TESS Reveals HD 118203 b to be a Transiting Planet

Journal Article · Mon Jun 01 00:00:00 EDT 2020 · Astronomical Journal (New York, N.Y. Online)

DOI:https://doi.org/10.3847/1538-3881/AB84F2· OSTI ID:23013217

Pepper, Joshua ^[1]; Kane, Stephen R.; Mocnik, Teo; Dalba, Paul A. ^[2]; Rodriguez, Joseph E.; Eastman, Jason D. ^[3]; Hinkel, Natalie R. ^[4]; Daylan, Tansu; Crossfield, Ian; Ricker, George R. ^[5]; Gaudi, B. Scott ^[6]; Fetherolf, Tara ^[7]; Stassun, Keivan G. ^[8]; Campante, Tiago L.; Bossini, Diego ^[9]; Vanderburg, Andrew ^[10]; Huber, Daniel ^[11]; Howell, Steve B. ^[12]; Stephens, Andrew W. ^[13]; Furlan, E. ^[14] ; others, and

---

1. Department of Physics, Lehigh University, 16 Memorial Drive East, Bethlehem, PA 18015 (United States)
2. Department of Earth and Planetary Sciences, University of California, Riverside, CA 92521 (United States)
3. Center for Astrophysics, Harvard & Smithsonian, 60 Garden Street, Cambridge, MA 02138 (United States)
4. Southwest Research Institute, 6220 Culebra Road, San Antonio, TX 78238 (United States)
5. Department of Physics and Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States)
6. Department of Astronomy, The Ohio State University, 140 West 18th Avenue, Columbus, OH 43210 (United States)
7. Department of Physics and Astronomy, University of California, Riverside, CA 92521 (United States)
8. Vanderbilt University, Department of Physics & Astronomy, 6301 Stevenson Center Lane, Nashville, TN 37235 (United States)
9. Instituto de Astrofísica e Ciências do Espaço, Universidade do Porto, Rua das Estrelas, 4150-762 Porto (Portugal)
10. Department of Astronomy, The University of Texas at Austin, Austin, TX 78712 (United States)
11. Institute for Astronomy, University of Hawai‘i, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States)
12. NASA Ames Research Center, Moffett Field, CA 94035 (United States)
13. Gemini Observatory, NSF’s National Optical-Infrared Astronomy Research Laboratory, Hilo, HI 96720 (United States)
14. IPAC, Mail Code 314-6, Caltech, 1200 E. California Boulevard, Pasadena, CA 91125 (United States)

The exoplanet HD 118203 b, orbiting a bright (V = 8.05) host star, was discovered using the radial velocity method by da Silva et al., but was not previously known to transit. Transiting Exoplanet Survey Satellite (TESS) photometry has revealed that this planet transits its host star. Nine planetary transits were observed by TESS, allowing us to measure the radius of the planet to be 1.136{sub −0.028}{sup +0.029}R{sub J}, and to calculate the planet mass to be 2.166{sub −0.079}{sup +0.074}M{sub J}. The host star is slightly evolved with an effective temperature of T{sub eff}=5683{sub −85}{sup +84} K and a surface gravity of log g=3.889{sub 0.018}{sup 0.017}. With an orbital period of 6.134985{sub −0.000030}{sup +0.000029} days and an eccentricity of 0.314 ± 0.017, the planet occupies a transitional regime between circularized hot Jupiters and more dynamically active planets at longer orbital periods. The host star is among the 10 brightest known to have transiting giant planets, providing opportunities for both planetary atmospheric and asteroseismic studies.

• OSTI ID: 23013217
• Journal Information: Astronomical Journal (New York, N.Y. Online), Vol. 159, Issue 6; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 1538-3881
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
GRAVITATION
MASS
PHOTOMETRY
PLANETS
RADIAL VELOCITY
STARS