The Astronomical Journal (Jan 2023)
Detecting Exomoons from Radial Velocity Measurements of Self-luminous Planets: Application to Observations of HR 7672 B and Future Prospects
- Jean-Baptiste Ruffio,
- Katelyn Horstman,
- Dimitri Mawet,
- Lee J. Rosenthal,
- Konstantin Batygin,
- Jason J. Wang,
- Maxwell Millar-Blanchaer,
- Ji Wang,
- Benjamin J. Fulton,
- Quinn M. Konopacky,
- Shubh Agrawal,
- Lea A. Hirsch,
- Andrew W. Howard,
- Sarah Blunt,
- Eric Nielsen,
- Ashley Baker,
- Randall Bartos,
- Charlotte Z. Bond,
- Benjamin Calvin,
- Sylvain Cetre,
- Jacques-Robert Delorme,
- Greg Doppmann,
- Daniel Echeverri,
- Luke Finnerty,
- Michael P. Fitzgerald,
- Nemanja Jovanovic,
- Ronald López,
- Emily C. Martin,
- Evan Morris,
- Jacklyn Pezzato,
- Garreth Ruane,
- Ben Sappey,
- Tobias Schofield,
- Andrew Skemer,
- Taylor Venenciano,
- J. Kent Wallace,
- Nicole L. Wallack,
- Peter Wizinowich,
- Jerry W. Xuan
Affiliations
- Jean-Baptiste Ruffio
- ORCiD
- Department of Astronomy, California Institute of Technology , Pasadena, CA 91125, USA ; [email protected]; Center for Astrophysics and Space Science, University of California, San Diego , La Jolla, CA 92093, USA
- Katelyn Horstman
- ORCiD
- Department of Astronomy, California Institute of Technology , Pasadena, CA 91125, USA ; [email protected]
- Dimitri Mawet
- ORCiD
- Department of Astronomy, California Institute of Technology , Pasadena, CA 91125, USA ; [email protected]; Jet Propulsion Laboratory, California Institute of Technology , 4800 Oak Grove Drive, Pasadena, CA 91109, USA
- Lee J. Rosenthal
- ORCiD
- Department of Astronomy, California Institute of Technology , Pasadena, CA 91125, USA ; [email protected]
- Konstantin Batygin
- ORCiD
- Division of Geological and Planetary Sciences, California Institute of Technology , Pasadena, CA 91125, USA
- Jason J. Wang
- ORCiD
- Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA) and Department of Physics and Astronomy, Northwestern University , Evanston, IL 60208, USA
- Maxwell Millar-Blanchaer
- ORCiD
- Department of Physics, University of California, Santa Barbara , Santa Barbara, CA 93106, USA
- Ji Wang
- ORCiD
- Department of Astronomy, The Ohio State University , 100 W 18th Avenue, Columbus, OH 43210, USA
- Benjamin J. Fulton
- ORCiD
- NASA Exoplanet Science Institute , Caltech/IPAC-NExScI, 1200 East California Boulevard, Pasadena, CA 91125, USA
- Quinn M. Konopacky
- ORCiD
- Center for Astrophysics and Space Science, University of California, San Diego , La Jolla, CA 92093, USA
- Shubh Agrawal
- ORCiD
- Department of Astronomy, California Institute of Technology , Pasadena, CA 91125, USA ; [email protected]; Department of Physics and Astronomy, University of Pennsylvania , Philadelphia, PA 19104, USA
- Lea A. Hirsch
- ORCiD
- Department of Chemical & Physical Sciences, University of Toronto Mississauga , 3359 Mississauga Road Mississauga, ON, L5L 1C6, Canada
- Andrew W. Howard
- ORCiD
- Department of Astronomy, California Institute of Technology , Pasadena, CA 91125, USA ; [email protected]
- Sarah Blunt
- ORCiD
- Department of Astronomy, California Institute of Technology , Pasadena, CA 91125, USA ; [email protected]
- Eric Nielsen
- ORCiD
- Department of Astronomy, New Mexico State University , P.O. Box 30001, USA
- Ashley Baker
- Department of Astronomy, California Institute of Technology , Pasadena, CA 91125, USA ; [email protected]
- Randall Bartos
- Jet Propulsion Laboratory, California Institute of Technology , 4800 Oak Grove Drive, Pasadena, CA 91109, USA
- Charlotte Z. Bond
- UK Astronomy Technology Centre , Royal Observatory, Edinburgh, EH9 3HJ, UK
- Benjamin Calvin
- Department of Astronomy, California Institute of Technology , Pasadena, CA 91125, USA ; [email protected]; Department of Physics & Astronomy, 430 Portola Plaza, University of California, Los Angeles , Los Angeles, CA 90095, USA
- Sylvain Cetre
- W. M. Keck Observatory , 65-1120 Mamalahoa Hwy, Kamuela, HI 96743, USA
- Jacques-Robert Delorme
- ORCiD
- Department of Astronomy, California Institute of Technology , Pasadena, CA 91125, USA ; [email protected]; W. M. Keck Observatory , 65-1120 Mamalahoa Hwy, Kamuela, HI 96743, USA
- Greg Doppmann
- W. M. Keck Observatory , 65-1120 Mamalahoa Hwy, Kamuela, HI 96743, USA
- Daniel Echeverri
- ORCiD
- Department of Astronomy, California Institute of Technology , Pasadena, CA 91125, USA ; [email protected]
- Luke Finnerty
- ORCiD
- Department of Physics & Astronomy, 430 Portola Plaza, University of California, Los Angeles , Los Angeles, CA 90095, USA
- Michael P. Fitzgerald
- ORCiD
- Department of Physics & Astronomy, 430 Portola Plaza, University of California, Los Angeles , Los Angeles, CA 90095, USA
- Nemanja Jovanovic
- ORCiD
- Department of Astronomy, California Institute of Technology , Pasadena, CA 91125, USA ; [email protected]
- Ronald López
- Department of Physics & Astronomy, 430 Portola Plaza, University of California, Los Angeles , Los Angeles, CA 90095, USA
- Emily C. Martin
- ORCiD
- Department of Astronomy & Astrophysics, University of California, Santa Cruz , Santa Cruz, CA 95064, USA
- Evan Morris
- Department of Astronomy & Astrophysics, University of California, Santa Cruz , Santa Cruz, CA 95064, USA
- Jacklyn Pezzato
- Department of Astronomy, California Institute of Technology , Pasadena, CA 91125, USA ; [email protected]
- Garreth Ruane
- ORCiD
- Department of Astronomy, California Institute of Technology , Pasadena, CA 91125, USA ; [email protected]; Jet Propulsion Laboratory, California Institute of Technology , 4800 Oak Grove Drive, Pasadena, CA 91109, USA
- Ben Sappey
- ORCiD
- Center for Astrophysics and Space Sciences, University of California, San Diego , La Jolla, CA 92093, USA
- Tobias Schofield
- Department of Astronomy, California Institute of Technology , Pasadena, CA 91125, USA ; [email protected]
- Andrew Skemer
- ORCiD
- Department of Astronomy & Astrophysics, University of California, Santa Cruz , Santa Cruz, CA 95064, USA
- Taylor Venenciano
- ORCiD
- Physics and Astronomy Department, Pomona College , 333 N. College Way, Claremont, CA 91711, USA
- J. Kent Wallace
- Jet Propulsion Laboratory, California Institute of Technology , 4800 Oak Grove Drive, Pasadena, CA 91109, USA
- Nicole L. Wallack
- ORCiD
- Earth and Planets Laboratory, Carnegie Institution for Science , Washington, DC 20015, USA
- Peter Wizinowich
- ORCiD
- W. M. Keck Observatory , 65-1120 Mamalahoa Hwy, Kamuela, HI 96743, USA
- Jerry W. Xuan
- ORCiD
- Department of Astronomy, California Institute of Technology , Pasadena, CA 91125, USA ; [email protected]
- DOI
- https://doi.org/10.3847/1538-3881/acb34a
- Journal volume & issue
-
Vol. 165,
no. 3
p. 113
Abstract
The detection of satellites around extrasolar planets, so called exomoons, remains a largely unexplored territory. In this work, we study the potential of detecting these elusive objects from radial velocity monitoring of self-luminous, directly imaged planets. This technique is now possible thanks to the development of dedicated instruments combining the power of high-resolution spectroscopy and high-contrast imaging. First, we demonstrate a sensitivity to satellites with a mass ratio of 1%–4% at separations similar to the Galilean moons from observations of a brown-dwarf companion (HR 7672 B; K _mag = 13; 0.″7 separation) with the Keck Planet Imager and Characterizer ( R ∼ 35,000 in the K band) at the W. M. Keck Observatory. Current instrumentation is therefore already sensitive to large unresolved satellites that could be forming from gravitational instability akin to binary star formation. Using end-to-end simulations, we then estimate that future instruments such as the Multi-Object Diffraction-limited High-resolution Infrared Spectrograph, planned for the Thirty Meter Telescope, should be sensitive to satellites with mass ratios of ∼10 ^−4 . Such small moons would likely form in a circumplanetary disk similar to the Jovian satellites in the solar system. Looking for the Rossiter–McLaughlin effect could also be an interesting pathway to detecting the smallest moons on short orbital periods. Future exomoon discoveries will allow precise mass measurements of the substellar companions that they orbit and provide key insight into the formation of exoplanets. They would also help constrain the population of habitable Earth-sized moons orbiting gas giants in the habitable zone of their stars.
Keywords
