HAT-P-4

HAT-P-4
Observation data
Epoch J2000      Equinox J2000
Constellation Boötes
HAT-P-4A
Right ascension 15h 19m 57.9204s
Declination +36° 13 46.738
Apparent magnitude (V) 11.159±0.010
HAT-P-4B
Right ascension 15h 20m 00.0127s
Declination +36° 12 18.520
Apparent magnitude (V) 11.534±0.01
Characteristics
HAT-P-4A
Spectral type G0V
B−V color index 0.771
Variable type planetary transit
HAT-P-4B
Spectral type G2V
Astrometry
HAT-P-4A
Radial velocity (Rv)−1.13(37) km/s
Proper motion (μ) RA: −21.513(13) mas/yr
Dec.: −24.255(19) mas/yr
Parallax (π)3.1071±0.0154 mas
Distance1,050 ± 5 ly
(322 ± 2 pc)
HAT-P-4B
Radial velocity (Rv)−1.31(35) km/s
Proper motion (μ) RA: −21.424(13) mas/yr
Dec.: −24.182(20) mas/yr
Parallax (π)3.0777 ± 0.0155 mas
Distance1,060 ± 5 ly
(325 ± 2 pc)
Position (relative to HAT-P-4A)
ComponentHAT-P-4B
Epoch of observation1999/02/07
Angular distance91.760±0.099
Position angle163.97±0.06°
Projected separation28446 AU
Details
HAT-P-4A
Mass1.260+0.043
0.042
 M
Radius1.573±0.015 R
Luminosity2.8 L
Surface gravity (log g)4.145±0.015 cgs
Temperature5927+57
47
 K
Metallicity [Fe/H]0.277±0.007 dex
Rotational velocity (v sin i)5.6 ± 0.9 km/s
Age~4.2 Gyr
HAT-P-4B
Mass1.0 M
Radius1.3 R
Luminosity2.0 L
Surface gravity (log g)4.38±0.14 cgs
Temperature6037±37 K
Metallicity [Fe/H]0.175±0.006 dex
Age7.8 Gyr
Other designations
HAT-P-4A: BD+36°2593, SAO 64638, TYC 2569-1599-1, GSC 02569-01599, 2MASS J15195792+3613467
HAT-P-4B: TYC 2569-744-1, 2MASS J15200001+3612185
Database references
SIMBADA
B
Data sources:
Hipparcos Catalogue,
CCDM (2002),
Bright Star Catalogue (5th rev. ed.)

HAT-P-4 is a wide binary star consisting of a pair of G-type main-sequence stars in the constellation of Boötes. It also has the BD designation BD+36°2593.

The star exhibits an infrared excess of unknown origin.