The Astronomical Journal (Jan 2025)
The Compositions of Rocky Planets in Close-in Orbits Tend to Be Earth-like
- Casey L. Brinkman,
- Lauren M. Weiss,
- Daniel Huber,
- Rena A. Lee,
- Jared Kolecki,
- Gwyneth Tenn,
- Jingwen Zhang,
- Suchitra Narayanan,
- Alex S. Polanski,
- Fei Dai,
- Jacob L. Bean,
- Corey Beard,
- Madison Brady,
- Max Brodheim,
- Matt Brown,
- Ashley Chontos,
- William Deich,
- Jerry Edelstein,
- Benjamin J. Fulton,
- Steven Giacalone,
- Steven R. Gibson,
- Gregory J. Gilbert,
- Samuel Halverson,
- Luke Handley,
- Grant M. Hill,
- Rae Holcomb,
- Bradford Holden,
- Aaron Householder,
- Andrew W. Howard,
- Howard Isaacson,
- Stephen Kaye,
- Russ R. Laher,
- Kyle Lanclos,
- J. M. Joel Ong,
- Joel Payne,
- Erik A. Petigura,
- Daria Pidhorodetska,
- Claire Poppett,
- Arpita Roy,
- Ryan Rubenzahl,
- Nicholas Saunders,
- Christian Schwab,
- Andreas Seifahrt,
- Abby P. Shaum,
- Martin M. Sirk,
- Chris Smith,
- Roger Smith,
- Guđmundur Stefánsson,
- Julian Stürmer,
- Jim Thorne,
- Emma V. Turtelboom,
- Dakotah Tyler,
- John Valliant,
- Judah Van Zandt,
- Josh Walawender,
- Samuel W. Yee,
- Sherry Yeh,
- Jon Zink
Affiliations
- Casey L. Brinkman
- ORCiD
- Institute for Astronomy, University of Hawai‘i , 2680 Woodlawn Drive, Honolulu, HI 96822, USA ; [email protected]; McGill University , Trottier Space Institute, 3550 rue University, Montreal, QC H3A 2A7, Canada
- Lauren M. Weiss
- ORCiD
- Department of Physics and Astronomy, University of Notre Dame , Notre Dame, IN 46556, USA
- Daniel Huber
- ORCiD
- Institute for Astronomy, University of Hawai‘i , 2680 Woodlawn Drive, Honolulu, HI 96822, USA ; [email protected]; Sydney Institute for Astronomy (SIfA), School of Physics, University of Sydney , NSW 2006, Australia
- Rena A. Lee
- ORCiD
- Institute for Astronomy, University of Hawai‘i , 2680 Woodlawn Drive, Honolulu, HI 96822, USA ; [email protected]
- Jared Kolecki
- Department of Physics and Astronomy, University of Notre Dame , Notre Dame, IN 46556, USA
- Gwyneth Tenn
- ORCiD
- Punahou School , 1601 Punahou Street, Honolulu, HI 96822, USA
- Jingwen Zhang
- ORCiD
- Institute for Astronomy, University of Hawai‘i , 2680 Woodlawn Drive, Honolulu, HI 96822, USA ; [email protected]
- Suchitra Narayanan
- ORCiD
- Institute for Astronomy, University of Hawai‘i , 2680 Woodlawn Drive, Honolulu, HI 96822, USA ; [email protected]
- Alex S. Polanski
- ORCiD
- Department of Physics and Astronomy, University of Kansas , Lawrence, KS 66045, USA; Lowell Observatory , 1400 W Mars Hill Road, Flagstaff, AZ, USA 86001, USA
- Fei Dai
- ORCiD
- Institute for Astronomy, University of Hawai‘i , 2680 Woodlawn Drive, Honolulu, HI 96822, USA ; [email protected]
- Jacob L. Bean
- ORCiD
- Department of Astronomy & Astrophysics, University of Chicago , 5640 S. Ellis Avenue, Chicago, IL 60637, USA
- Corey Beard
- ORCiD
- Department of Physics & Astronomy, University of California Irvine , Irvine, CA 92697, USA
- Madison Brady
- ORCiD
- Department of Astronomy & Astrophysics, University of Chicago , 5640 S. Ellis Avenue, Chicago, IL 60637, USA
- Max Brodheim
- ORCiD
- W. M. Keck Observatory , 65-1120 Mamalahoa Highway, Kamuela, HI 96743, USA
- Matt Brown
- W. M. Keck Observatory , 65-1120 Mamalahoa Highway, Kamuela, HI 96743, USA
- Ashley Chontos
- ORCiD
- Department of Astrophysical Sciences, Princeton University , 4 Ivy Lane, Princeton, NJ 08544, USA
- William Deich
- ORCiD
- UC Observatories, University of California , Santa Cruz, CA 95064, USA
- Jerry Edelstein
- ORCiD
- Space Sciences Laboratory, University of California , Berkeley, CA 94720, USA
- Benjamin J. Fulton
- ORCiD
- Department of Astronomy, California Institute of Technology , Pasadena, CA 91125, USA
- Steven Giacalone
- ORCiD
- Department of Astronomy, California Institute of Technology , Pasadena, CA 91125, USA
- Steven R. Gibson
- ORCiD
- Caltech Optical Observatories, California Institute of Technology , Pasadena, CA 91125, USA
- Gregory J. Gilbert
- ORCiD
- Department of Physics & Astronomy, University of California Los Angeles , Los Angeles, CA 90095, USA
- Samuel Halverson
- ORCiD
- Jet Propulsion Laboratory, California Institute of Technology , 4800 Oak Grove Drive, Pasadena, CA 91109, USA
- Luke Handley
- ORCiD
- Department of Astronomy, California Institute of Technology , Pasadena, CA 91125, USA; Department of Physics & Astronomy, University of California Los Angeles , Los Angeles, CA 90095, USA
- Grant M. Hill
- ORCiD
- W. M. Keck Observatory , 65-1120 Mamalahoa Highway, Kamuela, HI 96743, USA
- Rae Holcomb
- ORCiD
- Department of Physics & Astronomy, University of California Irvine , Irvine, CA 92697, USA
- Bradford Holden
- ORCiD
- UC Observatories, University of California , Santa Cruz, CA 95064, USA
- Aaron Householder
- ORCiD
- Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology , Cambridge, MA 02139, USA; Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology , Cambridge, MA 02139, USA
- Andrew W. Howard
- ORCiD
- Department of Astronomy, California Institute of Technology , Pasadena, CA 91125, USA
- Howard Isaacson
- ORCiD
- Department of Astronomy, 501 Campbell Hall, University of California , Berkeley, CA 94720, USA
- Stephen Kaye
- Caltech Optical Observatories, California Institute of Technology , Pasadena, CA 91125, USA
- Russ R. Laher
- ORCiD
- NASA Exoplanet Science Institute/Caltech-IPAC , MC 100-22, 1200 E. California Boulevard, Pasadena, CA 91125, USA
- Kyle Lanclos
- ORCiD
- W. M. Keck Observatory , 65-1120 Mamalahoa Highway, Kamuela, HI 96743, USA
- J. M. Joel Ong
- ORCiD
- Institute for Astronomy, University of Hawai‘i , 2680 Woodlawn Drive, Honolulu, HI 96822, USA ; [email protected]
- Joel Payne
- ORCiD
- W. M. Keck Observatory , 65-1120 Mamalahoa Highway, Kamuela, HI 96743, USA
- Erik A. Petigura
- ORCiD
- Department of Physics & Astronomy, University of California Los Angeles , Los Angeles, CA 90095, USA
- Daria Pidhorodetska
- ORCiD
- Department of Earth and Planetary Sciences, University of California , Riverside, CA 92521, USA
- Claire Poppett
- ORCiD
- Space Sciences Laboratory, University of California , Berkeley, CA 94720, USA
- Arpita Roy
- ORCiD
- Astrophysics & Space Institute , Schmidt Sciences, New York, NY 10011, USA
- Ryan Rubenzahl
- ORCiD
- Department of Astronomy, California Institute of Technology , Pasadena, CA 91125, USA
- Nicholas Saunders
- ORCiD
- Institute for Astronomy, University of Hawai‘i , 2680 Woodlawn Drive, Honolulu, HI 96822, USA ; [email protected]
- Christian Schwab
- ORCiD
- School of Mathematical and Physical Sciences, Macquarie University , Balaclava Road, North Ryde, NSW 2109, Australia
- Andreas Seifahrt
- ORCiD
- Department of Astronomy & Astrophysics, University of Chicago , 5640 S. Ellis Avenue, Chicago, IL 60637, USA
- Abby P. Shaum
- ORCiD
- Department of Astronomy, California Institute of Technology , Pasadena, CA 91125, USA
- Martin M. Sirk
- ORCiD
- Space Sciences Laboratory, University of California , Berkeley, CA 94720, USA
- Chris Smith
- Space Sciences Laboratory, University of California , Berkeley, CA 94720, USA
- Roger Smith
- ORCiD
- Caltech Optical Observatories, California Institute of Technology , Pasadena, CA 91125, USA
- Guđmundur Stefánsson
- ORCiD
- Anton Pannekoek Institute for Astronomy, University of Amsterdam , Science Park 904, 1098 XH Amsterdam, The Netherlands
- Julian Stürmer
- ORCiD
- Landessternwarte, Zentrum für Astronomie der Universität Heidelberg , Königstuhl 12, D-69117 Heidelberg, Germany
- Jim Thorne
- W. M. Keck Observatory , 65-1120 Mamalahoa Highway, Kamuela, HI 96743, USA
- Emma V. Turtelboom
- ORCiD
- Department of Astronomy, 501 Campbell Hall, University of California , Berkeley, CA 94720, USA
- Dakotah Tyler
- ORCiD
- Department of Physics and Astronomy, University of California , Los Angeles, CA 90095, USA
- John Valliant
- W. M. Keck Observatory , 65-1120 Mamalahoa Highway, Kamuela, HI 96743, USA
- Judah Van Zandt
- ORCiD
- Department of Physics & Astronomy, University of California Los Angeles , Los Angeles, CA 90095, USA
- Josh Walawender
- ORCiD
- W. M. Keck Observatory , 65-1120 Mamalahoa Highway, Kamuela, HI 96743, USA
- Samuel W. Yee
- ORCiD
- Center for Astrophysics ∣ Harvard & Smithsonian , 60 Garden Street, Cambridge, MA 02138, USA 29
- Sherry Yeh
- ORCiD
- W. M. Keck Observatory , 65-1120 Mamalahoa Highway, Kamuela, HI 96743, USA
- Jon Zink
- Department of Astronomy, California Institute of Technology , Pasadena, CA 91125, USA
- DOI
- https://doi.org/10.3847/1538-3881/ade677
- Journal volume & issue
-
Vol. 170,
no. 2
p. 109
Abstract
Hundreds of exoplanets between 1 and 1.8 times the size of Earth have been discovered on close-in orbits. However, these planets show such a diversity in densities that some appear to be made entirely of iron, while others appear to host gaseous envelopes. To test this diversity in composition, we update the masses of five rocky exoplanets (HD 93963 A b, Kepler-10 b, Kepler-100 b, Kepler-407 b, and TOI-1444 b) and present the confirmation of a new planet (TOI-1011) using 187 high-precision radial velocities from Gemini/MAROON-X and Keck/KPF. Our updated planet masses suggest compositions closer to that of Earth than previous literature values for all planets in our sample. In particular, we report that two previously identified “super-Mercuries” (Kepler-100 b and HD 93963 A b) have lower masses that suggest less iron-rich compositions. We then compare the ratio of iron to rock-building species with the abundance ratios of those elements in their host stars. These updated planet compositions do not suggest a steep relationship between planet and host star compositions, contradictory to previous results, and suggest that planets and host stars have similar abundance ratios.
Keywords
