Article · Wikipedia archive · Last revised Aug 9, 2026

ADS 16402

ADS 16402 is a binary star system, composed of two sun-like stars located approximately 525 light-years away in the constellation Lacerta. It was first identified as a binary star by John Herschel in 1831. The two stars are separated by 11.26 arcseconds which leads to a projected separation of roughly 1500 astronomical units at the distance of ADS 16402. The star system is estimated to be 1.9 ± 0.6 billion years old. The secondary star ADS 16402 B is also designated HAT-P-1.

Last revised
Aug 9, 2026
Read time
≈ 4 min
Length
808 w
Citations
55
Source
ADS 16402
Observation data
Epoch J2000.0      Equinox ICRS
Constellation Lacerta1
ADS 16402 A
Right ascension 22h 57m 45.9211s2
Declination +38° 40′ 27.200″2
Apparent magnitude (V) +10.03
ADS 16402 B (HAT-P-1)
Right ascension 22h 57m 46.8442s4
Declination +38° 40′ 30.358″4
Apparent magnitude (V) +10.43
Characteristics
ADS 16402 A
Spectral type F83/G0V5
Apparent magnitude (J) 8.670±0.0216
Apparent magnitude (H) 8.467±0.0446
Apparent magnitude (K) 8.405±0.0206
ADS 16402 B (HAT-P-1)
Spectral type F83/G0V5
Apparent magnitude (J) 9.156±0.0266
Apparent magnitude (H) 8.923±0.0306
Apparent magnitude (K) 8.858±0.0186
Variable type planetary transit5
Astrometry
ADS 16402 A
Radial velocity (Rv)−3.43 ± 0.325 km/s
Proper motion (μ) RA: 32.079(15) mas/yr2
Dec.: −42.076(18) mas/yr2
Parallax (π)6.2364±0.0164 mas2
Distance523 ± 1 ly
(160.3 ± 0.4 pc)
Absolute magnitude (MV)3.4 ± 0.35
ADS 16402 B (HAT-P-1)
Radial velocity (Rv)−2.94 ± 0.565 km/s
Proper motion (μ) RA: 32.422(14) mas/yr4
Dec.: −41.949(13) mas/yr4
Parallax (π)6.2438±0.0146 mas4
Distance522 ± 1 ly
(160.2 ± 0.4 pc)
Absolute magnitude (MV)3.7 ± 0.35
Details
ADS 16402 A
Mass1.16 ± 0.115 M
Radius1.123 +0.14
−0.10
5 R
Luminosity1.82 +0.75
−0.53
5 L
Surface gravity (log g)4.36 ± 0.037 cgs
Temperature6251 ± 177 K
Metallicity [Fe/H]0.146 ± 0.0147 dex
Rotational velocity (v sin i)7.1 ± 0.35 km/s
Age1.9 ± 0.68 Gyr
ADS 16402 B (HAT-P-1)
Mass1.151 +0.052
−0.051
9 M
Radius1.174 +0.026
−0.027
9 R
Luminosity1.585 +0.099
−0.094
9 L
Surface gravity (log g)4.43 ± 0.027 cgs
Temperature6049 ± 87 K
Metallicity [Fe/H]0.155 ± 0.0077 dex
Rotational velocity (v sin i)2.2 ± 0.25 km/s
Age1.9 ± 0.68 Gyr
Position (relative to ADS 16402 A)
Angular distance11.26 ± 0.03 10
Other designations
BD+37°4734, CCDM J22578+3840, WDS J22578+3840, HJ 18321112
ADS 16402 A: PPM 88381, 2MASS J22574592+3840272, Gaia DR3 192843176462766131211
ADS 16402 B: HAT-P-1, PPM 88382, 2MASS J22574684+3840302, Gaia DR3 192843176462766144012
Database references
SIMBADADS 16402
ADS 16402 A
HAT-P-1

ADS 16402 is a binary star system, composed of two sun-like stars located approximately 525 light-years away in the constellation Lacerta. It was first identified as a binary star by John Herschel in 1831.5 The two stars are separated by 11.26 arcseconds which leads to a projected separation of roughly 1500 astronomical units at the distance of ADS 16402. The star system is estimated to be 1.9 ± 0.6 billion years old.8 The secondary star ADS 16402 B is also designated HAT-P-1.

Planetary system

On September 14, 2006 the HATNet Project announced their first extrasolar planet discovery HAT-P-1b, a hot jupiter type gas giant in orbit around the secondary star ADS 16402B. Following the designation scheme used by the HATNet Project, the secondary star is known as HAT-P-1, and the planet itself designated HAT-P-1b.513

The HAT-P-1 planetary system149
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity Inclination
(°)
Radius
b 0.529 ± 0.020 MJ 0.05561 ± 0.00083 4.4652968 ± 0.0000018 0 85.634 ± 0.056 1.319 ± 0.019 RJ
See also

See also

References

References

  1. Roman, Nancy G. (1987). "Identification of a constellation from a position". Publications of the Astronomical Society of the Pacific. 99 (617): 695. Bibcode:1987PASP...99..695R. doi:10.1086/132034. Constellation record for this object at VizieR.
  2. Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
  3. "ADS16402". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2009-05-10.
  4. Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
  5. Bakos, G. Á.; et al. (2007). "HAT-P-1b: A Large-Radius, Low-Density Exoplanet Transiting One Member of a Stellar Binary". The Astrophysical Journal. 656 (1): 552–559. arXiv:astro-ph/0609369. Bibcode:2007ApJ...656..552B. doi:10.1086/509874.
  6. Skrutskie, M. F.; et al. (2006). "The Two Micron All Sky Survey (2MASS)". The Astronomical Journal. 131 (2): 1163–1183. Bibcode:2006AJ....131.1163S. doi:10.1086/498708. Vizier catalog entry for A Vizier catalog entry for B
  7. Liu, F.; et al. (2014). "A high-precision chemical abundance analysis of the HAT-P-1 stellar binary: constraints on planet formation". Monthly Notices of the Royal Astronomical Society. 442 (1): L51–L55. arXiv:1404.2112. Bibcode:2014MNRAS.442L..51L. doi:10.1093/mnrasl/slu055.
  8. Bonfanti, A.; et al. (2015). "Revising the ages of planet-hosting stars". Astronomy and Astrophysics. 575 A18. arXiv:1411.4302. Bibcode:2015A&A...575A..18B. doi:10.1051/0004-6361/201424951.
  9. Nikolov, N.; et al. (2014). "Hubble Space Telescope hot Jupiter transmission spectral survey: a detection of Na and strong optical absorption in HAT-P-1b". Monthly Notices of the Royal Astronomical Society. 437 (1): 46–66. arXiv:1310.0083. Bibcode:2014MNRAS.437...46N. doi:10.1093/mnras/stt1859.
  10. Faedi, F.; et al. (2013). "Lucky imaging of transiting planet host stars with LuckyCam". Monthly Notices of the Royal Astronomical Society. 433 (3): 2097–2106. arXiv:1305.3795. Bibcode:2013MNRAS.433.2097F. doi:10.1093/mnras/stt885.
  11. "BD+37 4734A". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2023-02-23.
  12. "BD+37 4734B". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2023-02-23.
  13. Aguilar, David A.; Pulliam, Christine (September 14, 2006). "Strange New Planet Baffles Astronomers" (Press release). Cambridge, Massachusetts: Harvard–Smithsonian Center for Astrophysics. Retrieved November 18, 2016.
  14. Turner, Jake D.; et al. (2016). "Ground-based near-UV observations of 15 transiting exoplanets: constraints on their atmospheres and no evidence for asymmetrical transits". Monthly Notices of the Royal Astronomical Society. 459 (1): 789–819. arXiv:1603.02587. Bibcode:2016MNRAS.459..789T. doi:10.1093/mnras/stw574.
External links