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TOI-640 b is a hot, puffy Jupiter with a mass of $0.57 \pm 0.02$ M$_{\rm J}$ and radius of $1.72 \pm 0.05$ R$_{\rm J}$, orbiting a slightly evolved F-type star with a separation of $6.33^{+0.07}_{-0.06}$ R$_\star$. Through spectroscopic in-transit observations made with the HARPS spectrograph, we measured the Rossiter-McLaughlin effect, analysing both in-transit radial velocities and the distortion of the stellar spectral lines. From these observations, we find the host star to have a projected obliquity of $\lambda=184\pm3^\circ$. From the TESS light curve, we measured the stellar rotation period, allowing us to determine the stellar inclination, $i_\star=23^{+3\circ}_{-2}$, meaning we are viewing the star pole-on. Combining this with the orbital inclination allowed us to calculate the host star obliquity, $\psi=104\pm2^\circ$. TOI-640 b joins a group of planets orbiting over stellar poles within the range $80^\circ-125^\circ$. The origin of this orbital configuration is not well understood., Comment: 15 pages, 12 figures, accepted for publication in A&A, in press

Highly irradiated planets in the hot Neptune desert are usually either small (R < 2 Rearth) and rocky or they are gas giants with radii of >1 Rjup. Here, we report on the intermediate-sized planet TOI-2196 on a 1.2 day orbit around a G-type star discovered by TESS in sector 27. We collected 42 radial velocity measurements with the HARPS spectrograph to determine the mass. The radius of TOI-2196 b is 3.51 +/- 0.15 Rearth, which, combined with the mass of 26.0 +/- 1.3 Mearth, results in a bulk density of 3.31+0.51-0.43 g/cm3. Hence, the radius implies that this planet is a sub-Neptune, although the density is twice than that of Neptune. A significant trend in the HARPS radial velocities points to the presence of a distant companion with a lower limit on the period and mass of 220 days and 0.65 Mjup, respectively, assuming zero eccentricity. The short period of planet b implies a high equilibrium temperature of 1860 +/- 20 K, for zero albedo and isotropic emission. This places the planet in the hot Neptune desert, joining a group of very few planets in this parameter space discovered in recent years. These planets suggest that the hot Neptune desert may be divided in two parts for planets with equilibrium temperatures of > 1800 K: a hot sub-Neptune desert devoid of planets with radii of 1.8-3 Rearth and a sub-Jovian desert for radii of 5-12 Rearth. More planets in this parameter space are needed to further investigate this finding. Planetary interior structure models of TOI-2196 b are consistent with a H/He atmosphere mass fraction between 0.4 % and 3 %, with a mean value of 0.7 % on top of a rocky interior. We estimated the amount of mass this planet might have lost at a young age, and we find that while the mass loss could have been significant, the planet had not changed in terms of character: it was born as a small volatile-rich planet, and it remains one at present., 17 pages, 15 figures, 7 tables, accepted 11 July 2022 for publication in Astronomy & Astrophysics

TOI-640 b is a hot, puffy Jupiter with a mass of 0.57 ± 0.02 MJ and radius of 1.72 ± 0.05 RJ, orbiting a slightly evolved F-type star with a separation of 6.33−0.06+0.07 R⋆. Through spectroscopic in-transit observations made with the HARPS spectrograph, we measured the Rossiter-McLaughlin effect, analysing both in-transit radial velocities and the distortion of the stellar spectral lines. From these observations, we find the host star to have a projected obliquity of λ = 184 ± 3°. From the TESS light curve, we measured the stellar rotation period, allowing us to determine the stellar inclination, i⋆ = 23−2+3°, meaning we are viewing the star pole-on. Combining this with the orbital inclination allowed us to calculate the host star obliquity, ψ = 104 ± 2°. TOI-640 b joins a group of planets orbiting over stellar poles within the range 80°–125°. The origin of this orbital configuration is not well understood.

It is commonly accepted that exoplanets with orbital periods shorter than 1 day, also known as ultra-short period (USP) planets, formed further out within their natal protoplanetary disk, before migrating to their current-day orbits via dynamical interactions. One of the most accepted theories suggests a violent scenario involving high-eccentricity migration followed by tidal circularization. Here, we present the discovery of a four planet system orbiting the bright (V=10.5) K6 dwarf star TOI-500. The innermost planet is a transiting, Earth-sized USP planet with an orbital period of $\sim$ 13 hours, a mass of 1.42 $\pm$ 0.18 M$_{\oplus}$, a radius of $1.166^{0.061}_{-0.058}$ R$_{\oplus}$, and a mean density of 4.89$^{+1.03}_{-0.88}$ gcm$^{-3}$. Via Doppler spectroscopy, we discovered that the system hosts three outer planets on nearly circular orbits with periods of 6.6, 26.2, and 61.3d and minimum masses of 5.03 $\pm$ 0.41 M$_{\oplus}$, 33.12 $\pm$ 0.88 M$_{\oplus}$ and 15.05$^{+1.12}_{-1.11}$ M$_{\oplus}$, respectively. The presence of both a USP planet and a low-mass object on a 6.6-day orbit indicates that the architecture of this system can be explained via a scenario in which the planets started on low-eccentricity orbits, then moved inwards through a quasi-static secular migration. Our numerical simulations show that this migration channel can bring TOI-500 b to its current location in 2 Gyrs, starting from an initial orbit of 0.02au. TOI-500 is the first four planet system known to host a USP Earth analog whose current architecture can be explained via a non-violent migration scenario., Published on Nature Astronomy (April 28th, 2022)

Full list of authors: Tran, Quang H.; Bowler, Brendan P.; Endl, Michael; Cochran, William D.; MacQueen, Phillip J.; Gandolfi, Davide; Persson, Carina M.; Fridlund, Malcolm; Palle, Enric; Nowak, Grzegorz; Deeg, Hans J.; Luque, Rafael; Livingston, John H.; Kabáth, Petr; Skarka, Marek; Šubjak, Ján; Howell, Steve B.; Albrecht, Simon H.; Collins, Karen A.; Esposito, Massimiliano; Van Eylen, Vincent; Grziwa, Sascha; Goffo, Elisa; Huang, Chelsea X.; Jenkins, Jon M.; Karjalainen, Marie; Karjalainen, Raine; Knudstrup, Emil; Korth, Judith; Lam, Kristine W. F.; Latham, David W.; Levine, Alan M.; Osborne, H. L. M.; Quinn, Samuel N.; Redfield, Seth; Ricker, George R.; Seager, S.; Serrano, Luisa Maria; Smith, Alexis M. S.; Twicken, Joseph D.; Winn, Joshua N.--This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited., We report the discovery of two transiting planets around the bright (V = 9.9 mag) main-sequence F7 star TOI-1670 by the Transiting Exoplanet Survey Satellite. TOI-1670 b is a sub-Neptune (${R}_{{\rm{b}}}={2.06}_{-0.15}^{+0.19}$ R⊕) on a 10.9 day orbit, and TOI-1670 c is a warm Jupiter (${R}_{{\rm{c}}}={0.987}_{-0.025}^{+0.025}$ RJup) on a 40.7 day orbit. Using radial velocity observations gathered with the Tull Coudé Spectrograph on the Harlan J. Smith telescope and HARPS-N on the Telescopio Nazionale Galileo, we find a planet mass of ${M}_{{\rm{c}}}={0.63}_{-0.08}^{+0.09}$ MJup for the outer warm Jupiter, implying a mean density of ${\rho }_{c}={0.81}_{-0.11}^{+0.13}$ g cm−3. The inner sub-Neptune is undetected in our radial velocity data (Mb < 0.13 MJup at the 99% confidence level). Multiplanet systems like TOI-1670 hosting an outer warm Jupiter on a nearly circular orbit (${e}_{{\rm{c}}}={0.09}_{-0.04}^{+0.05}$) and one or more inner coplanar planets are more consistent with "gentle" formation mechanisms such as disk migration or in situ formation rather than high-eccentricity migration. Of the 11 known systems with a warm Jupiter and a smaller inner companion, eight (73%) are near a low-order mean-motion resonance, which can be a signature of migration. TOI-1670 joins two other systems (27% of this subsample) with period commensurabilities greater than 3, a common feature of in situ formation or halted inward migration. TOI-1670 and the handful of similar systems support a diversity of formation pathways for warm Jupiters. © 2022. The Author(s). Published by the American Astronomical Society., Q.H.T. and B.P.B. acknowledge support from a NASA FINESST grant (80NSSC20K1554). This work benefited from involvement in ExoExplorers, which is sponsored by the Exoplanets Program Analysis Group (ExoPAG) and NASA's Exoplanet Exploration Program Office (ExEP). B.P.B. acknowledges support from National Science Foundation grant AST-1909209 and NASA Exoplanet Research Program grant 20-XRP20_2-0119. C.M.P. and M.F. gratefully acknowledge the support of the Swedish National Space Agency (DNR 65/19 and 177/19). J.K. gratefully acknowledges the support of the Swedish National Space Agency (SNSA; DNR 2020-00104). P.K., M.S., J.S., and R.K. acknowledge the financial support of Inter-transfer grant No. LTT-20015. M.K. acknowledges support from ESAs PEA4000127913. M.E. acknowledges the support of the DFG priority program SPP 1992 "Exploring the Diversity of Extrasolar Planets" (HA 3279/12-1). Funding for the Stellar Astrophysics Centre is provided by the Danish National Research Foundation (grant agreement No. DNRF106). D.G. and L.M.S. gratefully acknowledge financial support from the Cassa di Risparmio di Torino (CRT) foundation under grant No. 2018.2323 "Gaseous or rocky? Unveiling the nature of small worlds." This work is partly supported by JSPS KAKENHI grant No. JP20K14518 and SATELLITE Research from Astrobiology Center (AB022006). Funding for the TESS mission is provided by NASA's Science Mission Directorate. This research has made use of the Exoplanet Follow-up Observation Program website, which is operated by the California Institute of Technology, under contract with the National Aeronautics and Space Administration under the Exoplanet Exploration Program. We acknowledge the use of public TESS data from pipelines at the TESS Science Office and the TESS Science Processing Operations Center. Resources supporting this work were provided by the NASA High-End Computing (HEC) Program through the NASA Advanced Supercomputing (NAS) Division at Ames Research Center for the production of the SPOC data products. This paper includes data collected by the TESS mission that are publicly available from the Mikulski Archive for Space Telescopes (MAST)., With funding from the Spanish government through the Severo Ochoa Centre of Excellence accreditation SEV-2017-0709.

Full list of authors: Hatzes, Artie P.; Gandolfi, Davide; Korth, Judith; Rodler, Florian; Sabotta, Silvia; Esposito, Massimiliano; Barragán, Oscar; Van Eylen, Vincent; Livingston, John H.; Serrano, Luisa Maria; Luque, Rafael; Smith, Alexis M. S.; Redfield, Seth; Persson, Carina M.; Pätzold, Martin; Palle, Enric; Nowak, Grzegorz; Osborne, Hannah L. M.; Narita, Norio; Mathur, Savita; Lam, Kristine W. F.; Kabáth, Petr; Johnson, Marshall C.; Guenther, Eike W.; Grziwa, Sascha; Goffo, Elisa; Fridlund, Malcolm; Endl, Michael; Deeg, Hans J.; Csizmadia, Szilard; Cochran, William D.; Cuesta, Lucía González; Chaturvedi, Priyanka; Carleo, Ilaria; Cabrera, Juan; Beck, Paul G.; Albrecht, Simon.--This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited., π Men hosts a transiting planet detected by the Transiting Exoplanet Survey Satellite space mission and an outer planet in a 5.7 yr orbit discovered by radial velocity (RV) surveys. We studied this system using new RV measurements taken with the HARPS spectrograph on ESO's 3.6 m telescope, as well as archival data. We constrain the stellar RV semiamplitude due to the transiting planet, π Men c, as Kc = 1.21 ± 0.12 m s−1, resulting in a planet mass of Mc = 3.63 ± 0.38 M⊕. A planet radius of Rc = 2.145 ± 0.015 R⊕ yields a bulk density of ρc = 2.03 ± 0.22 g cm−3. The precisely determined density of this planet and the brightness of the host star make π Men c an excellent laboratory for internal structure and atmospheric characterization studies. Our HARPS RV measurements also reveal compelling evidence for a third body, π Men d, with a minimum mass Md sin id = 13.38 ± 1.35 M⊕ orbiting with a period of Porb,d = 125 days on an eccentric orbit (ed = 0.22). A simple dynamical analysis indicates that the orbit of π Men d is stable on timescales of at least 20 Myr. Given the mutual inclination between the outer gaseous giant and the inner rocky planet and the presence of a third body at 125 days, π Men is an important planetary system for dynamical and formation studies. © 2022. The Author(s). Published by the American Astronomical Society., This work was supported by the KESPRINT collaboration, an international consortium devoted to the characterization and research of exoplanets discovered with space-based missions (www.kesprint.science). S.G., M.P., S.C., A.P.H., K.W.F.L., M.E., and H.R. acknowledge support by DFG grants PA525/18-1, PA525/19-1, PA525/20-1, HA 3279/12-1, and RA 714/14-1 within the DFG Schwerpunkt SPP 1992, "Exploring the Diversity of Extrasolar Planets." L.M.S. and D.G. gratefully acknowledge financial support from the CRT foundation under grant No. 2018.2323 "Gaseous or rocky? Unveiling the nature of small worlds." J.K. gratefully acknowledges the support of the Swedish National Space Agency (SNSA; DNR 2020-00104). P.G.B. acknowledges the financial support by NAWI Graz. We thank Matthias Hoeft and Alexander Drabent for use of the computer of the Tautenburg radio group for our dynamical study., With funding from the Spanish government through the Severo Ochoa Centre of Excellence accreditation SEV-2017-0709.

In order to understand the formation and evolution of small terrestrial planets not only their internal structure but also the architecture of their host system must be known. Systems harboring long-period cold gas and icy giants (a > 1 au) tend to host close-in small planets (a < 0.3 au, Rp < 4 R⊕) (Masuda et al. 2020). How does the presence of outer planets influence the formation and evolution of their inner smaller siblings? Unfortunately, our knowledge is still incomplete. Currently, the sample size for these systems is small and the relevant parameters are unknown. To truly understand the physics governing the formation and evolution of small planets we need to know the orbital architecture of their planetary systems. Here we present results from an ongoing radial velocity (RV) follow-up program conducted with the High Accuracy Radial velocity Planet Searcher (HARPS) spectrograph, mounted at the ESO 3.6m telescope of La Silla Observatory, and its twin for the Northern Hemisphere, the HARPS-N spectrograph, installed at the Telescopio Nazionale Galileo. Our program aims at measuring the mass of small transiting planets discovered by the TESS space telescope. The 4-year baseline of our project is allowing us to search for long-period outer planets, “expanding the horizon” and probing the architecture of planetary systems with inner small transiting planets., {"references":["Masuda et al. 2020"]}