ABSTRACT Planets with radii between that of the Earth and Neptune (hereafter referred to as ‘sub-Neptunes’) are found in close-in orbits around more than half of all Sun-like stars1,2.

However, their composition, formation and evolution remain poorly understood3. The study of multiplanetary systems offers an opportunity to investigate the outcomes of planet formation and

evolution while controlling for initial conditions and environment. Those in resonance (with their orbital periods related by a ratio of small integers) are particularly valuable because

they imply a system architecture practically unchanged since its birth. Here we present the observations of six transiting planets around the bright nearby star HD 110067. We find that the

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Contact customer support SIMILAR CONTENT BEING VIEWED BY OTHERS THE FORMATION OF THE TRAPPIST-1 SYSTEM IN TWO STEPS DURING THE RECESSION OF THE DISK INNER EDGE Article 20 August 2024

VERY-WIDE-ORBIT PLANETS FROM DYNAMICAL INSTABILITIES DURING THE STELLAR BIRTH CLUSTER PHASE Article 27 May 2025 AN UPPER LIMIT ON LATE ACCRETION AND WATER DELIVERY IN THE TRAPPIST-1

EXOPLANET SYSTEM Article 25 November 2021 DATA AVAILABILITY The TESS observations used in this study are publicly available at the Mikulski Archive for Space Telescopes

(https://archive.stsci.edu/missions-and-data/tess). The CHEOPS observations used in this study are available at the CHEOPS mission archive

(https://cheops-archive.astro.unige.ch/archive_browser/). The ground-based photometry and high-resolution imaging observations are uploaded to ExoFOP

(https://exofop.ipac.caltech.edu/tess/target.php?id=347332255) and are publicly available. CARMENES and HARPS-N reduced spectra, together with the derived CCF-based radial velocities and

spectral indicators, are available at Zenodo (https://doi.org/10.5281/zenodo.8211589). All reduced transit photometry and radial velocity measurements used in this work are also provided at

Zenodo (https://doi.org/10.5281/zenodo.8211589). CODE AVAILABILITY We used the following publicly available codes, resources and Python packages to reduce, analyse and interpret our

observations of HD 110067: numpy (ref. 155), matplotlib (ref. 156), astropy (ref. 157), lightkurve (ref. 44), PIPE (ref. 51,52), AstroImageJ (ref. 58), raccoon (ref. 73), serval (ref. 74),

ARES (refs. 79,80), MOOG (ref. 81), ZASPE (ref. 83), emcee (ref. 158), CLES (ref. 96), exoplanet (ref. 99), MonoTools (ref. 106), pymc3 (ref. 117), ArviZ (ref. 120), GLS (ref. 121), MCMCI

(ref. 132) and pyaneti (refs. 136,139). We can share the code used in the data reduction or data analysis on request. REFERENCES * Howard, A. W. et al. Planet occurrence within 0.25 AU of

solar-type stars from Kepler. _Astrophys. J. Suppl._ 201, 15 (2012). Article  ADS  Google Scholar  * Fressin, F. et al. The false positive rate of Kepler and the occurrence of planets.

_Astrophys. J._ 766, 81 (2013). Article  ADS  Google Scholar  * Bean, J. L., Raymond, S. N. & Owen, J. E. The nature and origins of sub-Neptune size planets. _J. Geophys. Res. Planets_

126, e06639 (2021). Article  Google Scholar  * Ricker, G. R. et al. Transiting Exoplanet Survey Satellite (TESS). _J. Astron. Telesc. Instrum. Syst._ 1, 014003 (2015). Article  ADS  Google

Scholar  * Jenkins, J. M. et al. in _Software and Cyberinfrastructure for Astronomy IV_ (eds Chiozzi, G. & Guzman, J. C.) 99133E (SPIE, 2016). * Benz, W. et al. The CHEOPS mission. _Exp.

Astron._ 51, 109–151 (2021). Article  ADS  Google Scholar  * Sinclair, A. T. The orbital resonance amongst the Galilean satellites of Jupiter. _Mon. Not. R. Astron. Soc._ 171, 59–72 (1975).

Article  ADS  MATH  Google Scholar  * Morbidelli, A. _Modern Celestial Mechanics: Aspects of Solar System Dynamics_ (Taylor & Francis, 2002). * Papaloizou, J. C. B. Three body

resonances in close orbiting planetary systems: tidal dissipation and orbital evolution. _Int. J. Astrobiol._ 14, 291–304 (2015). Article  ADS  Google Scholar  * Leleu, A. et al. Six

transiting planets and a chain of Laplace resonances in TOI-178. _Astron. Astrophys._ 649, A26 (2021). Article  CAS  Google Scholar  * Luger, R. et al. A seven-planet resonant chain in

TRAPPIST-1. _Nat. Astron._ 1, 0129 (2017). Article  ADS  Google Scholar  * Goździewski, K., Migaszewski, C., Panichi, F. & Szuszkiewicz, E. The Laplace resonance in the Kepler-60

planetary system. _Mon. Not. R. Astron. Soc._ 455, L104–L108 (2016). Article  ADS  Google Scholar  * Agol, E. et al. Refining the transit-timing and photometric analysis of TRAPPIST-1:

masses, radii, densities, dynamics, and ephemerides. _Planet Sci. J._ 2, 1 (2021). Article  Google Scholar  * Dai, F. et al. TOI-1136 is a young, coplanar, aligned planetary system in a

pristine resonant chain. _Astron. J._ 165, 33 (2023). Article  ADS  Google Scholar  * Quirrenbach, A. et al. in _Ground-based and Airborne Instrumentation for Astronomy VIII_, (eds Evans, C.

J., Bryant, J. J. & Motohara, K.) 114473C (SPIE, 2020). * Cosentino, R. et al. in _Ground-based and Airborne Instrumentation for Astronomy IV_ (eds McLean, I. S., Ramsay, S. K. &

Takami, H.) 84461V (SPIE, 2012). * Holman, M. J. & Murray, N. W. The use of transit timing to detect terrestrial-mass extrasolar planets. _Science_ 307, 1288–1291 (2005). Article  ADS 

CAS  PubMed  Google Scholar  * Fulton, B. J. et al. The California-Kepler survey. III. A gap in the radius distribution of small planets. _Astron. J._ 154, 109 (2017). Article  ADS  Google

Scholar  * Van Eylen, V. et al. An asteroseismic view of the radius valley: stripped cores, not born rocky. _Mon. Not. R. Astron. Soc._ 479, 4786–4795 (2018). Article  ADS  Google Scholar  *

Kasting, J. F., Whitmire, D. P. & Reynolds, R. T. Habitable zones around main sequence stars. _Icarus_ 101, 108–128 (1993). Article  ADS  CAS  PubMed  Google Scholar  * Kopparapu, R. K.

et al. Habitable zones around main-sequence stars: dependence on planetary mass. _Astrophys. J. Lett._ 787, L29 (2014). Article  ADS  Google Scholar  * Izidoro, A. et al. Formation of

planetary systems by pebble accretion and migration. Hot super-Earth systems from breaking compact resonant chains. _Astron. Astrophys._ 650, A152 (2021). Article  Google Scholar  *

Fabrycky, D. C. et al. Architecture of Kepler’s multi-transiting systems. II. New investigations with twice as many candidates. _Astrophys. J._ 790, 146 (2014). Article  ADS  Google Scholar

  * Zeng, L. et al. Growth model interpretation of planet size distribution. _Proc. Natl Acad. Sci. USA_ 116, 9723–9728 (2019). Article  ADS  CAS  PubMed  PubMed Central  Google Scholar  *

Kempton, E. M. R. et al. A framework for prioritizing the TESS planetary candidates most amenable to atmospheric characterization. _Proc. Acad. Sci. Pac._ 130, 114401 (2018). ADS  Google

Scholar  * Otegi, J. F., Bouchy, F. & Helled, R. Revisited mass-radius relations for exoplanets below 120 _M_⊕. _Astron. Astrophys._ 634, A43 (2020). Article  ADS  CAS  Google Scholar  *

Stassun, K. G. et al. The TESS input catalog and candidate target list. _Astron. J._ 156, 102 (2018). Article  ADS  Google Scholar  * Stumpe, M. C. et al. Kepler Presearch Data Conditioning

I—architecture and algorithms for error correction in Kepler light curves. _Proc. Acad. Sci. Pac._ 124, 985 (2012). ADS  Google Scholar  * Stumpe, M. C. et al. Multiscale systematic error

correction via wavelet-based bandsplitting in Kepler data. _Proc. Acad. Sci. Pac._ 126, 100 (2014). ADS  Google Scholar  * Smith, J. C. et al. Kepler Presearch Data Conditioning II - a

Bayesian approach to systematic error correction. _Proc. Acad. Sci. Pac._ 124, 1000 (2012). ADS  Google Scholar  * Jenkins, J. M. The impact of solar-like variability on the detectability of

transiting terrestrial planets. _Astrophys. J._ 575, 493–505 (2002). Article  ADS  Google Scholar  * Jenkins, J. M. et al. in _Software and Cyberinfrastructure for Astronomy_ (eds

Radziwill, N. M. & Bridger, A.) 77400D (SPIE, 2010). * Jenkins, J. M. et al. Kepler Data Processing Handbook: Transiting Planet Search. Kepler Science Document KSCI-19081-003 (2020). *

Twicken, J. D. et al. Kepler data validation I—architecture, diagnostic tests, and data products for vetting transiting planet candidates. _Proc. Acad. Sci. Pac._ 130, 064502 (2018). ADS 

Google Scholar  * Li, J. et al. Kepler data validation II-transit model fitting and multiple-planet search. _Proc. Acad. Sci. Pac._ 131, 024506 (2019). ADS  Google Scholar  * Guerrero, N. M.

et al. The TESS Objects of Interest Catalog from the TESS Prime Mission. _Astrophys. J. Suppl. Ser._ 254, 39 (2021). Article  ADS  Google Scholar  * Fausnaugh, M. M., Burke, C. J., Ricker,

G. R. & Vanderspek, R. Calibrated full-frame images for the TESS Quick Look Pipeline. _Res. Notes AAS_ 4, 251 (2020). Article  ADS  Google Scholar  * Hedges, C. et al. TOI-2076 and

TOI-1807: two young, comoving planetary systems within 50 pc identified by TESS that are ideal candidates for further follow up. _Astron. J._ 162, 54 (2021). Article  ADS  CAS  Google

Scholar  * Osborn, H. et al. Two warm Neptunes transiting HIP 9618 revealed by TESS & Cheops. _Mon. Not. R. Astron. Soc._ 523, 3069–3089 (2023). Article  ADS  Google Scholar  *

Vanderburg, A. et al. TESS spots a compact system of super-Earths around the naked-eye star HR 858. _Astrophys. J. Lett._ 881, L19 (2019). Article  ADS  CAS  Google Scholar  * Deming, D. et

al. Spitzer secondary eclipses of the dense, modestly-irradiated, giant exoplanet HAT-P-20b using pixel-level decorrelation. _Astrophys. J._ 805, 132 (2015). Article  ADS  Google Scholar  *

Luger, R. et al. EVEREST: pixel level decorrelation of K2 light curves. _Astron. J._ 152, 100 (2016). Article  ADS  Google Scholar  * Luger, R. et al. starry: analytic occultation light

curves. _Astron. J._ 157, 64 (2019). Article  ADS  Google Scholar  * Lightkurve Collaboration et al. Lightkurve: Kepler and TESS time series analysis in Python. Astrophysics Source Code

Library, record ascl:1812.013 (2018). * Gilliland, R. L. et al. Kepler mission stellar and instrument noise properties. _Astrophys. J. Suppl. Ser._ 197, 6 (2011). Article  ADS  Google

Scholar  * Van Cleve, J. E. et al. That’s how we roll: the NASA K2 mission science products and their performance metrics. _Proc. Acad. Sci. Pac._ 128, 075002 (2016). ADS  Google Scholar  *

Schanche, N. et al. TOI-2257 b: a highly eccentric long-period sub-Neptune transiting a nearby M dwarf. _Astron. Astrophys._ 657, A45 (2022). Article  Google Scholar  * Ulmer-Moll, S. et al.

Two long-period transiting exoplanets on eccentric orbits: NGTS-20 b (TOI-5152 b) and TOI-5153 b. _Astron. Astrophys._ 666, A46 (2022). Article  CAS  Google Scholar  * Osborn, A. et al.

TOI-431/HIP 26013: a super-Earth and a sub-Neptune transiting a bright, early K dwarf, with a third RV planet. _Mon. Not. R. Astron. Soc._ 507, 2782–2803 (2021). Article  ADS  Google Scholar

  * Tuson, A. et al. TESS and CHEOPS discover two warm sub-Neptunes transiting the bright K-dwarf HD 15906. _Mon. Not. R. Astron. Soc._ 523, 3090–3118 (2023). Article  ADS  Google Scholar  *

Szabó, G. M. et al. The changing face of AU Mic b: stellar spots, spin-orbit commensurability, and transit timing variations as seen by CHEOPS and TESS. _Astron. Astrophys._ 654, A159

(2021). Article  Google Scholar  * Morris, B. M. et al. CHEOPS precision phase curve of the Super-Earth 55 Cancri e. _Astron. Astrophys._ 653, A173 (2021). Article  Google Scholar  * Hoyer,

S. et al. Expected performances of the Characterising Exoplanet Satellite (CHEOPS). III. Data reduction pipeline: architecture and simulated performances. _Astron. Astrophys._ 635, A24

(2020). Article  Google Scholar  * Narita, N. et al. MuSCAT2: four-color simultaneous camera for the 1.52-m Telescopio Carlos Sánchez. _J. Astron. Telesc. Instrum. Syst._ 5, 015001 (2019).

ADS  Google Scholar  * Parviainen, H. et al. MuSCAT2 multicolour validation of TESS candidates: an ultra-short-period substellar object around an M dwarf. _Astron. Astrophys._ 633, A28

(2020). Article  CAS  Google Scholar  * Brown, T. M. et al. Las Cumbres Observatory global telescope network. _Proc. Acad. Sci. Pac._ 125, 1031 (2013). ADS  Google Scholar  * McCully, C. et

al. in _Software and Cyberinfrastructure for Astronomy V_ (eds Guzman, J. C. & Ibsen, J.) 107070K (2018). * Collins, K. A., Kielkopf, J. F., Stassun, K. G. & Hessman, F. V.

AstroImageJ: image processing and photometric extraction for ultra-precise astronomical light curves. _Astron. J._ 153, 77 (2017). Article  ADS  Google Scholar  * Wheatley, P. J. et al. The

Next Generation Transit Survey (NGTS). _Mon. Not. R. Astron. Soc._ 475, 4476–4493 (2018). Article  ADS  CAS  Google Scholar  * Garcia-Mejia, J. et al. in _Ground-based and Airborne

Telescopes VIII_ (eds Marshall, H. K., Spyromilio, J. & Usuda, T.) 114457R (SPIE, 2020). * Demory, B. O. et al. A super-Earth and a sub-Neptune orbiting the bright, quiet M3 dwarf

TOI-1266. _Astron. Astrophys._ 642, A49 (2020). Article  CAS  Google Scholar  * Narita, N. et al. in _Ground-based and Airborne Instrumentation for Astronomy VIII_ (eds Evans, C. J., Bryant,

J. J. & Motohara, K.) 114475K (SPIE, 2020). * Fukui, A. et al. Measurements of transit timing variations for WASP-5b. _Pub. Astron. Soc. Jpn._ 63, 287–300 (2011). Article  ADS  Google

Scholar  * Ciardi, D. R., Beichman, C. A., Horch, E. P. & Howell, S. B. Understanding the effects of stellar multiplicity on the derived planet radii from transit surveys: implications

for Kepler, K2, and TESS. _Astrophys. J._ 805, 16 (2015). Article  ADS  Google Scholar  * Hayward, T. L. et al. PHARO: a near-infrared camera for the Palomar Adaptive Optics System. _Proc.

Acad. Sci. Pac._ 113, 105–118 (2001). ADS  Google Scholar  * Dekany, R. et al. PALM-3000: exoplanet adaptive optics for the 5 m Hale telescope. _Astrophys. J._ 776, 130 (2013). Article  ADS

  Google Scholar  * Furlan, E. et al. The Kepler follow-up observation program. I. A catalog of companions to Kepler stars from high-resolution imaging. _Astron. J._ 153, 71 (2017). Article

  ADS  Google Scholar  * Scott, N. J. et al. Twin high-resolution, high-speed imagers for the Gemini telescopes: instrument description and science verification results. _Front. Astron.

Space Sci._ 8, 138 (2021). Article  ADS  Google Scholar  * Howell, S. B., Everett, M. E., Sherry, W., Horch, E. & Ciardi, D. R. Speckle camera observations for the NASA Kepler Mission

Follow-up Program. _Astron. J._ 142, 19 (2011). Article  ADS  Google Scholar  * Mugrauer, M. & Michel, K.-U. Gaia search for stellar companions of TESS Objects of Interest. _Astron.

Nachr._ 341, 996–1030 (2020). Article  ADS  Google Scholar  * Mugrauer, M. & Michel, K.-U. Gaia search for stellar companions of TESS Objects of Interest II. _Astron. Nachr._ 342,

840–864 (2021). Article  ADS  Google Scholar  * Ziegler, C. et al. SOAR TESS survey. I. Sculpting of TESS planetary systems by stellar companions. _Astron. J._ 159, 19 (2020). Article  ADS 

Google Scholar  * Lafarga, M. et al. The CARMENES search for exoplanets around M dwarfs. Radial velocities and activity indicators from cross-correlation functions with weighted binary

masks. _Astron. Astrophys._ 636, A36 (2020). Article  Google Scholar  * Zechmeister, M. et al. Spectrum radial velocity analyser (SERVAL). High-precision radial velocities and two

alternative spectral indicators. _Astron. Astrophys._ 609, A12 (2018). Article  Google Scholar  * Cosentino, R. et al. in _Ground-based and Airborne Instrumentation for Astronomy V_ (eds

Ramsay, S. K., McLean, I. S. & Takami, H.) 91478C (SPIE, 2014). * Santos, N. C. et al. SWEET-Cat: a catalogue of parameters for Stars With ExoplanETs. I. New atmospheric parameters and

masses for 48 stars with planets. _Astron. Astrophys._ 556, A150 (2013). Article  Google Scholar  * Sousa, S. G. _ARES + MOOG: A Practical Overview of an Equivalent Width (EW) Method to

Derive Stellar Parameters_ 297–310 (Springer, 2014). * Sousa, S. G. et al. SWEET-Cat 2.0: The Cat just got SWEETer. Higher quality spectra and precise parallaxes from Gaia eDR3. _Astron.

Astrophys._ 656, A53 (2021). Article  Google Scholar  * Sousa, S. G., Santos, N. C., Israelian, G., Mayor, M. & Monteiro, M. J. P. F. G. A new code for automatic determination of

equivalent widths: Automatic Routine for line Equivalent widths in stellar Spectra (ARES). _Astron. Astrophys._ 469, 783–791 (2007). Article  ADS  Google Scholar  * Sousa, S. G., Santos, N.

C., Adibekyan, V., Delgado-Mena, E. & Israelian, G. ARES v2: new features and improved performance. _Astron. Astrophys._ 577, A67 (2015). Article  ADS  Google Scholar  * Sneden, C. A.

_Carbon and Nitrogen Abundances in Metal-Poor Stars_. PhD thesis, Univ. Texas at Austin (1973). * Kurucz, R. L. SYNTHE spectrum synthesis programs and line data. Astrophysics Source Code

Library (1993). * Brahm, R., Jordán, A., Hartman, J. & Bakos, G. ZASPE: a code to measure stellar atmospheric parameters and their covariance from spectra. _Mon. Not. R. Astron. Soc._

467, 971–984 (2017). ADS  CAS  Google Scholar  * Adibekyan, V. Zh. et al. Chemical abundances of 1111 FGK stars from the HARPS GTO planet search program. Galactic stellar populations and

planets. _Astron. Astrophys._ 545, A32 (2012). Article  Google Scholar  * Adibekyan, V. et al. Identifying the best iron-peak and _α_-capture elements for chemical tagging: the impact of the

number of lines on measured scatter. _Astron. Astrophys._ 583, A94 (2015). Article  Google Scholar  * Castelli, F. & Kurucz, R. L. in _Modelling of Stellar Atmospheres, Proc. 210th

Symposium of the International Astronomical Union_ (eds Piskunov, N., Weiss, W. W. & Gray, D. F.) A20 (Astronomical Society of the Pacific, 2003). * Allard, F. in _Exploring the

Formation and Evolution of Planetary Systems, Proc. IAU Symposium No. 299_ (eds Booth, M., Matthews, B. C. & Graham, J. R.) 271–272 (International Astronomical Union, 2014). * Blackwell,

D. E. & Shallis, M. J. Stellar angular diameters from infrared photometry. Application to Arcturus and other stars; with effective temperatures. _Mon. Not. R. Astron. Soc._ 180, 177–191

(1977). Article  ADS  Google Scholar  * Schanche, N. et al. WASP-186 and WASP-187: two hot Jupiters discovered by SuperWASP and SOPHIE with additional observations by TESS. _Mon. Not. R.

Astron. Soc._ 499, 428–440 (2020). Article  ADS  CAS  Google Scholar  * Wilson, T. G. et al. A pair of sub-Neptunes transiting the bright K-dwarf TOI-1064 characterized with CHEOPS. _Mon.

Not. R. Astron. Soc._ 511, 1043–1071 (2022). Article  ADS  CAS  Google Scholar  * Lindegren, L. et al. Gaia Early Data Release 3. Parallax bias versus magnitude, colour, and position.

_Astron. Astrophys._ 649, A4 (2021). Article  Google Scholar  * Bonfanti, A. et al. CHEOPS observations of the HD 108236 planetary system: a fifth planet, improved ephemerides, and planetary

radii. _Astron. Astrophys._ 646, A157 (2021). Article  CAS  Google Scholar  * Bonfanti, A., Ortolani, S., Piotto, G. & Nascimbeni, V. Revising the ages of planet-hosting stars. _Astron.

Astrophys._ 575, A18 (2015). Article  ADS  Google Scholar  * Bonfanti, A., Ortolani, S. & Nascimbeni, V. Age consistency between exoplanet hosts and field stars. _Astron. Astrophys._

585, A5 (2016). Article  ADS  Google Scholar  * Marigo, P. et al. A new generation of PARSEC-COLIBRI stellar isochrones including the TP-AGB phase. _Astrophys. J._ 835, 77 (2017). Article 

ADS  Google Scholar  * Scuflaire, R. et al. CLÉS, Code Liégeois d’Évolution Stellaire. _Astrophys. Space Sci._ 316, 83–91 (2008). Article  ADS  Google Scholar  * Salmon, S. J. A. J., Van

Grootel, V., Buldgen, G., Dupret, M. A. & Eggenberger, P. Reinvestigating _α_ Centauri AB in light of asteroseismic forward and inverse methods. _Astron. Astrophys._ 646, A7 (2021).

Article  Google Scholar  * Reddy, B. E., Lambert, D. L. & Allende Prieto, C. Elemental abundance survey of the Galactic thick disc. _Mon. Not. R. Astron. Soc._ 367, 1329–1366 (2006).

Article  ADS  CAS  Google Scholar  * Foreman-Mackey, D. et al. dfm/exoplanet: exoplanet v0.2.1. Zenodo https://zenodo.org/record/3462740 (2019). * Delrez, L. et al. Transit detection of the

long-period volatile-rich super-Earth _ν_2 Lupi d with CHEOPS. _Nat. Astron._ 5, 775–787 (2021). Article  ADS  Google Scholar  * Claret, A. A new method to compute limb-darkening

coefficients for stellar atmosphere models with spherical symmetry: the space missions TESS, Kepler, CoRoT, and MOST. _Astron. Astrophys._ 618, A20 (2018). Article  ADS  Google Scholar  *

Claret, A. Limb and gravity-darkening coefficients for the Space Mission CHEOPS. _Res. Notes AAS_ 5, 13 (2021). Article  ADS  Google Scholar  * Van Eylen, V. & Albrecht, S. Eccentricity

from transit photometry: small planets in Kepler multi-planet systems have low eccentricities. _Astrophys. J._ 808, 126 (2015). Article  ADS  Google Scholar  * Xie, J.-W. et al. Exoplanet

orbital eccentricities derived from LAMOST–Kepler analysis. _Proc. Natl Acad. Sci. USA_ 113, 11431–11435 (2016). Article  ADS  CAS  PubMed  PubMed Central  Google Scholar  * Hadden, S. &

Lithwick, Y. Kepler planet masses and eccentricities from TTV analysis. _Astron. J._ 154, 5 (2017). Article  ADS  Google Scholar  * Osborn, H. P. MonoTools: planets of uncertain periods

detector and modeler. Astrophysics Source Code Library, record ascl:2204.020 (2022). * Kipping, D. The orbital period prior for single transits. _Res. Notes AAS_ 2, 223 (2018). Article  ADS

  Google Scholar  * Van Eylen, V. et al. The orbital eccentricity of small planet systems. _Astron. J._ 157, 61 (2019). Article  ADS  Google Scholar  * Osborn, H. P. et al. Uncovering the

true periods of the young sub-Neptunes orbiting TOI-2076. _Astron. Astrophys._ 664, A156 (2022). Article  Google Scholar  * Mills, S. M. et al. A resonant chain of four transiting,

sub-Neptune planets. _Nature_ 533, 509–512 (2016). Article  ADS  CAS  PubMed  Google Scholar  * Siegel, J. C. & Fabrycky, D. Resonant chains of exoplanets: libration centers for

three-body angles. _Astron. J._ 161, 290 (2021). Article  ADS  Google Scholar  * Lopez, T. A. et al. Exoplanet characterisation in the longest known resonant chain: the K2-138 system seen by

HARPS. _Astron. Astrophys._ 631, A90 (2019). Article  CAS  Google Scholar  * Rein, H. & Liu, S. F. REBOUND: an open-source multi-purpose N-body code for collisional dynamics. _Astron.

Astrophys._ 537, A128 (2012). Article  ADS  Google Scholar  * Delisle, J.-B. samsam: Scaled Adaptive Metropolis SAMpler. Astrophysics Source Code Library, record ascl:2207.011 (2022). *

Leleu, A. et al. Removing biases on the density of sub-Neptunes characterised via transit timing variations. Update on the mass-radius relationship of 34 Kepler planets. _Astron. Astrophys._

669, A117 (2023). Article  CAS  Google Scholar  * Parviainen, H. & Aigrain, S. ldtk: Limb Darkening Toolkit. _Mon. Not. R. Astron. Soc._ 453, 3821–3826 (2015). Article  ADS  Google

Scholar  * Salvatier, J., Wiecki, T. V. & Fonnesbeck, C. Probabilistic programming in Python using PyMC3. _PeerJ Comput. Sci._ 2, e55 (2016). Article  Google Scholar  * Watanabe, S.

& Opper, M. Asymptotic equivalence of Bayes cross validation and widely applicable information criterion in singular learning theory. _J. Mach. Learn. Res._ 11, 3571–3594 (2010).

MathSciNet  MATH  Google Scholar  * Vehtari, A., Gelman, A. & Gabry, J. Practical Bayesian model evaluation using leave-one-out cross-validation and WAIC. _Stat. Comput._ 27, 1413–1432

(2017). Article  MathSciNet  MATH  Google Scholar  * ArviZ Developers. ArviZ: exploratory analysis of Bayesian models. Astrophysics Source Code Library, record ascl:2004.012 (2020). *

Zechmeister, M. & Kürster, M. The generalised Lomb-Scargle periodogram. A new formalism for the floating-mean and Keplerian periodograms. _Astron. Astrophys._ 496, 577–584 (2009).

Article  ADS  Google Scholar  * Saar, S. H. & Donahue, R. A. Activity-related radial velocity variation in cool stars. _Astrophys. J._ 485, 319–327 (1997). Article  ADS  Google Scholar 

* Hatzes, A. P. Starspots and exoplanets. _Astron. Nachr._ 323, 392–394 (2002). Article  ADS  CAS  Google Scholar  * Meunier, N., Desort, M. & Lagrange, A. M. Using the Sun to estimate

Earth-like planets detection capabilities. II. Impact of plages. _Astron. Astrophys._ 512, A39 (2010). Article  ADS  Google Scholar  * Dumusque, X., Boisse, I. & Santos, N. C. SOAP 2.0:

a tool to estimate the photometric and radial velocity variations induced by stellar spots and plages. _Astrophys. J._ 796, 132 (2014). Article  ADS  Google Scholar  * Queloz, D. et al. No

planet for HD 166435. _Astron. Astrophys._ 379, 279–287 (2001). Article  ADS  CAS  Google Scholar  * Boisse, I. et al. Stellar activity of planetary host star HD 189 733. _Astron.

Astrophys._ 495, 959–966 (2009). Article  ADS  CAS  Google Scholar  * Dumusque, X. Radial velocity fitting challenge. I. Simulating the data set including realistic stellar radial-velocity

signals. _Astron. Astrophys._ 593, A5 (2016). Article  ADS  Google Scholar  * Simola, U., Dumusque, X. & Cisewski-Kehe, J. Measuring precise radial velocities and cross-correlation

function line-profile variations using a Skew Normal density. _Astron. Astrophys._ 622, A131 (2019). Article  ADS  CAS  Google Scholar  * Simola, U. et al. Accounting for stellar activity

signals in radial-velocity data by using change point detection techniques. _Astron. Astrophys._ 664, A127 (2022). Article  Google Scholar  * Bonfanti, A. et al. TOI-1055 b: Neptunian planet

characterised with HARPS, TESS, and CHEOPS. _Astron. Astrophys._ 671, L8 (2023). * Bonfanti, A. & Gillon, M. MCMCI: a code to fully characterise an exoplanetary system. _Astron.

Astrophys._ 635, A6 (2020). Article  ADS  CAS  Google Scholar  * Schwarz, G. Estimating the dimension of a model. _Ann. Stat._ 6, 461–464 (1978). Article  MathSciNet  MATH  Google Scholar  *

Gelman, A. & Rubin, D. B. Inference from iterative simulation using multiple sequences. _Stat. Sci._ 7, 457–472 (1992). Article  MATH  Google Scholar  * Rajpaul, V., Aigrain, S.,

Osborne, M. A., Reece, S. & Roberts, S. A Gaussian process framework for modelling stellar activity signals in radial velocity data. _Mon. Not. R. Astron. Soc._ 452, 2269–2291 (2015).

Article  ADS  CAS  Google Scholar  * Barragán, O., Aigrain, S., Rajpaul, V. M. & Zicher, N. PYANETI - II. A multidimensional Gaussian process approach to analysing spectroscopic

time-series. _Mon. Not. R. Astron. Soc._ 509, 866–883 (2022). Article  ADS  Google Scholar  * Barragán, O. et al. The young HD 73583 (TOI-560) planetary system: two 10-M⊕ mini-Neptunes

transiting a 500-Myr-old, bright, and active K dwarf. _Mon. Not. R. Astron. Soc._ 514, 1606–1627 (2022). Article  ADS  Google Scholar  * Zicher, N. et al. One year of AU Mic with HARPS – I.

Measuring the masses of the two transiting planets. _Mon. Not. R. Astron. Soc._ 512, 3060–3078 (2022). Article  ADS  CAS  Google Scholar  * Barragán, O., Gandolfi, D. & Antoniciello, G.

PYANETI: a fast and powerful software suite for multiplanet radial velocity and transit fitting. _Mon. Not. R. Astron. Soc._ 482, 1017–1030 (2019). Article  ADS  Google Scholar  * Cale, B.

L. et al. Diving beneath the sea of stellar activity: chromatic radial velocities of the young AU Mic planetary system. _Astron. J._ 162, 295 (2021). Article  ADS  CAS  Google Scholar  *

Blunt, S. et al. Overfitting affects the reliability of radial velocity mass estimates of the V1298 Tau planets. _Astron. J._ 166, 62 (2023). * Dorn, C. et al. Can we constrain the interior

structure of rocky exoplanets from mass and radius measurements? _Astron. Astrophys._ 577, A83 (2015). Article  Google Scholar  * Dorn, C. et al. A generalized Bayesian inference method for

constraining the interiors of super Earths and sub-Neptunes. _Astron. Astrophys._ 597, A37 (2017). Article  Google Scholar  * Haldemann, J., Alibert, Y., Mordasini, C. & Benz, W. AQUA: a

collection of H2O equations of state for planetary models. _Astron. Astrophys._ 643, A105 (2020). Article  ADS  CAS  Google Scholar  * Hakim, K. et al. A new ab initio equation of state of

hcp-Fe and its implication on the interior structure and mass-radius relations of rocky super-Earths. _Icarus_ 313, 61–78 (2018). Article  ADS  CAS  Google Scholar  * Sotin, C., Grasset, O.

& Mocquet, A. Mass radius curve for extrasolar Earth-like planets and ocean planets. _Icarus_ 191, 337–351 (2007). Article  ADS  CAS  Google Scholar  * Lopez, E. D. & Fortney, J. J.

Understanding the mass–radius relation for sub-Neptunes: radius as a proxy for composition. _Astrophys. J._ 792, 1 (2014). Article  ADS  Google Scholar  * Thiabaud, A. et al. From stellar

nebula to planets: the refractory components. _Astron. Astrophys._ 562, A27 (2014). Article  Google Scholar  * Marboeuf, U., Thiabaud, A., Alibert, Y., Cabral, N. & Benz, W. From

planetesimals to planets: volatile molecules. _Astron. Astrophys._ 570, A36 (2014). Article  ADS  Google Scholar  * Venturini, J., Guilera, O. M., Haldemann, J., Ronco, M. P. &

Mordasini, C. The nature of the radius valley. Hints from formation and evolution models. _Astron. Astrophys._ 643, L1 (2020). Article  ADS  Google Scholar  * Emsenhuber, A. et al. The New

Generation Planetary Population Synthesis (NGPPS). II. Planetary population of solar-like stars and overview of statistical results. _Astron. Astrophys._ 656, A70 (2021). Article  CAS 

Google Scholar  * Izidoro, A. et al. The exoplanet radius valley from gas-driven planet migration and breaking of resonant chains. _Astrophys. J._ 939, L19 (2022). Article  ADS  Google

Scholar  * Hu, R. et al. Unveiling shrouded oceans on temperate sub-Neptunes via transit signatures of solubility equilibria versus gas thermochemistry. _Astrophys. J._ 921, L8 (2021).

Article  ADS  CAS  Google Scholar  * Tsai, S.-M. et al. Inferring shallow surfaces on sub-Neptune exoplanets with JWST. _Astrophys. J._ 922, L27 (2021). Article  ADS  CAS  Google Scholar  *

Harris, C. R. et al. Array programming with NumPy. _Nature_ 585, 357–362 (2020). Article  ADS  CAS  PubMed  PubMed Central  Google Scholar  * Hunter, J. D. Matplotlib: a 2D graphics

environment. _Comput. Sci. Eng._ 9, 90–95 (2007). Article  Google Scholar  * The Astropy Collaboration et al. The Astropy Project: sustaining and growing a community-oriented open-source

project and the latest major release (v5.0) of the core package. _Astrophys. J._ 935, 167 (2022). Article  ADS  Google Scholar  * Foreman-Mackey, D., Hogg, D. W., Lang, D. & Goodman, J.

emcee: the MCMC hammer. _Proc. Acad. Sci. Pac._ 125, 306 (2013). ADS  Google Scholar  * MacDonald, M. G., Shakespeare, C. J. & Ragozzine, D. A five-planet resonant chain: reevaluation of

the Kepler-80 system. _Astron. J._ 162, 114 (2021). Article  ADS  Google Scholar  * Cannon, A. J. & Pickering, E. C. The Henry Draper catalogue 0h, 1h, 2h, and 3h. _Ann. Harvard College

Observatory_ 91, 1–290 (1918). ADS  Google Scholar  * Gaia Collaboration et al. Gaia Early Data Release 3. Summary of the contents and survey properties. _Astron. Astrophys._ 649, A1

(2021). Article  Google Scholar  * Yoss, K. M. & Griffin, R. F. Radial velocities and DDO, BV photometry of Henry Draper G5-M stars near the North Galactic Pole. _J. Astrophys. Astron._

18, 161–227 (1997). Article  ADS  Google Scholar  * Skrutskie, M. F. et al. The Two Micron All Sky Survey (2MASS). _Astron. J._ 131, 1163–1183 (2006). Article  ADS  Google Scholar  *

Delisle, J. B. Analytical model of multi-planetary resonant chains and constraints on migration scenarios. _Astron. Astrophys._ 605, A96 (2017). Article  ADS  Google Scholar  Download

references ACKNOWLEDGEMENTS We acknowledge the use of public TESS data from pipelines at the TESS Science Office and at the TESS Science Processing Operations Center (SPOC). Resources

supporting this work were provided by the NASA High-End Computing (HEC) Program through the NASA Advanced Supercomputing (NAS) Division at Ames Research Center for the production of the SPOC

data products. The CHaracterising ExOPlanets Satellite (CHEOPS) is a European Space Agency (ESA) mission in partnership with Switzerland with important contributions to the payload and the

ground segment from Austria, Belgium, France, Germany, Hungary, Italy, Portugal, Spain, Sweden and the United Kingdom. The CHEOPS Consortium would like to gratefully acknowledge the support

received by all the agencies, offices, universities and industries involved. Their flexibility and willingness to explore new approaches were essential to the success of this mission.

CARMENES acknowledges financial support from the Agencia Estatal de Investigación of the Ministerio de Ciencia e Innovación MCIN/AEI/10.13039/501100011033 and the European Regional

Development Fund (ERDF) ‘A way of making Europe’ through projects PID2019-107061GB-C61, PID2019-107061GB-C66, PID2021-125627OB-C31 and PID2021-125627OB-C32, from the Centre of Excellence

‘Severo Ochoa’ award to the Instituto de Astrofísica de Canarias (IAC; CEX2019-000920-S), from the Centre of Excellence ‘María de Maeztu’ award to the Institut de Ciències de l’Espai

(CEX2020-001058-M) and from the Generalitat de Catalunya/CERCA programme. Based on observations made with the Italian Telescopio Nazionale Galileo (TNG) operated on the island of La Palma by

the Fundación Galileo Galilei of the Istituto Nazionale di Astrofisica (INAF) at the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofisica de Canarias. This

article is based on observations made with the MuSCAT2 instrument, developed by the Astrobiology Center (ABC), at Telescopio Carlos Sánchez operated on the island of Tenerife by the IAC in

the Spanish Observatorio del Teide. This paper is based on observations made with the MuSCAT3 instrument, developed by ABC and under financial supports by JSPS KAKENHI (JP18H05439) and JST

PRESTO (JPMJPR1775), at Faulkes Telescope North on Maui, Hawaii, operated by the Las Cumbres Observatory. Tierras is supported by grants from the John Templeton Foundation and the Harvard

Origins of Life Initiative. The opinions expressed in this publication are those of the authors and do not necessarily reflect the views of the John Templeton Foundation. The Next Generation

Transit Survey (NGTS) facility is operated by the consortium institutes with support from the UK Science and Technology Facilities Council (STFC) under projects ST/M001962/1 and

ST/S002642/1. Some of the observations presented in this paper were carried out at the Observatorio Astronómico Nacional on the Sierra de San Pedro Mártir (OAN-SPM), Baja California, México.

This work makes use of observations from the Las Cumbres Observatory global telescope network. Some of the observations in this paper made use of the High-Resolution Imaging instrument

Alopeke and were obtained under Gemini LLP Proposal Number GN-S-2021A-LP-105. Alopeke was funded by the NASA Exoplanet Exploration Program and built at the NASA Ames Research Center by S. B.

Howell, N. Scott, E. P. Horch and E. Quigley. Alopeke was mounted on the Gemini North telescope of the international Gemini Observatory, a programme of NSF OIR Lab, which is managed by the

Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with the National Science Foundation. On behalf of the Gemini partnership: the National Science

Foundation (United States), National Research Council (Canada), Agencia Nacional de Investigación y Desarrollo (Chile), Ministerio de Ciencia, Tecnología e Innovación (Argentina), Ministério

da Ciência, Tecnologia, Inovações e Comunicações (Brazil) and Korea Astronomy and Space Science Institute (Republic of Korea). This work was supported by the KESPRINT collaboration, an

international consortium devoted to the characterization and research of exoplanets discovered with space-based missions. R.Lu. thanks D. Fabrycky for helpful discussions about the orbital

dynamics of the HD 110067 system. R.Lu. acknowledges funding from University of La Laguna through the Margarita Salas Fellowship from the Spanish Ministry of Universities ref.

UNI/551/2021-May 26 and under the EU Next Generation funds. This work has been carried out within the framework of the National Centre for Competence in Research (NCCR) PlanetS supported by

the Swiss National Science Foundation (SNSF) under grants 51NF40_182901 and 51NF40_205606. A.C.Ca. and T.G.Wi. acknowledge support from STFC consolidated grant numbers ST/R000824/1 and

ST/V000861/1 and UKSA grant number ST/R003203/1. O.Ba. acknowledges funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme

(grant agreement no. 865624). M.Le. acknowledges support of the SNSF under grant number PCEFP2_194576. P.F.L.Ma. acknowledges support from STFC research grant number ST/M001040/1. Y.Al.

acknowledges support from the SNSF under grant 200020_192038. D.Ga. gratefully acknowledges financial support from the CRT foundation under grant no. 2018.2323 ‘Gaseous or rocky? Unveiling

the nature of small worlds’. J.A.Eg. acknowledges support from the SNSF under grant 200020_192038. G.No. is grateful for the research funding from the Ministry of Education and Science

programme ‘The Excellence Initiative – Research University’ conducted at the Centre of Excellence in Astrophysics and Astrochemistry of the Nicolaus Copernicus University in Torun, Poland.

D.Ra. was supported by NASA under award number NNA16BD14C for NASA Academic Mission Services. M.La. acknowledges funding from a UKRI Future Leader Fellowship, grant number MR/S035214/1.

V.Ad. is supported by Fundação para a Ciência e a Tecnologia (FCT) through national funds by grants UIDB/04434/2020, UIDP/04434/2020 and 2022.06962.PTDC. P.J.Am. acknowledges financial

support from grants CEX2021-001131-S and PID2019-109522GB-C52, both funded by MCIN/AEI/ 10.13039/501100011033 and by the ERDF ‘A way of making Europe’. S.C.C.Ba. acknowledges support from

FCT through FCT contract no. IF/01312/2014/CP1215/CT0004. X.Bo., S.Ch., D.Ga., M.Fr. and J.La. acknowledge their role as ESA-appointed CHEOPS science team members. L.Bo., V.Na., I.Pa.,

G.Pi., R.Ra., G.Sc., and T.Zi. acknowledge support from CHEOPS ASI-INAF agreement no. 2019-29-HH.0. A.Br. was supported by the Swedish National Space Agency (SNSA). Contributions at the

Mullard Space Science Laboratory by E.M.Br. were supported by STFC through the consolidated grant ST/W001136/1. S.C.-G. acknowledges support from UNAM PAPIIT-IG101321. D.Ch. and J.G.-M.

thank the staff at the F. L. Whipple Observatory for their assistance in the refurbishment and maintenance of the 1.3-m telescope. W.D.Co. acknowledges support from NASA grant 80NSSC23K0429.

This is University of Texas Center for Planetary Systems Habitability Contribution 0063. K.A.Co. acknowledges support from the TESS mission through subaward s3449 from MIT. H.J.De.

acknowledges support from the Spanish Research Agency of the Ministry of Science and Innovation (AEI-MICINN) under grant PID2019-107061GB-C66, doi:10.13039/501100011033. This project was

supported by the CNES. The Belgian participation to CHEOPS has been supported by the Belgian Federal Science Policy Office (BELSPO) in the framework of the PRODEX Program and by the

University of Liège through an ARC grant for Concerted Research Actions financed by the Wallonia-Brussels Federation. L.De. is an F.R.S.-FNRS Postdoctoral Researcher. This work was supported

by FCT through national funds and by FEDER through COMPETE2020 – Programa Operacional Competitividade e Internacionalizacão by these grants: UID/FIS/04434/2019, UIDB/04434/2020,

UIDP/04434/2020, PTDC/FIS-AST/32113/2017 and POCI-01-0145-FEDER-032113, PTDC/FIS-AST/28953/2017 and POCI-01-0145-FEDER-028953, PTDC/FIS-AST/28987/2017 and POCI-01-0145-FEDER-028987.

O.D.S.De. is supported in the form of work contract (DL 57/2016/CP1364/CT0004) funded by national funds through FCT. B.-O.De. acknowledges support from the Swiss State Secretariat for

Education, Research and Innovation (SERI) under contract number MB22.00046. This project has received funding from the ERC under the European Union’s Horizon 2020 research and innovation

programme (project Four Aces grant agreement no. 724427). It has also been carried out in the frame of the NCCR PlanetS supported by the SNSF. D.Eh. acknowledges financial support from the

SNSF for project 200021_200726. E.E.-B. acknowledges financial support from the European Union and the State Agency of Investigation of the Spanish Ministry of Science and Innovation

(MICINN) under the grant PRE2020-093107 of the Pre-Doc Program for the Training of Doctors (FPI-SO) through FSE funds. M.Fr. gratefully acknowledges the support of the Swedish National Space

Agency (DNR 65/19, 174/18). J.G.-M. acknowledges support by the National Science Foundation through a Graduate Research Fellowship under grant no. DGE1745303 and by the Ford Foundation

through a Ford Foundation Predoctoral Fellowship, administered by the National Academies of Sciences, Engineering, and Medicine. The contributions at the University of Warwick by S.Gi. have

been supported by STFC through consolidated grants ST/L000733/1 and ST/P000495/1. M.Gi. is F.R.S.-FNRS Research Director. Y.G.M.Ch. acknowledges support from UNAM PAPIIT-IG101321. E.Go.

acknowledges support by the Thueringer Ministerium füër Wirtschaft, Wissenschaft und Digitale Gesellschaft. M.N.Gu. is the ESA CHEOPS Project Scientist and Mission Representative and, as

such, is also responsible for the Guest Observers (GO) Programme. M.N.Gu. does not relay proprietary information between the GO and Guaranteed Time Observation (GTO) Programmes, and does not

decide on the definition and target selection of the GTO Programme. A.P.Ha. acknowledges support by DFG grant HA 3279/12-1 within the DFG Schwerpunkt SPP 1992. Ch.He. acknowledges support

from the European Union H2020-MSCA-ITN-2019 under grant agreement no. 860470 (CHAMELEON). S.Ho. gratefully acknowledges CNES funding through the grant 837319. This work is partly supported

by JST CREST grant number JPMJCR1761. K.G.Is. is the ESA CHEOPS Project Scientist and is responsible for the ESA CHEOPS GO Programme. She does not participate in, or contribute to, the

definition of the Guaranteed Time Programme of the CHEOPS mission through which observations described in this paper have been taken nor to any aspect of target selection for the programme.

J.Ko. gratefully acknowledges the support of the SNSA (DNR 2020-00104) and of the Swedish Research Council (VR: Etableringsbidrag 2017-04945). K.W.F.La. was supported by Deutsche

Forschungsgemeinschaft grants RA714/14-1 within the DFG Schwerpunkt SPP 1992, Exploring the Diversity of Extrasolar Planets. This work was granted access to the HPC resources of MesoPSL

financed by the Region Ile de France and the project Equip@Meso (reference ANR-10-EQPX-29-01) of the programme Investissements d’Avenir supervised by the Agence Nationale pour la Recherche.

A.L.desE. acknowledges support from the CNES (Centre national d’études spatiales, France). This work is partly supported by Astrobiology Center SATELLITE Research project AB022006. This work

is partly supported by JSPS KAKENHI grant number JP18H05439 and JST CREST grant number JPMJCR1761. H.L.M.Os. acknowledges funding support by STFC through a PhD studentship. H.Pa.

acknowledges the support by the Spanish Ministry of Science and Innovation with the Ramon y Cajal fellowship number RYC2021-031798-I. This work was also partially supported by a grant from

the Simons Foundation (PI: Queloz, grant number 327127). S.N.Qu. acknowledges support from the TESS mission through subaward s3449 from MIT. S.N.Qu. acknowledges support from the TESS GI

Program under award 80NSSC21K1056 (G03268). L.Sa. acknowledges support from UNAM PAPIIT project IN110122. N.C.Sa. acknowledges funding by the European Union (ERC, FIERCE, 101052347). Views

and opinions expressed are, however, those of the author(s) only and do not necessarily reflect those of the European Union or the ERC. Neither the European Union nor the granting authority

can be held responsible for them. N.Sc. acknowledges support from the SNSF (PP00P2-163967 and PP00P2-190080) and NASA under award number 80GSFC21M0002. S.G.So. acknowledges support from FCT

through FCT contract no. CEECIND/00826/2018 and POPH/FSE (EC). Gy.M.Sz. acknowledges the support of the Hungarian National Research, Development and Innovation Office (NKFIH) grant K-125015,

a PRODEX Experiment Agreement no. 4000137122, the Lendület LP2018-7/2021 grant of the Hungarian Academy of Science and the support of the city of Szombathely. A.Tu. acknowledges funding

support from the STFC through a PhD studentship. V.V.Ey. acknowledges support by the STFC through the consolidated grant ST/W001136/1. V.V.Gr. is an F.R.S.-FNRS Research Associate. J.Ve.

acknowledges support from the SNSF under grant PZ00P2_208945. N.A.Wa. acknowledges UKSA grant ST/R004838/1. N.Wa. is partly supported by JSPS KAKENHI grant number JP21K20376. AUTHOR

INFORMATION Author notes * These authors contributed equally: H. P. Osborn, A. Leleu, E. Pallé AUTHORS AND AFFILIATIONS * Department of Astronomy and Astrophysics, University of Chicago,

Chicago, IL, USA R. Luque & J. L. Bean * Space Research and Planetary Sciences, Physics Institute, University of Bern, Bern, Switzerland H. P. Osborn, A. Leleu, C. Broeg, Y. Alibert, J.

A. Egger, T. Beck, W. Benz, B.-O. Demory, A. Fortier, C. Mordasini, A. E. Simon & N. Thomas * Department of Physics, Massachusetts Institute of Technology, Cambridge, MA, USA H. P.

Osborn, K. M. Hesse, G. R. Ricker, A. Rudat, S. Seager, A. Shporer & A. M. Vanderburg * Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology,

Cambridge, MA, USA H. P. Osborn, K. M. Hesse, G. R. Ricker, A. Rudat, S. Seager, A. Shporer & A. M. Vanderburg * Observatoire Astronomique de l’Université de Genève, Versoix, Switzerland

A. Leleu, M. Lendl, J.-B. Delisle, M. Beck, N. Billot, A. Deline, D. Ehrenreich, S. Salmon, D. Ségransan, S. Udry & J. Venturini * Instituto de Astrofisica de Canarias, La Laguna,

Tenerife, Spain E. Pallé, G. Nowak, I. Carleo, J. Orell-Miquel, R. Alonso, H. J. Deeg, E. Esparza-Borges, A. Fukui, F. Murgas, N. Narita & H. Parviainen * Departamento de Astrofisica,

Universidad de La Laguna, La Laguna, Tenerife, Spain E. Pallé, G. Nowak, J. Orell-Miquel, R. Alonso, H. J. Deeg, E. Esparza-Borges, F. Murgas & H. Parviainen * Space Research Institute,

Austrian Academy of Sciences, Graz, Austria A. Bonfanti, W. Baumjohann, P. E. Cubillos, L. Fossati & Ch. Helling * Sub-department of Astrophysics, Department of Physics, University of

Oxford, Oxford, UK O. Barragán * Centre for Exoplanet Science, SUPA School of Physics and Astronomy, University of St Andrews, St Andrews, UK T. G. Wilson & A. Collier Cameron *

Department of Physics, University of Warwick, Coventry, UK T. G. Wilson, M. Lafarga, D. R. Anderson, D. Bayliss, E. M. Bryant, S. Gill & D. Pollacco * Centre for Exoplanets and

Habitability, University of Warwick, Coventry, UK T. G. Wilson, M. Lafarga & D. R. Anderson * Center for Space and Habitability, University of Bern, Bern, Switzerland C. Broeg, Y.

Alibert, W. Benz, B.-O. Demory, A. Fortier, C. Mordasini & N. Schanche * Astrophysics Group, Lennard Jones Building, Keele University, Keele, UK P. F. L. Maxted * Dipartimento di Fisica,

Universita degli Studi di Torino, Torino, Italy D. Gandolfi & E. Goffo * Cavendish Laboratory, University of Cambridge, Cambridge, UK M. J. Hooton, D. Queloz & A. Tuson * Institute

of Astronomy, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University, Toruń, Poland G. Nowak * NASA Ames Research Center, Moffett Field, CA, USA D. Rapetti, J. D.

Twicken, S. B. Howell & J. M. Jenkins * Research Institute for Advanced Computer Science, Universities Space Research Association, Washington, DC, USA D. Rapetti * SETI Institute,

Mountain View, CA, USA J. D. Twicken * Institut de Ciencies de l’Espai (ICE-CSIC), Bellaterra, Spain J. C. Morales, G. Anglada-Escudé & I. Ribas * Institut d’Estudis Espacials de

Catalunya (IEEC), Barcelona, Spain J. C. Morales, G. Anglada-Escudé & I. Ribas * INAF - Osservatorio Astrofisico di Torino, Pino Torinese, Italy I. Carleo & P. E. Cubillos *

Instituto de Astrofísica e Ciências do Espaço, Universidade do Porto, Porto, Portugal V. Adibekyan * Departamento de Física e Astronomia, Faculdade de Ciências, Universidade do Porto, Porto,

Portugal V. Adibekyan * Mullard Space Science Laboratory, University College London, Dorking, UK A. Alqasim, E. M. Bryant, H. L. M. Osborne & V. Van Eylen * Instituto de Astrofísica de

Andalucía (IAA-CSIC), Granada, Spain P. J. Amado * European Space Research and Technology Centre (ESTEC), European Space Agency (ESA), Noordwijk, The Netherlands T. Bandy, M. N. Günther, K.

G. Isaak, N. Rando & F. Ratti * Admatis, Miskolc, Hungary T. Bárczy * Depto. de Astrofisica, Centro de Astrobiología (INTA-CSIC), Madrid, Spain D. Barrado Navascues * Instituto de

Astrofisica e Ciencias do Espaco, Universidade do Porto, Porto, Portugal S. C. C. Barros, O. D. S. Demangeon, N. C. Santos & S. G. Sousa * Departamento de Fisica e Astronomia, Faculdade

de Ciencias, Universidade do Porto, Porto, Portugal S. C. C. Barros, O. D. S. Demangeon & N. C. Santos * Université Grenoble Alpes, CNRS, IPAG, Grenoble, France X. Bonfils * INAF -

Osservatorio Astronomico di Padova, Padova, Italy L. Borsato, D. Magrin, V. Nascimbeni, G. Piotto & R. Ragazzoni * Department of Astronomy, California Institute of Technology, Pasadena,

CA, USA A. W. Boyle, D. R. Ciardi & F. Dai * Department of Astronomy, Stockholm University, AlbaNova University Center, Stockholm, Sweden A. Brandeker & G. Olofsson * Institute of

Planetary Research, German Aerospace Center (DLR), Berlin, Germany J. Cabrera, Sz. Csizmadia, A. Erikson, K. W. F. Lam, H. Rauer & A. M. S. Smith * Instituto de Astronomía, Universidad

Nacional Autónoma de México, Ciudad de México, Mexico S. Carrazco-Gaxiola & Y. Gómez Maqueo Chew * Department of Physics and Astronomy, Georgia State University, Atlanta, GA, USA S.

Carrazco-Gaxiola * RECONS Institute, Chambersburg, PA, USA S. Carrazco-Gaxiola * Center for Astrophysics | Harvard & Smithsonian, Cambridge, MA, USA D. Charbonneau, K. A. Collins, J.

Garcia-Mejia, D. W. Latham & S. N. Quinn * Université de Paris Cité, Institut de Physique du Globe de Paris, CNRS, Paris, France S. Charnoz * McDonald Observatory, The University of

Texas, Austin, TX, USA W. D. Cochran * Center for Planetary Systems Habitability, The University of Texas, Austin, TX, USA W. D. Cochran * Department of Physics and Astronomy, University of

Kansas, Lawrence, KS, USA I. J. M. Crossfield * Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, USA F. Dai * Centre for Mathematical

Sciences, Lund University, Lund, Sweden M. B. Davies * Aix Marseille Univ., CNRS, CNES, LAM, Marseille, France M. Deleuil & S. Hoyer * Astrobiology Research Unit, Université de Liège,

Liège, Belgium L. Delrez & M. Gillon * Space sciences, Technologies and Astrophysics Research (STAR) Institute, Université de Liège, Liège, Belgium L. Delrez, M. Stalport & V. Van

Grootel * Centre Vie dans l’Univers, Faculté des sciences, Université de Genève, Genève 4, Switzerland D. Ehrenreich * Space Telescope Science Institute, Baltimore, MD, USA B. Falk * Leiden

Observatory, University of Leiden, Leiden, The Netherlands M. Fridlund * Onsala Space Observatory, Department of Space, Earth and Environment, Chalmers University of Technology, Onsala,

Sweden M. Fridlund * Komaba Institute for Science, The University of Tokyo, Tokyo, Japan A. Fukui, T. Kodama & N. Narita * Thüringer Landessternwarte Tautenburg, Tautenburg, Germany E.

Goffo, E. W. Guenther & A. P. Hatzes * Department of Astrophysics, University of Vienna, Vienna, Austria M. Güdel & R. Ottensamer * Department of Multi-Disciplinary Sciences,

Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan K. Ikuta, T. Kagetani, J. P. D. Leon, M. Mori & N. Watanabe * Konkoly Observatory, HUN-REN Research Centre for

Astronomy and Earth Sciences, Budapest, Hungary L. L. Kiss * Institute of Physics, ELTE Eötvös Loránd University, Budapest, Hungary L. L. Kiss * Lund Observatory, Division of Astrophysics,

Department of Physics, Lund University, Lund, Sweden J. Korth * IMCCE, UMR8028 CNRS, Observatoire de Paris, PSL Univ., Sorbonne Univ., Paris, France J. Laskar * Institut d’Astrophysique de

Paris, UMR7095 CNRS, Université Pierre & Marie Curie, Paris, France A. Lecavelier des Etangs * Astrobiology Center, Tokyo, Japan J. H. Livingston & N. Narita * National Astronomical

Observatory of Japan, Tokyo, Japan J. H. Livingston * Department of Astronomical Science, The Graduate University for Advanced Studies, SOKENDAI, Tokyo, Japan J. H. Livingston * United

States Naval Observatory, Washington, DC, USA R. A. Matson * Max Planck Institute for Astronomy, Heidelberg, Germany E. C. Matthews * Instituto de Astronomía, Universidad Católica del Norte,

Antofagasta, Chile M. Moyano * INAF - Osservatorio Astrofisico di Catania, Catania, Italy M. Munari, I. Pagano & G. Scandariato * Institute of Optical Sensor Systems, German Aerospace

Center (DLR), Berlin, Germany G. Peter & I. Walter * Dipartimento di Fisica e Astronomia “Galileo Galilei”, Universita degli Studi di Padova, Padova, Italy G. Piotto, R. Ragazzoni & 

T. Zingales * Department of Physics, ETH Zurich, Zurich, Switzerland D. Queloz * Landessternwarte, Zentrum für Astronomie der Universität Heidelberg, Heidelberg, Germany A. Quirrenbach *

Zentrum für Astronomie und Astrophysik, Technische Universität Berlin, Berlin, Germany H. Rauer * Institut für Geologische Wissenschaften, Freie Universität Berlin, Berlin, Germany H. Rauer

* Astronomy Department, Wesleyan University, Middletown, CT, USA S. Redfield * Van Vleck Observatory, Wesleyan University, Middletown, CT, USA S. Redfield * Instituto de Astronomía,

Universidad Nacional Autónoma de México, Ensenada, Mexico L. Sabin * Department of Astronomy, University of Maryland, College Park, MD, USA N. Schanche * NASA Goddard Space Flight Center,

Greenbelt, MD, USA J. E. Schlieder * Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA S. Seager * Department of Aeronautics

and Astronautics, Massachusetts Institute of Technology, Cambridge, MA, USA S. Seager * Gothard Astrophysical Observatory, ELTE Eötvös Loránd University, Szombathely, Hungary Gy. M. Szabó *

HUN-REN-ELTE Exoplanet Research Group, Szombathely, Hungary Gy. M. Szabó * Institute of Astronomy, University of Cambridge, Cambridge, UK N. A. Walton * Department of Astrophysical Sciences,

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can also search for this author inPubMed Google Scholar * T. Zingales View author publications You can also search for this author inPubMed Google Scholar CONTRIBUTIONS R.Lu., H.P.Os.,

A.Le., E.Pa., A.Bo., O.Ba. and T.G.Wi. conceived the project and contributed notably to the writing of this manuscript. R.Lu. and H.P.Os. led the analysis of the photometric data. A.Le. led

the dynamical analysis of the system and developed the method with J.-B.De. to predict the orbits of the planets based on their resonant state within the chain. R.Lu., A.Bo. and O.Ba. led

the analysis of the radial velocity data and the stellar activity mitigation. T.G.Wi. led the stellar characterization with the help of V.Ad., S.G.So., A.Bo., V.V.Gr., S.Sa. and W.D.Co.

Y.Al. and J.A.Eg. led the analysis of the internal structures and L.Fo. and A.Bo. performed the atmospheric evolution simulations. D.Ra., J.D.Tw. and J.M.Je. improved the TESS data reduction

to recover the missing cadences affected by reflected light and high background. R.Lu., E.Pa. and G.No. planned and obtained the time for the observations with CARMENES and HARPS-N.

CARMENES observations were made possible by M.La., J.C.Mo., P.J.Am., A.Qu. and I.Ri. HARPS-N observations were made possible by I.Ca., J.O.-M., F.Mu., H.J.De., J.Ko., D.Ga., J.H.Li.,

W.D.Co., E.W.Gu., V.V.Ey., H.L.M.Os., S.Re., E.Go., F.Da. and K.W.F.La. High-resolution imaging observations from Palomar and Gemini North were made possible by A.W.Bo., D.R.Ci., I.J.M.Cr.,

S.B.Ho., E.Ma. and J.E.Sc. Ground-based photometric observations to catch the transit of planet f were made possible by the MuSCAT2 (R.Lu., E.Pa., N.Na., J.H.Li., K.Ik., E.E.-B., J.O.-M.,

N.Wa., F.Mu., G.No., A.Fu., H.Pa., M.Mo., T.Ka., J.P.D.Le. and T.Ko.), LCO (T.G.Wi., R.Lu., H.P.Os., E.Pa., A.Le., A.Tu., M.J.Ho., Y.Al. and D.Ga.), NGTS (H.P.Os., S.Gi., D.Ba., D.R.An.,

M.Mo., A.M.S.Sm., E.M.Br. and S.Ud.), Tierras (J.G.-M. and D.Ch.), SAINT-EX (N.Sc., Y.G.M.Ch., L.Sa., S.C.-G. and B.-O.De.) and MuSCAT3 (N.Na., J.H.Li., K.Ik., N.Wa., A.Fu., M.Mo., T.Ka.,

J.P.D.Le. and T.Ko.) instruments. The remaining authors provided key contributions to the development of the TESS and CHEOPS mission. All authors read and commented on the manuscript and

helped with its revision. CORRESPONDING AUTHOR Correspondence to R. Luque. ETHICS DECLARATIONS COMPETING INTERESTS The authors declare no competing interests. PEER REVIEW PEER REVIEW

INFORMATION _Nature_ thanks Eric Agol and the other, anonymous, reviewer(s) for their contribution to the peer review of this work. ADDITIONAL INFORMATION PUBLISHER’S NOTE Springer Nature

remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. EXTENDED DATA FIGURES AND TABLES EXTENDED DATA FIG. 1 TRANSIT DURATION VERSUS TRANSIT

DEPTH FOR ALL UNASSIGNED TRANSITS IN THE TESS DATA. TESS Sector 23 and Sector 49 are shown as different colours. The numbers above each transit denote the mid-transit time in TJD. Contours

represent percentile levels, the innermost one corresponding to the 50th percentile and the outermost to the 99th percentile by increments of 10%. The transit of planet f in PLD photometry

is marked with * to indicate that its properties are heavily affected by pretransit systematic noise. EXTENDED DATA FIG. 2 GENERALIZED THREE-BODY LAPLACE ANGLES FOR KNOWN SYSTEMS IN RESONANT

CHAINS. Included are the Galilean satellites Kepler-60 (refs. 12,115), Kepler-80 (ref. 159), K2-138 (ref. 112), Kepler-223 (ref. 110), TRAPPIST-1 (ref. 13) and TOI-178 (ref. 10).

Measurements belonging to the same system are marked with the same colour. The line marks the observed distance to the theorized equilibrium (marked with a circle). The distances are

estimated at the zeroth order in eccentricity110,111. For most systems, a single estimation of the generalized Laplace angle is made, whereas ref. 110 made an estimation for each Kepler

quarter. EXTENDED DATA FIG. 3 OBSERVED DISTANCE FROM THE EQUILIBRIUM FOR ALL THE SIMULATED SCENARIOS IN WHICH PLANETS F AND G CONTINUE THE RESONANT CHAIN. The _y_ axis is converted to the

mean peak-to-peak amplitude from the generalized three-body Laplace angle using the following expression: mean \(({\mathcal{A}}({\varPsi }_{i}))=C/4\). Case A2 remains the one that has the

potential to be the closest to an equilibrium. EXTENDED DATA FIG. 4 RESULTS FROM THE GROUND-BASED CAMPAIGN TO DETECT HD 110067 F. A, ΔWAIC for each of the constrained period bins when

compared with a transit-free model. B,C, Best-fit decorrelated photometry with (B) and without (C) a transit model. Each light curve from each telescope has been offset for clarity. Error

bars represent 1_σ_ uncertainties. EXTENDED DATA FIG. 5 RESULTS FROM THE TWO RADIAL VELOCITY ANALYSES TO MEASURE THE MASS OF EACH OF THE PLANETS IN THE HD 110067 SYSTEM. Each histogram

represents the posterior density function (pdf) of the radial velocity semiamplitudes as inferred from method I (red) and method II (blue). The area underneath each histogram is normalized

to unity. EXTENDED DATA FIG. 6 GAS MASS FRACTION OF THE HD 110067 PLANETS AS A FUNCTION OF THEIR EQUILIBRIUM TEMPERATURE. We infer two values per planet by assuming the different planetary

masses from our method I (red) and method II (blue) radial velocity analyses. The boxes, orange lines, green triangles and red stars represent, respectively, the 25th and 75th percentiles,

medians, means and modes of the posterior distributions. The opacity of the vertical lines is proportional to the posterior distribution. SUPPLEMENTARY INFORMATION SUPPLEMENTARY INFORMATION

The file includes Supplementary Figs. 1–12 and Supplementary Tables 1–5. The figures include: full detrended CHEOPS photometry of all visits (Fig. S1); high-resolution imaging of HD 110067

excluding nearby stellar companions (Fig. S2); potential orbital solutions from the analysis of the two duo transit and the two mono transit events (Fig. S3); properties of known resonant

chains in terms of their period ratios (Fig. S4); a numerical integration of the best-fit solution of the full six-body resonant chain demonstrating the dynamical stability of the system

(Fig. S5); original and reprocessed TESS Sector 23 data confirming the existence of planets f and g (Fig. S6); periodograms of the radial velocity and derived spectral indicators of the

CARMENES and HARPS-N data (Figs. S7 and S8); best-fit solution of the radial velocity model from method I (Fig. S9); cross-validation analysis of the GP fit used in the radial velocity model

from method II (Fig. S10); periodogram of radial velocity residuals after the fit demonstrating the absence of further signals in the data (Fig. S11); and corner plots of the most relevant

parameters from the photometric fit (Fig. S12). The tables include the parameters, priors and posterior distributions of our photometric model (Table S1), radial velocity models using method

I (Tables S2 and S3) and method II (Table S4), and internal structure model (Table S5). RIGHTS AND PERMISSIONS Springer Nature or its licensor (e.g. a society or other partner) holds

exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely

governed by the terms of such publishing agreement and applicable law. Reprints and permissions ABOUT THIS ARTICLE CITE THIS ARTICLE Luque, R., Osborn, H.P., Leleu, A. _et al._ A resonant

sextuplet of sub-Neptunes transiting the bright star HD 110067. _Nature_ 623, 932–937 (2023). https://doi.org/10.1038/s41586-023-06692-3 Download citation * Received: 02 May 2023 * Accepted:

28 September 2023 * Published: 29 November 2023 * Issue Date: 30 November 2023 * DOI: https://doi.org/10.1038/s41586-023-06692-3 SHARE THIS ARTICLE Anyone you share the following link with

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