TOI-1136

TOI-1136 is a G-type main-sequence star 276 light-years (85 parsecs) away in the constellation Draco. It is slightly smaller than the Sun and similar in mass and temperature, but is much younger, with an age of about 700 million years. It hosts a system of at least six, and possibly seven, exoplanets.^[3]

TOI-1136

Observation data Epoch J2000      Equinox J2000
Constellation	Draco[1]
Right ascension	12h 48m 44.37261s[2]
Declination	+64° 51′ 19.1475″[2]
Apparent magnitude (V)	9.534[3]
Characteristics
Evolutionary stage	Main sequence
Spectral type	G5[4]
Apparent magnitude (B)	10.16±0.03[4]
Apparent magnitude (V)	9.534±0.003[3]
Apparent magnitude (G)	9.376±0.003[2]
Apparent magnitude (J)	8.363±0.020[4]
Apparent magnitude (H)	8.088±0.018[4]
Apparent magnitude (K)	8.034±0.021[4]
Astrometry
Radial velocity (Rv)	7.51±0.20[2] km/s
Proper motion (μ)	RA: 1.216 mas/yr[2] Dec.: -10.045 mas/yr[2]
Parallax (π)	11.8236±0.0108 mas[2]
Distance	275.9 ± 0.3 ly (84.58 ± 0.08 pc)
Details[3]
Mass	1.022±0.027 M☉
Radius	0.968±0.036 R☉
Surface gravity (log g)	4.47±0.04 cgs
Temperature	5770±50 K
Metallicity [Fe/H]	0.07±0.06 dex
Rotation	8.42±0.09 d[5]
Rotational velocity (v sin i)	6.7±0.6 km/s
Age	700±150 Myr
Other designations
BD+65 902, SAO 15908, PPM 18379, TOI-1136, TIC 142276270, TYC 4165-581-1, GSC 04165-00581, 2MASS J12484436+6451191[4]
Database references
SIMBAD	data
Exoplanet Archive	data

Artist's impression of known planets in the TOI-1136 system and their size comparison with Earth and Neptune

Planetary system

TOI-1136 was discovered to have six transiting planets in 2022 using the Transiting Exoplanet Survey Satellite (TESS), all orbiting closer to their star than Mercury is to the Sun.^[3] All of them are Neptune-sized or mini-Neptunes, and their masses have been measured using a combination of radial velocity and transit-timing variations, showing them to have low densities.^[5] The planets are in an orbital resonance, with period ratios near 3:2, 2:1, 3:2, 7:5, and 3:2.^[3]

A possible single transit of a seventh planet was also identified. This candidate planet would also be sub-Neptune-sized, but its orbit is poorly constrained. If this is confirmed, it would make TOI-1136 one of the largest known planetary systems.^[5]

The TOI-1136 planetary system^[3][5]

Companion (in order from star)	Mass	Semimajor axis (AU)	Orbital period (days)	Eccentricity	Inclination	Radius
b	3.50+0.8 −0.7 M🜨	0.05106±0.0009	4.1727±0.0003	0.027±0.009	86.44+0.27 −0.21°	1.90+0.21 −0.15 R🜨
c	6.32+1.1 −1.3 M🜨	0.0669±0.0005	6.2574±0.0002	0.11±0.01	89.42+0.39 −0.55°	2.879+0.060 −0.062 R🜨
d	8.35+1.8 −1.6 M🜨	0.1062±0.0008	12.5199±0.0004	0.042±0.004	89.41±0.28°	4.627+0.077 −0.072 R🜨
e	6.07+1.09 −1.01 M🜨	0.139±0.002	18.801±0.001	0.0425±0.004	89.31+0.26 −0.18°	2.639+0.072 −0.088 R🜨
f	9.7+3.9 −3.7 M🜨	0.174±0.002	26.321±0.001	0.001±0.001	89.38+0.22 −0.17°	3.88±0.11 R🜨
g	5.6+4.1 −3.2 M🜨	0.229±0.003	39.545±0.002	0.04±0.01	89.65+0.18 −0.13°	2.53+0.11 −0.12 R🜨
h (unconfirmed)	<18.8 M🜨	~0.36	~77	0.04+0.05 −0.03	89.68±0.02°	2.68+0.20 −0.18 R🜨

See also

• HD 110067
• Kepler-90
• Kepler-385
• TOI-178
• TRAPPIST-1