From Earths to super-Earths: five new small planets transiting M dwarf stars

Jonathan Gomez Barrientos; Heather A. Knutson; Morgan Saidel; Michael Greklek-McKeon; W. Garrett Levine; Nicholas Saunders; Howard Isaacson; Renyu Hu; Karen A. Collins; David R. Ciardi; Polina A. Budnikova; Dmitry V. Cheryasov; Samuel W. Yee; Diogo Souto; Aida Behmard; Akihiko Fukui; Avi Shporer; Akanksha Khandelwal; Bob Massey; Brice-Oliver Demory; Catherine A. Clark; Chris Stockdale; Emily A. Gilbert; Enric Palle; Francis P. Wilkin; Felipe Murgas; Francis Zong Lang; Ilse Plauchu-Frayn; Jessie L. Christiansen; Jon M. Jenkins; Joseph D. Twicken; Keith Horne; Michaël Gillon; Monika Lendl; Michael B. Lund; Norio Narita; Pam Rowden; Ramotholo Sefako; Richard P. Schwarz; Steven Giacalone; Urs Schroffenegger; Yilen Gómez Maqueo Chew

doi:10.3847/1538-3881/ae246f

From Earths to super-Earths: five new small planets transiting M dwarf stars

Jonathan Gomez Barrientos^*, Heather A. Knutson, Morgan Saidel, Michael Greklek-McKeon, W. Garrett Levine, Nicholas Saunders, Howard Isaacson, Renyu Hu, Karen A. Collins, David R. Ciardi, Polina A. Budnikova, Dmitry V. Cheryasov, Samuel W. Yee, Diogo Souto, Aida Behmard, Akihiko Fukui, Avi Shporer, Akanksha Khandelwal, Bob Massey, Brice-Oliver DemoryCatherine A. Clark, Chris Stockdale, Emily A. Gilbert, Enric Palle, Francis P. Wilkin, Felipe Murgas, Francis Zong Lang, Ilse Plauchu-Frayn, Jessie L. Christiansen, Jon M. Jenkins, Joseph D. Twicken, Keith Horne, Michaël Gillon, Monika Lendl, Michael B. Lund, Norio Narita, Pam Rowden, Ramotholo Sefako, Richard P. Schwarz, Steven Giacalone, Urs Schroffenegger, Yilen Gómez Maqueo Chew

^*Corresponding author for this work

Research output: Contribution to journal › Article › peer-review

Abstract

Earth-sized planets transiting M dwarf stars present one of the best opportunities with current facilities for studying the atmospheric and bulk compositions of terrestrial worlds. Here, we statistically validate five new transiting Earth and super-Earth sized planets orbiting M dwarf stars using a combination of light curves from the Transiting Exoplanet Survey Satellite, multicolor observations from Palomar and Las Cumbres Observatory, high-resolution imaging, and stellar spectroscopy. The sample includes TOI-5716 b, an Earth-sized planet (R_p = 0.96 ± 0.05 R_⊕) with a 6.766 day orbit around a metal-poor thin-disk star ([Fe/H] = −0.54 ± 0.10); TOI-5728 b, a super-Earth (R_p = 1.31 ± 0.05 R_⊕) on an 11.497 day orbit; and TOI-5736 b, a larger planet (Rp = 1.56 ± 0.07 R_⊕) with an ultrashort period of just 0.649 days. We also statistically validate a multiplanet system, TOI-5489, hosting two similarly sized super-Earths: TOI-5489 b (R_p = 1.40 ± 0.05 R_⊕) and TOI-5489 c (R_p = 1.28 ± 0.07 R_⊕) with orbital periods of 3.152 and 4.921 days, respectively. Due to their longer orbital periods, TOI-5716 b and TOI-5728 b both have equilibrium temperatures ≤ 400 K, making them useful test cases for studies of atmospheric mass loss. If TOI-5728 b is confirmed to have an Earth-like bulk composition, it would join the very small sample of rocky planets orbiting mid-to-late M dwarfs that lie below the cosmic shoreline and therefore may have retained high mean molecular weight atmospheres.

Original language	English
Article number	99
Number of pages	14
Journal	Astronomical Journal
Volume	171
Issue number	2
Early online date	19 Jan 2026
DOIs	https://doi.org/10.3847/1538-3881/ae246f
Publication status	Published - 1 Feb 2026

Keywords

Infrared photometry
Transits
Extrasolar rocky planets

Access to Document

10.3847/1538-3881/ae246fLicence: CC BY

Barrientos_2026_AJ_From-Earths-to-super-Earths_CC
© 2026. The Author(s). Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
Final published version, 3.4 MBLicence: CC BY

Cite this

Barrientos, J. G., Knutson, H. A., Saidel, M., Greklek-McKeon, M., Levine, W. G., Saunders, N., Isaacson, H., Hu, R., Collins, K. A., Ciardi, D. R., Budnikova, P. A., Cheryasov, D. V., Yee, S. W., Souto, D., Behmard, A., Fukui, A., Shporer, A., Khandelwal, A., Massey, B., ... Chew, Y. G. M. (2026). From Earths to super-Earths: five new small planets transiting M dwarf stars. Astronomical Journal, 171(2), Article 99. https://doi.org/10.3847/1538-3881/ae246f

@article{01fa17c5ffbe458da0ab173eadaec8d3,

title = "From Earths to super-Earths: five new small planets transiting M dwarf stars",

abstract = "Earth-sized planets transiting M dwarf stars present one of the best opportunities with current facilities for studying the atmospheric and bulk compositions of terrestrial worlds. Here, we statistically validate five new transiting Earth and super-Earth sized planets orbiting M dwarf stars using a combination of light curves from the Transiting Exoplanet Survey Satellite, multicolor observations from Palomar and Las Cumbres Observatory, high-resolution imaging, and stellar spectroscopy. The sample includes TOI-5716 b, an Earth-sized planet (Rp = 0.96 ± 0.05 R⊕) with a 6.766 day orbit around a metal-poor thin-disk star ([Fe/H] = −0.54 ± 0.10); TOI-5728 b, a super-Earth (Rp = 1.31 ± 0.05 R⊕) on an 11.497 day orbit; and TOI-5736 b, a larger planet (Rp = 1.56 ± 0.07 R⊕) with an ultrashort period of just 0.649 days. We also statistically validate a multiplanet system, TOI-5489, hosting two similarly sized super-Earths: TOI-5489 b (Rp = 1.40 ± 0.05 R⊕) and TOI-5489 c (Rp = 1.28 ± 0.07 R⊕) with orbital periods of 3.152 and 4.921 days, respectively. Due to their longer orbital periods, TOI-5716 b and TOI-5728 b both have equilibrium temperatures ≤ 400 K, making them useful test cases for studies of atmospheric mass loss. If TOI-5728 b is confirmed to have an Earth-like bulk composition, it would join the very small sample of rocky planets orbiting mid-to-late M dwarfs that lie below the cosmic shoreline and therefore may have retained high mean molecular weight atmospheres.",

keywords = "Infrared photometry, Transits, Extrasolar rocky planets",

author = "Barrientos, \{Jonathan Gomez\} and Knutson, \{Heather A.\} and Morgan Saidel and Michael Greklek-McKeon and Levine, \{W. Garrett\} and Nicholas Saunders and Howard Isaacson and Renyu Hu and Collins, \{Karen A.\} and Ciardi, \{David R.\} and Budnikova, \{Polina A.\} and Cheryasov, \{Dmitry V.\} and Yee, \{Samuel W.\} and Diogo Souto and Aida Behmard and Akihiko Fukui and Avi Shporer and Akanksha Khandelwal and Bob Massey and Brice-Oliver Demory and Clark, \{Catherine A.\} and Chris Stockdale and Gilbert, \{Emily A.\} and Enric Palle and Wilkin, \{Francis P.\} and Felipe Murgas and Lang, \{Francis Zong\} and Ilse Plauchu-Frayn and Christiansen, \{Jessie L.\} and Jenkins, \{Jon M.\} and Twicken, \{Joseph D.\} and Keith Horne and Micha{\"e}l Gillon and Monika Lendl and Lund, \{Michael B.\} and Norio Narita and Pam Rowden and Ramotholo Sefako and Schwarz, \{Richard P.\} and Steven Giacalone and Urs Schroffenegger and Chew, \{Yilen G{\'o}mez Maqueo\}",

note = "Funding: The authors acknowledge support from the Swiss National Science Foundation SPIRIT-216537 and the Centre for Space and Habitability (CSH) of the University of Bern. Part of this work received support from the National Centre for Competence in Research Planets, supported by the Swiss National Science Foundation (SNSF). Y.G.M.C. and A.K. are partially supported by UNAM PAPIIT-IG101224. B.-O.D. acknowledges support from the Swiss State Secretariat for Education, Research and Innovation (SERI) under contract No. MB22.00046. We acknowledge financial support from the Agencia Estatal de Investigaci{\'o}n of the Ministerio de Ciencia e Innovaci{\'o}n MCIN/AEI/10.13039/501100011033 and the ERDF “A way of making Europe” through project PID2021-125627OB-C32, and from the Centre of Excellence “Severo Ochoa” award to the Instituto de Astrofisica de Canarias. This material is based upon work supported by the National Science Foundation Graduate Research Fellowship Program under grant No. DGE-1745301. F.M. acknowledges the financial support from the Agencia Estatal de Investigaci{\'o}n del Ministerio de Ciencia, Innovaci{\'o}n y Universidades (MCIU/AEI) through grant PID2023-152906NA-I00. W.G.L. gratefully acknowledges support from the Department of Defense{\textquoteright}s National Defense Science and Engineering Graduate (NDSEG) Fellowship. W.G.L. also thanks the LSST-DA Data Science Fellowship Program, which is funded by LSST-DA, the Brinson Foundation, the WoodNext Foundation, and the Research Corporation for Science Advancement Foundation; his participation in the program has benefited this work. M.L. acknowledges support of the Swiss National Science Foundation under grant no. PCEFP2194576. The contribution of M.L. has been carried out within the framework of the NCCR Planets supported by the Swiss National Science Foundation under grant 51NF40205606. This work is partly supported by JSPS KAKENHI grant No. JP24H00017 and JSPS Bilateral Program No. JPJSBP120249910. Y.G.M.C. and B.-O. D. acknowledge support from the Swiss National Science Foundation (IZSTZ0216537). D.S. acknowledges support from the Foundation for Research and Technological Innovation Support of the State of Sergipe (FAPITEC/SE) and the National Council for Scientific and Technological Development (CNPq), under grant Nos. 794017/2013 and 444372/2024-5. D.R.C. acknowledges partial support from NASA grant 182XRP182-0007.",

year = "2026",

month = feb,

day = "1",

doi = "10.3847/1538-3881/ae246f",

language = "English",

volume = "171",

journal = "Astronomical Journal",

issn = "0004-6256",

publisher = "American Astronomical Society",

number = "2",

}

Barrientos, JG, Knutson, HA, Saidel, M, Greklek-McKeon, M, Levine, WG, Saunders, N, Isaacson, H, Hu, R, Collins, KA, Ciardi, DR, Budnikova, PA, Cheryasov, DV, Yee, SW, Souto, D, Behmard, A, Fukui, A, Shporer, A, Khandelwal, A, Massey, B, Demory, B-O, Clark, CA, Stockdale, C, Gilbert, EA, Palle, E, Wilkin, FP, Murgas, F, Lang, FZ, Plauchu-Frayn, I, Christiansen, JL, Jenkins, JM, Twicken, JD, Horne, K, Gillon, M, Lendl, M, Lund, MB, Narita, N, Rowden, P, Sefako, R, Schwarz, RP, Giacalone, S, Schroffenegger, U & Chew, YGM 2026, 'From Earths to super-Earths: five new small planets transiting M dwarf stars', Astronomical Journal, vol. 171, no. 2, 99. https://doi.org/10.3847/1538-3881/ae246f

TY - JOUR

T1 - From Earths to super-Earths

T2 - five new small planets transiting M dwarf stars

AU - Barrientos, Jonathan Gomez

AU - Knutson, Heather A.

AU - Saidel, Morgan

AU - Greklek-McKeon, Michael

AU - Levine, W. Garrett

AU - Saunders, Nicholas

AU - Isaacson, Howard

AU - Hu, Renyu

AU - Collins, Karen A.

AU - Ciardi, David R.

AU - Budnikova, Polina A.

AU - Cheryasov, Dmitry V.

AU - Yee, Samuel W.

AU - Souto, Diogo

AU - Behmard, Aida

AU - Fukui, Akihiko

AU - Shporer, Avi

AU - Khandelwal, Akanksha

AU - Massey, Bob

AU - Demory, Brice-Oliver

AU - Clark, Catherine A.

AU - Stockdale, Chris

AU - Gilbert, Emily A.

AU - Palle, Enric

AU - Wilkin, Francis P.

AU - Murgas, Felipe

AU - Lang, Francis Zong

AU - Plauchu-Frayn, Ilse

AU - Christiansen, Jessie L.

AU - Jenkins, Jon M.

AU - Twicken, Joseph D.

AU - Horne, Keith

AU - Gillon, Michaël

AU - Lendl, Monika

AU - Lund, Michael B.

AU - Narita, Norio

AU - Rowden, Pam

AU - Sefako, Ramotholo

AU - Schwarz, Richard P.

AU - Giacalone, Steven

AU - Schroffenegger, Urs

AU - Chew, Yilen Gómez Maqueo

N1 - Funding: The authors acknowledge support from the Swiss National Science Foundation SPIRIT-216537 and the Centre for Space and Habitability (CSH) of the University of Bern. Part of this work received support from the National Centre for Competence in Research Planets, supported by the Swiss National Science Foundation (SNSF). Y.G.M.C. and A.K. are partially supported by UNAM PAPIIT-IG101224. B.-O.D. acknowledges support from the Swiss State Secretariat for Education, Research and Innovation (SERI) under contract No. MB22.00046. We acknowledge financial support from the Agencia Estatal de Investigación of the Ministerio de Ciencia e Innovación MCIN/AEI/10.13039/501100011033 and the ERDF “A way of making Europe” through project PID2021-125627OB-C32, and from the Centre of Excellence “Severo Ochoa” award to the Instituto de Astrofisica de Canarias. This material is based upon work supported by the National Science Foundation Graduate Research Fellowship Program under grant No. DGE-1745301. F.M. acknowledges the financial support from the Agencia Estatal de Investigación del Ministerio de Ciencia, Innovación y Universidades (MCIU/AEI) through grant PID2023-152906NA-I00. W.G.L. gratefully acknowledges support from the Department of Defense’s National Defense Science and Engineering Graduate (NDSEG) Fellowship. W.G.L. also thanks the LSST-DA Data Science Fellowship Program, which is funded by LSST-DA, the Brinson Foundation, the WoodNext Foundation, and the Research Corporation for Science Advancement Foundation; his participation in the program has benefited this work. M.L. acknowledges support of the Swiss National Science Foundation under grant no. PCEFP2194576. The contribution of M.L. has been carried out within the framework of the NCCR Planets supported by the Swiss National Science Foundation under grant 51NF40205606. This work is partly supported by JSPS KAKENHI grant No. JP24H00017 and JSPS Bilateral Program No. JPJSBP120249910. Y.G.M.C. and B.-O. D. acknowledge support from the Swiss National Science Foundation (IZSTZ0216537). D.S. acknowledges support from the Foundation for Research and Technological Innovation Support of the State of Sergipe (FAPITEC/SE) and the National Council for Scientific and Technological Development (CNPq), under grant Nos. 794017/2013 and 444372/2024-5. D.R.C. acknowledges partial support from NASA grant 182XRP182-0007.

PY - 2026/2/1

Y1 - 2026/2/1

N2 - Earth-sized planets transiting M dwarf stars present one of the best opportunities with current facilities for studying the atmospheric and bulk compositions of terrestrial worlds. Here, we statistically validate five new transiting Earth and super-Earth sized planets orbiting M dwarf stars using a combination of light curves from the Transiting Exoplanet Survey Satellite, multicolor observations from Palomar and Las Cumbres Observatory, high-resolution imaging, and stellar spectroscopy. The sample includes TOI-5716 b, an Earth-sized planet (Rp = 0.96 ± 0.05 R⊕) with a 6.766 day orbit around a metal-poor thin-disk star ([Fe/H] = −0.54 ± 0.10); TOI-5728 b, a super-Earth (Rp = 1.31 ± 0.05 R⊕) on an 11.497 day orbit; and TOI-5736 b, a larger planet (Rp = 1.56 ± 0.07 R⊕) with an ultrashort period of just 0.649 days. We also statistically validate a multiplanet system, TOI-5489, hosting two similarly sized super-Earths: TOI-5489 b (Rp = 1.40 ± 0.05 R⊕) and TOI-5489 c (Rp = 1.28 ± 0.07 R⊕) with orbital periods of 3.152 and 4.921 days, respectively. Due to their longer orbital periods, TOI-5716 b and TOI-5728 b both have equilibrium temperatures ≤ 400 K, making them useful test cases for studies of atmospheric mass loss. If TOI-5728 b is confirmed to have an Earth-like bulk composition, it would join the very small sample of rocky planets orbiting mid-to-late M dwarfs that lie below the cosmic shoreline and therefore may have retained high mean molecular weight atmospheres.

AB - Earth-sized planets transiting M dwarf stars present one of the best opportunities with current facilities for studying the atmospheric and bulk compositions of terrestrial worlds. Here, we statistically validate five new transiting Earth and super-Earth sized planets orbiting M dwarf stars using a combination of light curves from the Transiting Exoplanet Survey Satellite, multicolor observations from Palomar and Las Cumbres Observatory, high-resolution imaging, and stellar spectroscopy. The sample includes TOI-5716 b, an Earth-sized planet (Rp = 0.96 ± 0.05 R⊕) with a 6.766 day orbit around a metal-poor thin-disk star ([Fe/H] = −0.54 ± 0.10); TOI-5728 b, a super-Earth (Rp = 1.31 ± 0.05 R⊕) on an 11.497 day orbit; and TOI-5736 b, a larger planet (Rp = 1.56 ± 0.07 R⊕) with an ultrashort period of just 0.649 days. We also statistically validate a multiplanet system, TOI-5489, hosting two similarly sized super-Earths: TOI-5489 b (Rp = 1.40 ± 0.05 R⊕) and TOI-5489 c (Rp = 1.28 ± 0.07 R⊕) with orbital periods of 3.152 and 4.921 days, respectively. Due to their longer orbital periods, TOI-5716 b and TOI-5728 b both have equilibrium temperatures ≤ 400 K, making them useful test cases for studies of atmospheric mass loss. If TOI-5728 b is confirmed to have an Earth-like bulk composition, it would join the very small sample of rocky planets orbiting mid-to-late M dwarfs that lie below the cosmic shoreline and therefore may have retained high mean molecular weight atmospheres.

KW - Infrared photometry

KW - Transits

KW - Extrasolar rocky planets

U2 - 10.3847/1538-3881/ae246f

DO - 10.3847/1538-3881/ae246f

M3 - Article

SN - 0004-6256

VL - 171

JO - Astronomical Journal

JF - Astronomical Journal

IS - 2

M1 - 99

ER -

From Earths to super-Earths: five new small planets transiting M dwarf stars

Abstract

Keywords

Access to Document

Fingerprint

Cite this