24 Ursae Majoris

24 Ursae Majoris
	; A light curve for DK Ursae Majoris, plotted from Hipparcos data
Observation data; Epoch J2000 Equinox J2000
Constellation	Ursa Major
Right ascension	09h 34m 28.86175s
Declination	+69° 49′ 49.2265″
Apparent magnitude (V)	4.54
Characteristics
Spectral type	G4 III-IV
B−V color index	0.781±0.011
Variable type	RS CVn
Astrometry
Radial velocity (Rv)	−27.0±0.2 km/s
Proper motion (μ)	RA: −64.785 mas/yr ; Dec.: +77.214 mas/yr
Parallax (π)	30.9269 ± 0.1621 mas
Distance	105.5 ± 0.6 ly ; (32.3 ± 0.2 pc)
Absolute magnitude (MV)	2.16±0.013
Details
Mass	1.9 M☉
Radius	4.6 R☉
Luminosity	14.9 L☉
Surface gravity (log g)	3.44 cgs
Temperature	5,335 K
Metallicity [Fe/H]	−0.19 dex
Rotation	10 d
Rotational velocity (v sin i)	5.5 km/s
Age	1.0±0.1 Gyr
Other designations
	d UMa, 24 UMa, DK UMa, BD+70°565, FK5 357, HD 82210, HIP 46977, HR 3771, SAO 6897
Database references
SIMBAD	data

24 Ursae Majoris is a variable star in the northern circumpolar constellation of Ursa Major, located 101.5 light-years from the Sun.^[2] It has the variable star designation DK Ursae Majoris and the Bayer designation d Ursae Majoris; 24 Ursae Majoris is the Flamsteed designation. This object is visible to the naked eye as a faint, yellow-hued star with an apparent visual magnitude of 4.54.^[3] It is moving closer to the Earth with a heliocentric radial velocity of −27 km/s, and is expected to come as close as 51 light-years in around 879,000 years.^{[failed verification]}^[3]

^ Cite error: The named reference CDS was invoked but never defined (see the help page).
^ ^a ^b ^c ^d ^e ^f Cite error: The named reference GaiaDR2 was invoked but never defined (see the help page).
^ ^a ^b ^c ^d ^e Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
^ Cite error: The named reference Keenan1989 was invoked but never defined (see the help page).
^ Cite error: The named reference Samus2017 was invoked but never defined (see the help page).
^ ^a ^b ^c ^d Cite error: The named reference park2013 was invoked but never defined (see the help page).
^ ^a ^b ^c ^d Cite error: The named reference Gondoin2005 was invoked but never defined (see the help page).
^ Cite error: The named reference Ayres2007 was invoked but never defined (see the help page).
^ Cite error: The named reference Pace2013 was invoked but never defined (see the help page).
^ Cite error: The named reference Simbad was invoked but never defined (see the help page).

Observation data Epoch J2000 Equinox J2000
A light curve for DK Ursae Majoris, plotted from Hipparcos data^[1]
Constellation	Ursa Major
Right ascension	09^h 34^m 28.86175^s^[2]
Declination	+69° 49′ 49.2265″^[2]
Apparent magnitude (V)	4.54^[3]
Characteristics
Spectral type	G4 III-IV^[4]
B−V color index	0.781±0.011^[3]
Variable type	RS CVn^[5]
Astrometry

Radial velocity (R_v)	−27.0±0.2^[3] km/s
Proper motion (μ)	RA: −64.785^[2] mas/yr Dec.: +77.214^[2] mas/yr
Parallax (π)	30.9269 ± 0.1621 mas^[2]
Distance	105.5 ± 0.6 ly (32.3 ± 0.2 pc)
Absolute magnitude (M_V)	2.16±0.013^[6]

Details

Mass	1.9^[7] `M`_☉
Radius	4.6^[7] `R`_☉
Luminosity	14.9^[7] `L`_☉
Surface gravity (log g)	3.44^[6] cgs
Temperature	5,335^[6] K
Metallicity [Fe/H]	−0.19^[6] dex
Rotation	10 d^[7]
Rotational velocity (v sin i)	5.5^[8] km/s
Age	1.0±0.1^[9] Gyr

Other designations
d UMa, 24 UMa, DK UMa, BD+70°565, FK5 357, HD 82210, HIP 46977, HR 3771, SAO 6897^[10]
Database references
SIMBAD	data