of 30.592 days and a maximum brightness of 5.9 magnitude.[4] With the supply of hydrogen at its core exhausted, the star has expanded to around 102[2] times the Sun's radius. It is radiating 1,940[2] times the luminosity of the Sun from its swollen photosphere at an effective temperature of 3,784 K.[2]

  1. ^ Cite error: The named reference HipDataAccess was invoked but never defined (see the help page).
  2. ^ a b c d e f g h i j k l Cite error: The named reference GaiaDR2 was invoked but never defined (see the help page).
  3. ^ a b c Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  4. ^ a b c Cite error: The named reference gcvs was invoked but never defined (see the help page).
  5. ^ a b Cite error: The named reference mk was invoked but never defined (see the help page).
  6. ^ a b Cite error: The named reference rv was invoked but never defined (see the help page).
  7. ^ a b Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  8. ^ Cite error: The named reference Koostjuk2002 was invoked but never defined (see the help page).