Iota Cancri

ι Cancri
Location of ι Cancri (circled)
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Cancer
ι Cnc A
Right ascension 08h 46m 41.820s
Declination +28° 45′ 35.62″
Apparent magnitude (V) 4.03
ι Cnc B
Right ascension 08h 46m 39.980s
Declination +28° 45′ 54.21″
Apparent magnitude (V) 6.58
Characteristics
ι Cnc A
Spectral type G8IIIa Ba0.2
B−V color index 1.007±0.015
ι Cnc B
Evolutionary stage main sequence
Spectral type A2V
B−V color index 0.051±0.008
Astrometry
ι Cnc A
Radial velocity (Rv)15.74±0.13 km/s
Proper motion (μ) RA: −22.070 mas/yr
Dec.: −43.699 mas/yr
Parallax (π)9.4124±0.1621 mas
Distance347 ± 6 ly
(106 ± 2 pc)
Absolute magnitude (MV)−0.79
ι Cnc B
Radial velocity (Rv)25.00±1.5 km/s
Proper motion (μ) RA: −24.397 mas/yr
Dec.: −44.250 mas/yr
Parallax (π)9.6720±0.0362 mas
Distance337 ± 1 ly
(103.4 ± 0.4 pc)
Details
ι Cnc A
Mass2.376±0.011 M
Radius21 R
Luminosity204 L
Surface gravity (log g)2.5 cgs
Temperature4,954 K
Metallicity [Fe/H]−0.14 dex
ι Cnc B
Mass2.113±0.035 M
Radius1.94±0.05 R
Luminosity24.9±1.2 L
Surface gravity (log g)4.23±0.06 cgs
Temperature9,259±139 K
Rotational velocity (v sin i)170 km/s
Age263 Myr
Other designations
ι Cancri, 48 Cancri, WDS J08467+2846
Iota Cancri A: Yuyu, NSV 4238, BD+29°1824, FK5 328, GC 12083, HD 74739, HIP 43103, HR 3475, SAO 80416
Iota Cancri B: BD+29°1823, GC 12080, HD 74738, HIP 43100, HR 3474, SAO 80415, TIC 117355623
Database references
SIMBADA
B

Iota Cancri, also named Yuyu, is a double star in the constellation Cancer. The brighter component is located at a distance of approximately 347 light-years (106 pc) from Earth based on parallax measurements, and is drifting further away with a line of sight velocity of 16 km/s.

The two stars of ι Cancri are separated by 30.5 arcseconds as of 2019, corresponding to a projected separation of 3,236 AU (0.05 ly). Although no orbit has been derived, the pair show a large common proper motion and are assumed to be gravitationally related.