_version_ 1866918006873915392
author Hesse, Katharine
Mireles, Ismael
Bouchy, François
Dragomir, Diana
Ulmer-Moll, Solène
Eisner, Nora L.
Stassun, Keivan G.
Quinn, Samuel N.
Osborn, Hugh P.
Sousa, Sergio G.
Watkins, Cristilyn N.
Collins, Karen A.
Bryant, Edward M.
Irwin, Jonathan M.
Hellier, Coel
Johnson, Marshall C.
Ziegler, Carl
Howell, Steve B.
Anderson, David R.
Bayliss, Daniel
Bieryla, Allyson
Briceño, César
Butler, R. Paul
Charbonneau, David
Cloutier, Ryan
Crane, Jeffrey
Dittmann, Jason
Eastman, Jason D.
Freigeiro, Sebastián A.
Fulton, Benjamin J.
Gill, Samuel
Günther, Maximilian
Im, Haedam
Jenkins, Jon M.
Kunimoto, Michelle
Lavie, Baptiste
Lendl, Monika
Lund, Michael B.
Mann, Andrew W.
Nicholson, Belinda
Osip, David
Paegert, Martin
Santos, Nuno C.
Schwarz, Richard P.
Seager, Sara
Shectman, Stephen
Teske, Johanna
Twicken, Joseph D.
Udry, Stéphane
Van Eylen, Vincent
López, José Vinés
Wang, Sharon X.
Wheatley, Peter J.
Winn, Joshua N.
Zuidema, Edward E.
author_facet Hesse, Katharine
Mireles, Ismael
Bouchy, François
Dragomir, Diana
Ulmer-Moll, Solène
Eisner, Nora L.
Stassun, Keivan G.
Quinn, Samuel N.
Osborn, Hugh P.
Sousa, Sergio G.
Watkins, Cristilyn N.
Collins, Karen A.
Bryant, Edward M.
Irwin, Jonathan M.
Hellier, Coel
Johnson, Marshall C.
Ziegler, Carl
Howell, Steve B.
Anderson, David R.
Bayliss, Daniel
Bieryla, Allyson
Briceño, César
Butler, R. Paul
Charbonneau, David
Cloutier, Ryan
Crane, Jeffrey
Dittmann, Jason
Eastman, Jason D.
Freigeiro, Sebastián A.
Fulton, Benjamin J.
Gill, Samuel
Günther, Maximilian
Im, Haedam
Jenkins, Jon M.
Kunimoto, Michelle
Lavie, Baptiste
Lendl, Monika
Lund, Michael B.
Mann, Andrew W.
Nicholson, Belinda
Osip, David
Paegert, Martin
Santos, Nuno C.
Schwarz, Richard P.
Seager, Sara
Shectman, Stephen
Teske, Johanna
Twicken, Joseph D.
Udry, Stéphane
Van Eylen, Vincent
López, José Vinés
Wang, Sharon X.
Wheatley, Peter J.
Winn, Joshua N.
Zuidema, Edward E.
contents We report the discovery and confirmation of two planets orbiting the metal-poor Sun-like star, HD 35843 (TOI 4189). HD 35843 c is a temperate sub-Neptune transiting planet with an orbital period of 46.96 days that was first identified by Planet Hunters TESS. We combine data from TESS and follow-up observations to rule out false-positive scenarios and validate the planet. We then use ESPRESSO radial velocities to confirm the planetary nature and characterize the planet's mass and orbit. Further analysis of these RVs reveals the presence of an additional planet, HD 35843 b, with a period of 9.90 days and a minimum mass of $5.84\pm0.84$ $M_{\oplus}$. For HD 35843 c, a joint photometric and spectroscopic analysis yields a radius of $2.54 \pm 0.08 R_{\oplus}$, a mass of $11.32 \pm 1.60 M_{\oplus}$, and an orbital eccentricity of $e = 0.15\pm0.07$. With a bulk density of $3.80 \pm 0.70$ g/cm$^3$, the planet might be rocky with a substantial H$_2$ atmosphere or it might be a ``water world". With an equilibrium temperature of $\sim$480 K, HD 35843 c is among the coolest $\sim 5\%$ of planets discovered by TESS. Combined with the host star's relative brightness (V= 9.4), HD 35843 c is a promising target for atmospheric characterization that will probe this sparse population of temperate sub-Neptunes.
format Preprint
id arxiv_https___arxiv_org_abs_2505_00898
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle HD 35843: A Sun-like star hosting a long period sub-Neptune and inner super-Earth
Hesse, Katharine
Mireles, Ismael
Bouchy, François
Dragomir, Diana
Ulmer-Moll, Solène
Eisner, Nora L.
Stassun, Keivan G.
Quinn, Samuel N.
Osborn, Hugh P.
Sousa, Sergio G.
Watkins, Cristilyn N.
Collins, Karen A.
Bryant, Edward M.
Irwin, Jonathan M.
Hellier, Coel
Johnson, Marshall C.
Ziegler, Carl
Howell, Steve B.
Anderson, David R.
Bayliss, Daniel
Bieryla, Allyson
Briceño, César
Butler, R. Paul
Charbonneau, David
Cloutier, Ryan
Crane, Jeffrey
Dittmann, Jason
Eastman, Jason D.
Freigeiro, Sebastián A.
Fulton, Benjamin J.
Gill, Samuel
Günther, Maximilian
Im, Haedam
Jenkins, Jon M.
Kunimoto, Michelle
Lavie, Baptiste
Lendl, Monika
Lund, Michael B.
Mann, Andrew W.
Nicholson, Belinda
Osip, David
Paegert, Martin
Santos, Nuno C.
Schwarz, Richard P.
Seager, Sara
Shectman, Stephen
Teske, Johanna
Twicken, Joseph D.
Udry, Stéphane
Van Eylen, Vincent
López, José Vinés
Wang, Sharon X.
Wheatley, Peter J.
Winn, Joshua N.
Zuidema, Edward E.
Earth and Planetary Astrophysics
We report the discovery and confirmation of two planets orbiting the metal-poor Sun-like star, HD 35843 (TOI 4189). HD 35843 c is a temperate sub-Neptune transiting planet with an orbital period of 46.96 days that was first identified by Planet Hunters TESS. We combine data from TESS and follow-up observations to rule out false-positive scenarios and validate the planet. We then use ESPRESSO radial velocities to confirm the planetary nature and characterize the planet's mass and orbit. Further analysis of these RVs reveals the presence of an additional planet, HD 35843 b, with a period of 9.90 days and a minimum mass of $5.84\pm0.84$ $M_{\oplus}$. For HD 35843 c, a joint photometric and spectroscopic analysis yields a radius of $2.54 \pm 0.08 R_{\oplus}$, a mass of $11.32 \pm 1.60 M_{\oplus}$, and an orbital eccentricity of $e = 0.15\pm0.07$. With a bulk density of $3.80 \pm 0.70$ g/cm$^3$, the planet might be rocky with a substantial H$_2$ atmosphere or it might be a ``water world". With an equilibrium temperature of $\sim$480 K, HD 35843 c is among the coolest $\sim 5\%$ of planets discovered by TESS. Combined with the host star's relative brightness (V= 9.4), HD 35843 c is a promising target for atmospheric characterization that will probe this sparse population of temperate sub-Neptunes.
title HD 35843: A Sun-like star hosting a long period sub-Neptune and inner super-Earth
topic Earth and Planetary Astrophysics
url https://arxiv.org/abs/2505.00898