Registry · exoplanet

HAT-P-9 b

Exoplanet 75 papers

harvesting The full record is being pulled from the archives right now — measurement tables, the Gaia row, catalogue photometry. This page will fill itself in.

Right ascension: 07h 20m 40.44s
Declination: +37° 08′ 26.1″
Galactic l, b: 181.09, 21.44
Magnitude V: 12.34
Distance: 455.2 pc

Also known as

1 identifiers

HAT-P-9b

Planet

NASA Exoplanet Archive, composite parameters

Host star	HAT-P-9 · F
Discovery	Transit, 2008 · HATNet
Orbital period	3.92281 d
Semi-major axis	0.05287 au
Eccentricity	0.084
Radius	15.614 R⊕ · 1.393 R♃
Mass	238.05 M⊕ · 0.749 M♃
Density	0.342 g/cm³
Equilibrium temperature	1,540 K
System distance	455.2 pc

Published measurements

6 quantities measured more than once

One object can carry a dozen published estimates of the same quantity. The register keeps them side by side rather than picking a winner — the citation is part of the value.

Mass 5 values

Value	Unit	Uncertainty	Band / method	Source	Reference	Year
238.0547	M_earth	± 20.34	Transit	NASA Exoplanet Archive	Wang et al. 2019	2019
241.8686	M_earth	± 31.78	Transit	NASA Exoplanet Archive	Bonomo et al. 2017	2017
247.2717	M_earth	± 26.38	Transit	NASA Exoplanet Archive	Southworth 2012	2012
212.9461	M_earth	± 25.43	Transit	NASA Exoplanet Archive	Moutou et al. 2011	2011
247.9	M_earth	± 28.6	Transit	NASA Exoplanet Archive	Shporer et al. 2009	2009

Radius 6 values

Value	Unit	Uncertainty	Band / method	Source	Reference	Year
15.61414	R_earth	± 0.751	Transit	NASA Exoplanet Archive	Wang et al. 2019	2019
15.6926	R_earth	± 0.6725	Transit	NASA Exoplanet Archive	Bonomo et al. 2017	2017
15.46842	R_earth	± 1.121	Transit	NASA Exoplanet Archive	Southworth 2012	2012
15.6926	R_earth		Transit	NASA Exoplanet Archive	Moutou et al. 2011	2011
15.69	R_earth	± 0.67	Transit	NASA Exoplanet Archive	Shporer et al. 2009	2009
15.8493	R_earth	± 0.8735	Transit	NASA Exoplanet Archive	ExoFOP	2008

Orbital period 10 values

Value	Unit	Uncertainty	Band / method	Source	Reference	Year
3.922811	d	± 3.90e-07	Transit	NASA Exoplanet Archive	Kokori et al. 2023	2023
3.922811	d	± 8.60e-07	Transit	NASA Exoplanet Archive	Ivshina & Winn 2022	2022
3.922811	d	± 8.00e-07	Transit	NASA Exoplanet Archive	Kokori et al. 2022	2022
3.922811	d	± 9.00e-07	Transit	NASA Exoplanet Archive	Patel & Espinoza 2022	2022
3.922811	d	± 1.02e-06	Transit	NASA Exoplanet Archive	Wang et al. 2019	2019
3.922814	d	± 2.00e-06	Transit	NASA Exoplanet Archive	Bonomo et al. 2017	2017
3.922814	d	± 2.00e-06	Transit	NASA Exoplanet Archive	Southworth 2012	2012
3.92289	d		Transit	NASA Exoplanet Archive	Moutou et al. 2011	2011
3.92289	d	± 4.00e-05	Transit	NASA Exoplanet Archive	Shporer et al. 2009	2009
3.922804	d	± 4.30e-06	Transit	NASA Exoplanet Archive	ExoFOP	2008

Semi-major axis 4 values

Value	Unit	Uncertainty	Band / method	Source	Reference	Year
0.05287	au	± 0.00078	Transit	NASA Exoplanet Archive	Wang et al. 2019	2019
0.0529	au	± 0.0017	Transit	NASA Exoplanet Archive	Bonomo et al. 2017	2017
0.0529	au	± 0.0014	Transit	NASA Exoplanet Archive	Southworth 2012	2012
0.053	au	± 0.002	Transit	NASA Exoplanet Archive	Shporer et al. 2009	2009

Eccentricity 4 values

Value	Uncertainty	Band / method	Source	Reference	Year
0.08	± 0.05	Transit	NASA Exoplanet Archive	Kokori et al. 2023	2023
0.084	± 0.052	Transit	NASA Exoplanet Archive	Wang et al. 2019	2019
0.16		Transit	NASA Exoplanet Archive	Bonomo et al. 2017	2017
0		Transit	NASA Exoplanet Archive	Shporer et al. 2009	2009

Equilibrium temperature 4 values

Value	Unit	Uncertainty	Band / method	Source	Reference	Year
1,540	K	± 32	Transit	NASA Exoplanet Archive	Wang et al. 2019	2019
1,540	K	± 53	Transit	NASA Exoplanet Archive	Southworth 2012	2012
1,530	K	± 40	Transit	NASA Exoplanet Archive	Shporer et al. 2009	2009
1,369	K		Transit	NASA Exoplanet Archive	ExoFOP	2008

In the same field

within 9 arcmin · wider search

Object	Type	Separation	V
HAT-P-9	EmLine*	0.2529″	12.34
87GB 071706.7+371227	Blazar	171″	—
ZTF J072025.97+370816.0	RRLyrae	173.3″	17.98
GALEX J072025.5+370336	WhiteDwarf	340.3″	—

Provenance

where this card came from

Archive	Read at (UTC)	Record
Seeded from the bulk archive load; no per-object fetch yet.

Machine-readable: /api/v1/object/hat-p-9-b · Registry entry updated 2026-08-14.