Two Earth-size Planets and an Earth-size Candidate Transiting the nearby Star HD 101581*
Abstract We report the validation of multiple planets transiting the nearby ( d = 12.8 pc) K5V dwarf HD 101581 (GJ 435, TOI–6276, TIC 397362481). This system consists of at least two Earth-size planets whose orbits are near a mutual 4:3 mean-motion resonance, HD 101581 b ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msub> <mml:mrow> <mml:mi>R</mml:mi> </mml:mrow> <mml:mrow> <mml:mi>p</mml:mi> </mml:mrow> </mml:msub> <mml:mo>=</mml:mo> <mml:msubsup> <mml:mrow> <mml:mn>0.956</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>0.061</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> <mml:mn>0.063</mml:mn> </mml:mrow> </mml:msubsup> <mml:mspace width="0.25em"/> <mml:msub> <mml:mrow> <mml:mi>R</mml:mi> </mml:mrow> <mml:mrow> <mml:mo>⊕</mml:mo> </mml:mrow> </mml:msub> </mml:math> , P = 4.47 days) and HD 101581c ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msub> <mml:mrow> <mml:mi>R</mml:mi> </mml:mrow> <mml:mrow> <mml:mi>p</mml:mi> </mml:mrow> </mml:msub> <mml:mo>=</mml:mo> <mml:msubsup> <mml:mrow> <mml:mn>0.990</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>0.070</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> <mml:mn>0.070</mml:mn> </mml:mrow> </mml:msubsup> <mml:mspace width="0.25em"/> <mml:msub> <mml:mrow> <mml:mi>R</mml:mi> </mml:mrow> <mml:mrow> <mml:mo>⊕</mml:mo> </mml:mrow> </mml:msub> </mml:math> , P = 6.21 days). Both planets were discovered in Sectors 63 and 64 TESS observations and statistically validated with supporting ground-based follow-up. We also identify a signal that probably originates from a third transiting planet, TOI-6276.03 ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msub> <mml:mrow> <mml:mi>R</mml:mi> </mml:mrow> <mml:mrow> <mml:mi>p</mml:mi> </mml:mrow> </mml:msub> <mml:mo>=</mml:mo> <mml:msubsup> <mml:mrow> <mml:mn>0.982</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>0.098</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> <mml:mn>0.114</mml:mn> </mml:mrow> </mml:msubsup> <mml:mspace width="0.25em"/> <mml:msub> <mml:mrow> <mml:mi>R</mml:mi> </mml:mrow> <mml:mrow> <mml:mo>⊕</mml:mo> </mml:mrow> </mml:msub> </mml:math> , P = 7.87 days). These planets are remarkably uniform in size and their orbits are evenly spaced, representing a prime example of the “peas-in-a-pod” architecture seen in other compact multiplanet systems. At V = 7.77, HD 101581 is the brightest star known to host multiple transiting planets smaller than 1.5 R ⊕ . HD 101581 is a promising system for atmospheric characterization and comparative planetology of small planets.
Authors
- Tansu Daylan (ORCID: https://orcid.org/0000-0002-6939-9211)
- J. Doty (ORCID: https://orcid.org/0000-0003-2996-8421)
- Jon M. Jenkins (ORCID: https://orcid.org/0000-0002-4715-9460)
- Michelle Kunimoto (ORCID: https://orcid.org/0000-0001-9269-8060)
- Robert A. Wittenmyer (ORCID: https://orcid.org/0000-0001-9957-9304)
- H. P. Osborn (ORCID: https://orcid.org/0000-0002-4047-4724)
- Joseph D. Twicken (ORCID: https://orcid.org/0000-0002-6778-7552)
- Rafael Brahm (ORCID: https://orcid.org/0000-0002-9158-7315)
- S. J. O’Toole (ORCID: https://orcid.org/0000-0003-2839-8527)
- E. W. Guenther (ORCID: https://orcid.org/0000-0002-9130-6747)
- R. Paul Butler (ORCID: https://orcid.org/0000-0003-1305-3761)
- Karen A. Collins (ORCID: https://orcid.org/0000-0001-6588-9574)
- Natalie R. Hinkel (ORCID: https://orcid.org/0000-0003-0595-5132)
- Steve B. Howell (ORCID: https://orcid.org/0000-0002-2532-2853)
- Shubham Kanodia (ORCID: https://orcid.org/0000-0001-8401-4300)
- Ján Janík (ORCID: https://orcid.org/0000-0002-6384-0184)
- Matías R. Díaz (ORCID: https://orcid.org/0000-0002-2100-3257)
- Stephen A. Shectman (ORCID: https://orcid.org/0000-0002-8681-6136)
- Sara Seager (ORCID: https://orcid.org/0000-0002-6892-6948)
- P. Kábath (ORCID: https://orcid.org/0000-0002-1623-5352)
- Jeffrey D. Crane (ORCID: https://orcid.org/0000-0002-5226-787X)
- Richard P. Schwarz (ORCID: https://orcid.org/0000-0001-8227-1020)
- Johanna Teske (ORCID: https://orcid.org/0009-0008-2801-5040)
- Martin Paegert (ORCID: https://orcid.org/0000-0001-8120-7457)
- H. R. A. Jones (ORCID: https://orcid.org/0000-0003-0433-3665)
- Colin Littlefield (ORCID: https://orcid.org/0000-0001-7746-5795)
- Andrew Vanderburg (ORCID: https://orcid.org/0000-0001-7246-5438)
- G. Ricker (ORCID: https://orcid.org/0000-0003-2058-6662)
- Alexander Venner (ORCID: https://orcid.org/0000-0002-8400-1646)
- Knicole D. Colón (ORCID: https://orcid.org/0000-0001-8020-7121)
- Kevin I. Collins (ORCID: https://orcid.org/0000-0003-2781-3207)
- Pavel Pintr
- Zifan Lin (ORCID: https://orcid.org/0000-0003-0525-9647)
- Jonathan Horner (ORCID: https://orcid.org/0000-0002-1160-7970)
- Avi Shporer (ORCID: https://orcid.org/0000-0002-1836-3120)
- Jeremy Bailey (ORCID: https://orcid.org/0000-0002-5726-7000)
- Sarah Millholland (ORCID: https://orcid.org/0000-0003-3130-2282)
- Brad Carter (ORCID: https://orcid.org/0000-0003-0035-8769)
- David R. Ciardi (ORCID: https://orcid.org/0000-0002-5741-3047)
- Fabo Feng (ORCID: https://orcid.org/0000-0001-6039-0555)
- Sharon X. Wang (ORCID: https://orcid.org/0000-0002-6937-9034)
- Keivan G. Stassun (ORCID: https://orcid.org/0000-0002-3481-9052)
- Jennifer Burt (ORCID: https://orcid.org/0000-0002-0040-6815)
- L. Vanzi
- Joshua N. Winn (ORCID: https://orcid.org/0000-0002-4265-047X)
- Gregor Srdoč
Publication Details
- Journal
- The Astronomical Journal
- Published
- 2024-12-20
- DOI
- https://doi.org/10.3847/1538-3881/ad9266
- Citations
- 3
- Primary Topic
- Stellar, planetary, and galactic studies
- Type
- article
- Field-Weighted Citation Impact
- 0.99
Funders
- National Science Foundation
- National Aeronautics and Space Administration
- George Mason University
- Vanderbilt University
- California Institute of Technology
- University of Louisville
- University of Texas at Austin
- Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung
- University of New South Wales
- University of Southern Queensland
- Ministry of Science, ICT and Future Planning
- Korea Astronomy and Space Science Institute
- European Southern Observatory
- Nanjing University
- Masarykova Univerzita
- Ministério da Ciência, Tecnologia, Inovações e Comunicações
- Agencia Nacional de Investigación y Desarrollo
- Ames Research Center
- Jet Propulsion Laboratory
- Science Mission Directorate