TESS Hunt for Young and Maturing Exoplanets (THYME). II. A 17 Myr Old Transiting Hot Jupiter in the Sco-Cen Association
Vanderburg, Andrew; Quinn, Samuel N.; Law, Nicholas M.; Zhou, George; Ziegler, Carl; Rizzuto, Aaron C.; Kraus, Adam L.; Mann, Andrew W.; Briceño, César; Newton, Elisabeth R.; Tofflemire, Benjamin M.; Wood, Mackenna L.; Thao, Pa Chia
United States, Sweden, Canada, Chile
Abstract
We present the discovery of a transiting hot Jupiter orbiting HIP 67522 (Teff ∼ 5650 K; M* ∼ 1.2M⊙) in the 10-20 Myr old Sco-Cen OB association. We identified the transits in the TESS data using our custom notch filter planet search pipeline and characterize the system with additional photometry from Spitzer; spectroscopy from SOAR/Goodman, SALT/HRS, LCOGT/NRES, and SMARTS/CHIRON; and speckle imaging from SOAR/HRCam. We model the photometry as a periodic Gaussian process with transits to account for stellar variability and find an orbital period of ${6.9596}_{-0.000015}^{+0.000016}$ days and radius of ${10.02}_{-0.53}^{+0.54}$ R⊕. We also identify a single transit of an additional candidate planet with radius ${8.01}_{-0.71}^{+0.75}$ R⊕ that has an orbital period of ≳23 days. The validated planet HIP 67522b is currently the youngest transiting hot Jupiter discovered and is an ideal candidate for transmission spectroscopy and radial velocity follow-up studies, while also demonstrating that some young giant planets either form in situ at small orbital radii or else migrate promptly from formation sites farther out in the disk.