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The Transiting Exoplanet Survey Satellite (TESS) provides a continuous suite of new planet candidates that need confirmation and precise mass determination from ground-based observatories. This is the case for the G-type star TOI-1710, which is known to host a transiting sub-Saturn planet ($\mathrm{M_p}=$28.3$\pm$4.7$\mathrm{M}_\oplus$) in a long-period orbit (P=24.28\,d). Here we combine archival SOPHIE and new and archival HARPS-N radial velocity data with newly available TESS data to refine the planetary parameters of the system and derive a new mass measurement for the transiting planet, taking into account the impact of the stellar activity on the mass measurement. We report for TOI-1710b a radius of $\mathrm{R_p}$$=$5.15$\pm$0.12$\mathrm{R}_\oplus$, a mass of $\mathrm{M_p}$$=$18.4$\pm$4.5$\mathrm{M}_\oplus$, and a mean bulk density of $\rho_{\rm p}$$=$0.73$\pm$0.18$\mathrm{g \, cm^{-3}}$, which are consistent at 1.2$\sigma$, 1.5$\sigma$, and 0.7$\sigma$, respectively, with previous measurements. Although there is not a significant difference in the final mass measurement, we needed to add a Gaussian process component to successfully fit the radial velocity dataset. This work illustrates that adding more measurements does not necessarily imply a better mass determination in terms of precision, even though they contribute to increasing our full understanding of the system. Furthermore, TOI-1710b joins an intriguing class of planets with radii in the range 4-8 $\mathrm{R}_\oplus$ that have no counterparts in the Solar System. A large gaseous envelope and a bright host star make TOI-1710b a very suitable candidate for follow-up atmospheric characterization., Comment: Accepted for publication in A&A. 21 pages, 14 figures

The next generation of wide-field deep astronomical surveys will deliver unprecedented amounts of images through the 2020s and beyond. As both the sensitivity and depth of observations increase, more blended sources will be detected. This reality can lead to measurement biases that contaminate key astronomical inferences. We implement new deep learning models available through Facebook AI Research's Detectron2 repository to perform the simultaneous tasks of object identification, deblending, and classification on large multi-band coadds from the Hyper Suprime-Cam (HSC). We use existing detection/deblending codes and classification methods to train a suite of deep neural networks, including state-of-the-art transformers. Once trained, we find that transformers outperform traditional convolutional neural networks and are more robust to different contrast scalings. Transformers are able to detect and deblend objects closely matching the ground truth, achieving a median bounding box Intersection over Union of 0.99. Using high quality class labels from the Hubble Space Telescope, we find that the best-performing networks can classify galaxies with near 100\% completeness and purity across the whole test sample and classify stars above 60\% completeness and 80\% purity out to HSC i-band magnitudes of 25 mag. This framework can be extended to other upcoming deep surveys such as the Legacy Survey of Space and Time and those with the Roman Space Telescope to enable fast source detection and measurement. Our code, \textsc{DeepDISC} is publicly available at \url{https://github.com/grantmerz/deepdisc}., Comment: 16 pages, 12 figures

TOI 1416 (BD+42 2504, HIP 70705) is a V=10 late G or early K-type dwarf star with transits detected by TESS. Radial velocities verify the presence of the transiting planet TOI-1416 b, with a period of 1.07d, a mass of $3.48 M_{Earth}$ and a radius of $1.62 R_{Earth}$, implying a slightly sub-Earth density of $4.50$ g cm$^{-3}$. The RV data also further indicate a tentative planet c with a period of 27.4 or 29.5 days, whose nature cannot be verified due to strong suspicions about contamination by a signal related to the Moon's synodic period of 29.53 days. The near-USP (Ultra Short Period) planet TOI-1416 b is a typical representative of a short-period and hot ($T_{eq} \approx$ 1570 K) super-Earth like planet. A planet model of an interior of molten magma containing a significant fraction of dissolved water provides a plausible explanation for its composition, and its atmosphere could be suitable for transmission spectroscopy with JWST. The position of TOI-1416 b within the radius-period distribution corroborates that USPs with periods of less than one day do not form any special group of planets. Rather, this implies that USPs belong to a continuous distribution of super-Earth like planets with periods ranging from the shortest known ones up to ~ 30 days, whose period-radius distribution is delimitated against larger radii by the Neptune desert and by the period-radius valley that separates super-Earths from sub-Neptune planets. In the abundance of small-short periodic planets against period, a plateau between periods of 0.6 to 1.4 days has however become notable that is compatible with the low-eccentricity formation channel. For the Neptune desert, its lower limits required a revision due to the increasing population of short period planets and new limits are provided. These limits are also given in terms of the planets' insolation and effective temperatures., Comment: 31 pages, 31 figures, 8 tables, accepted for publication in A&A

The TOI-1130 is a known planetary system around a K-dwarf consisting of a gas giant planet, TOI-1130 c, on an 8.4-day orbit, accompanied by an inner Neptune-sized planet, TOI-1130 b, with an orbital period of 4.1 days. We collected precise radial velocity (RV) measurements of TOI-1130 with the HARPS and PFS spectrographs as part of our ongoing RV follow-up program. We perform a photodynamical modeling of the HARPS and PFS RVs, and transit photometry from the Transiting Exoplanet Survey Satellite (TESS) and the TESS Follow-up Observing Program. We determine the planet masses and radii of TOI-1130 b and TOI-1130 c to be Mb = 19.28 $\pm$ 0.97 M$_\oplus$ and Rb = 3.56 $\pm$ 0.13 R$_\oplus$, and Mc = 325.59 $\pm$ 5.59 M$_\oplus$ and Rc = 13.32+1.55-1.41 R$_\oplus$, respectively. We spectroscopically confirm TOI-1130 b that was previously only validated. We find that the two planets orbit with small eccentricities in a 2:1 resonant configuration. This is the first known system with a hot Jupiter and an inner lower mass planet locked in a mean-motion resonance. TOI-1130 belongs to the small yet increasing population of hot Jupiters with an inner low-mass planet that challenges the pathway for hot Jupiter formation. We also detect a linear RV trend possibly due to the presence of an outer massive companion., Comment: 19 pages, Accepted to A&A

We report the discovery of TOI-1268b, a transiting Saturn-mass planet from the TESS space mission. With an age of less than one Gyr, derived from various age indicators, TOI-1268b is the youngest Saturn-mass planet known to date and contributes to the small sample of well characterised young planets. It has an orbital period of $P\,=\,8.1577080\pm0.0000044$ days, and transits an early K dwarf star with a mass of $M_\star$ = $ 0.96 \pm 0.04$ $M_{\odot}$, a radius of $R_\star$ = $ 0.92 \pm 0.06$ $R_{\odot}$, an effective temperature of $T_\mathrm{eff}\,=\,5300\pm100$ K, and a metallicity of $0.36\pm0.06$ dex. By combining TESS photometry with high-resolution spectra acquired with the Tull spectrograph at McDonald observatory, and the high-resolution spectrographs at Tautenburg and Ondrejov observatories, we measured a planetary mass of $M_\mathrm{p}\,=\,96.4 \pm 8.3\,M_{\oplus}$ and a radius of $R_\mathrm{p}\,=\,9.1 \pm 0.6\,R_{\oplus}$. TOI-1268 is an ideal system to study the role of star-planet tidal interactions for non-inflated Saturn-mass planets. We used system parameters derived in this paper to constrain the planet tidal quality factor to the range of $10^{4.5-5.3}$. When compared with the sample of other non-inflated Saturn-mass planets, TOI-1268b is one of the best candidates for transmission spectroscopy studies., Comment: 21 pages, 17 figures, accepted for publication in Astronomy & Astrophysics; see independent work by Dong et al. for Rossiter-McLaughlin measurement of TOI-1268b

We present a precise characterization of the TOI-561 planetary system obtained by combining previously published data with TESS and CHEOPS photometry, and a new set of $62$ HARPS-N radial velocities (RVs). Our joint analysis confirms the presence of four transiting planets, namely TOI-561 b ($P = 0.45$ d, $R = 1.42$ R$_\oplus$, $M = 2.0$ M$_\oplus$), c ($P = 10.78$ d, $R = 2.91$ R$_\oplus$, $M = 5.4$ M$_\oplus$), d ($P = 25.7$ d, $R = 2.82$ R$_\oplus$, $M = 13.2$ M$_\oplus$) and e ($P = 77$ d, $R = 2.55$ R$_\oplus$, $M = 12.6$ M$_\oplus$). Moreover, we identify an additional, long-period signal ($>450$ d) in the RVs, which could be due to either an external planetary companion or to stellar magnetic activity. The precise masses and radii obtained for the four planets allowed us to conduct interior structure and atmospheric escape modelling. TOI-561 b is confirmed to be the lowest density ($\rho_{\rm b} = 3.8 \pm 0.5$ g cm$^{-3}$) ultra-short period (USP) planet known to date, and the low metallicity of the host star makes it consistent with the general bulk density-stellar metallicity trend. According to our interior structure modelling, planet b has basically no gas envelope, and it could host a certain amount of water. In contrast, TOI-561 c, d, and e likely retained an H/He envelope, in addition to a possibly large water layer. The inferred planetary compositions suggest different atmospheric evolutionary paths, with planets b and c having experienced significant gas loss, and planets d and e showing an atmospheric content consistent with the original one. The uniqueness of the USP planet, the presence of the long-period planet TOI-561 e, and the complex architecture make this system an appealing target for follow-up studies., Comment: 22 pages, 19 figures. Accepted for publication in MNRAS

One of the main objectives of the Transiting Exoplanet Survey Satellite ({TESS}) mission is the discovery of small rocky planets around relatively bright nearby stars. Here, we report the discovery and characterization of the transiting super-Earth planet orbiting LHS~1478 (TOI-1640). The star is an inactive red dwarf ($J \sim 9.6$\,mag and spectral type m3\,V) with mass and radius estimates of $0.20\pm0.01$\,$M_{\odot}$ and $0.25\pm0.01$\,$R_{\odot}$, respectively, and an effective temperature of $3381\pm54$\,K.It was observed by \tess in four sectors. These data revealed a transit-like feature with a period of 1.949 days. We combined the TESS data with three ground-based transit measurements, 57 radial velocity (RV) measurements from CARMENES, and 13 RV measurements from IRD, determining that the signal is produced by a planet with a mass of $2.33^{+0.20}_{-0.20}$\,$M_{\oplus}$ and a radius of $1.24^{+0.05}_{-0.05}$\,$R_{\oplus}$. The resulting bulk density of this planet is 6.67\,g\,cm$^{-3}$, which is consistent with a rocky planet with an Fe- and MgSiO$_3$-dominated composition. Although the planet would be too hot to sustain liquid water on its surface (its equilibrium temperature is about $\sim$595\,K, suggesting a Venus-like atmosphere), spectroscopic metrics based on the capabilities of the forthcoming James Webb Space Telescope and the fact that the host star is rather inactive indicate that this is one of the most favorable known rocky exoplanets for atmospheric characterization., Comment: 14 pages, 10 figures, 6 tables, accepted for publication in A&A

We report the discovery of TOI 837b and its validation as a transiting planet. We characterize the system using data from the NASA TESS mission, the ESA Gaia mission, ground-based photometry from El Sauce and ASTEP400, and spectroscopy from CHIRON, FEROS, and Veloce. We find that TOI 837 is a $T=9.9$ mag G0/F9 dwarf in the southern open cluster IC 2602. The star and planet are therefore $35^{+11}_{-5}$ million years old. Combining the transit photometry with a prior on the stellar parameters derived from the cluster color-magnitude diagram, we find that the planet has an orbital period of $8.3\,{\rm d}$ and is slightly smaller than Jupiter ($R_{\rm p} = 0.77^{+0.09}_{-0.07} \,R_{\rm Jup}$). From radial velocity monitoring, we limit $M_{\rm p}\sin i$ to less than 1.20 $M_{\rm Jup}$ (3-$\sigma$). The transits either graze or nearly graze the stellar limb. Grazing transits are a cause for concern, as they are often indicative of astrophysical false positive scenarios. Our follow-up data show that such scenarios are unlikely. Our combined multi-color photometry, high-resolution imaging, and radial velocities rule out hierarchical eclipsing binary scenarios. Background eclipsing binary scenarios, though limited by speckle imaging, remain a 0.2% possibility. TOI 837b is therefore a validated adolescent exoplanet. The planetary nature of the system can be confirmed or refuted through observations of the stellar obliquity and the planetary mass. Such observations may also improve our understanding of how the physical and orbital properties of exoplanets change in time., Comment: AJ accepted. Figure 11 is my favorite. Comments welcome!

We report the detection of a transiting Earth-size planet around GJ 357, a nearby M2.5V star, using data from the Transiting Exoplanet Survey Satellite (TESS). GJ 357 b (TOI-562.01) is a transiting, hot, Earth-sized planet (Teq=525+-11 K) with a radius of Rb=1.217+-0.084 Re and an orbital period of Pb=3.93 d. Precise stellar radial velocities from CARMENES and PFS, as well as archival data from HIRES, UVES, and HARPS also display a 3.93-day periodicity, confirming the planetary nature and leading to a planetary mass of Mb=1.84+-0.31 Me. In addition to the radial velocity signal for GJ 357 b, more periodicities are present in the data indicating the presence of two further planets in the system: GJ 357 c, with a minimum mass of Mc=3.40+-0.46 Me in a 9.12 d orbit, and GJ 357 d, with a minimum mass of Md=6.1+-1.0 Me in a 55.7 d orbit inside the habitable zone. The host is relatively inactive and exhibits a photometric rotation period of Prot=78+-2 d. GJ 357 b is to date the second closest transiting planet to the Sun, making it a prime target for further investigations such as transmission spectroscopy. Therefore, GJ 357 b represents one of the best terrestrial planets suitable for atmospheric characterization with the upcoming JWST and ground-based ELTs.

We develop a comprehensive approach to simulate the deformation of mirrors and lenses due to thermal and mechanical stresses that couples efficiently to photon-based optics simulations. This expands upon previous work where we demonstrated a comprehensive ab initio approach to simulate astronomical images using a photon Monte Carlo method. We apply elasticity theory and estimate thermal effects by adapting a three-dimensional numerical method. We also consider the effect of active optics control systems and active cooling systems in further correcting distortions in the optics. We validate the approach by showing convergence to analytic estimates, and then apply the methodology to the WIYN 3.5m telescope primary mirror. We demonstrate that changes in the soak temperature result in second order point spread function (PSF) defocusing, the gravitational sag and positioning errors result in highly structured PSF distortions, and large-scale thermal gradients result in an elliptical PSF distortion patterns. All three aspects of the environment are larger than the intrinsic optical aberrations of the design, and further exploration with a variety of telescopes should lead to detailed PSF size and shape, astrometric distortion, and field variation predictions. The simulation capabilities developed in this work is publicly available with the Photon Simulation (PhoSim) package., Comment: Accepted for publication in ApJ; 14 pages, 19 figures

Only a few hot Jupiters are known to orbit around fast rotating stars. These exoplanets are harder to detect and characterize and may be less common than around slow rotators. Here, we report the discovery of the transiting hot Jupiter XO-6b, which orbits a bright, hot, and fast rotating star: V = 10.25, Teff = 6720 +/- 100 K, v sin i = 48 +/- 3 km/s. We detected the planet from its transits using the XO instruments and conducted a follow-up campaign. Because of the fast stellar rotation, radial velocities taken along the orbit do not yield the planet's mass with a high confidence level, but we secure a 3-sigma upper limit Mp < 4.4 MJup. We also obtain high resolution spectroscopic observations of the transit with the SOPHIE spectrograph at the 193-cm telescope of the Observatoire de Haute-Provence and analyze the stellar lines profile by Doppler tomography. The transit is clearly detected in the spectra. The radii measured independently from the tomographic analysis and from the photometric lightcurves are consistent, showing that the object detected by both methods is the same and indeed transits in front of XO-6. We find that XO-6b lies on a prograde and misaligned orbit with a sky-projected obliquity lambda = -20.7 +/- 2.3 deg. The rotation period of the star is shorter than the orbital period of the planet: Prot < 2.12 days, Porb = 3.77 days. Thus, this system stands in a largely unexplored regime of dynamical interactions between close-in giant planets and their host stars., Comment: 12 pages, 11 figures, Accepted for publication in AJ

The first discoveries of exoplanets around Sun-like stars have fueled efforts to find ever smaller worlds evocative of Earth and other terrestrial planets in the Solar System. While gas-giant planets appear to form preferentially around metal-rich stars, small planets (with radii less than four Earth radii) can form under a wide range of metallicities. This implies that small, including Earth-size, planets may have readily formed at earlier epochs in the Universe's history when metals were far less abundant. We report Kepler spacecraft observations of KOI-3158, a metal-poor Sun-like star from the old population of the Galactic thick disk, which hosts five planets with sizes between Mercury and Venus. We used asteroseismology to directly measure a precise age of 11.2+/-1.0 Gyr for the host star, indicating that KOI-3158 formed when the Universe was less than 20% of its current age and making it the oldest known system of terrestrial-size planets. We thus show that Earth-size planets have formed throughout most of the Universe's 13.8-billion-year history, providing scope for the existence of ancient life in the Galaxy., Comment: Submitted to EPJ Web of Conferences, to appear in the Proceedings of the 3rd CoRoT Symposium, Kepler KASC7 joint meeting; 4 pages, 1 figure

The chemical composition of stars hosting small exoplanets (with radii less than four Earth radii) appears to be more diverse than that of gas-giant hosts, which tend to be metal-rich. This implies that small, including Earth-size, planets may have readily formed at earlier epochs in the Universe's history when metals were more scarce. We report Kepler spacecraft observations of Kepler-444, a metal-poor Sun-like star from the old population of the Galactic thick disk and the host to a compact system of five transiting planets with sizes between those of Mercury and Venus. We validate this system as a true five-planet system orbiting the target star and provide a detailed characterization of its planetary and orbital parameters based on an analysis of the transit photometry. Kepler-444 is the densest star with detected solar-like oscillations. We use asteroseismology to directly measure a precise age of 11.2+/-1.0 Gyr for the host star, indicating that Kepler-444 formed when the Universe was less than 20% of its current age and making it the oldest known system of terrestrial-size planets. We thus show that Earth-size planets have formed throughout most of the Universe's 13.8-billion-year history, leaving open the possibility for the existence of ancient life in the Galaxy. The age of Kepler-444 not only suggests that thick-disk stars were among the hosts to the first Galactic planets, but may also help to pinpoint the beginning of the era of planet formation., Comment: Accepted for publication in ApJ; 42 pages, 10 figures, 4 tables

We present results of a long-baseline interferometry campaign using the PAVO beam combiner at the CHARA Array to measure the angular sizes of five main-sequence stars, one subgiant and four red giant stars for which solar-like oscillations have been detected by either Kepler or CoRoT. By combining interferometric angular diameters, Hipparcos parallaxes, asteroseismic densities, bolometric fluxes and high-resolution spectroscopy we derive a full set of near model-independent fundamental properties for the sample. We first use these properties to test asteroseismic scaling relations for the frequency of maximum power (nu_max) and the large frequency separation (Delta_nu). We find excellent agreement within the observational uncertainties, and empirically show that simple estimates of asteroseismic radii for main-sequence stars are accurate to <~4%. We furthermore find good agreement of our measured effective temperatures with spectroscopic and photometric estimates with mean deviations for stars between T_eff = 4600-6200 K of -22+/-32 K (with a scatter of 97K) and -58+/-31 K (with a scatter of 93 K), respectively. Finally we present a first comparison with evolutionary models, and find differences between observed and theoretical properties for the metal-rich main-sequence star HD173701. We conclude that the constraints presented in this study will have strong potential for testing stellar model physics, in particular when combined with detailed modelling of individual oscillation frequencies., Comment: 18 pages, 12 figures, 7 tables; accepted for publication in ApJ

We report for the first time a parametric fit to the pattern of the \ell = 1 mixed modes in red giants, which is a powerful tool to identify gravity-dominated mixed modes. With these modes, which share the characteristics of pressure and gravity modes, we are able to probe directly the helium core and the surrounding shell where hydrogen is burning. We propose two ways for describing the so-called mode bumping that affects the frequencies of the mixed modes. Firstly, a phenomenological approach is used to describe the main features of the mode bumping. Alternatively, a quasi-asymptotic mixed-mode relation provides a powerful link between seismic observations and the stellar interior structure. We used period \'echelle diagrams to emphasize the detection of the gravity-dominated mixed modes. The asymptotic relation for mixed modes is confirmed. It allows us to measure the gravity-mode period spacings in more than two hundred red giant stars. The identification of the gravity-dominated mixed modes allows us to complete the identification of all major peaks in a red giant oscillation spectrum, with significant consequences for the true identification of \ell = 3 modes, of \ell = 2 mixed modes, for the mode widths and amplitudes, and for the \ell = 1 rotational splittings. The accurate measurement of the gravity-mode period spacing provides an effective probe of the inner, g-mode cavity. The derived value of the coupling coefficient between the cavities is different for red giant branch and clump stars. This provides a probe of the hydrogen-shell burning region that surrounds the helium core. Core contraction as red giants ascend the red giant branch can be explored using the variation of the gravity-mode spacing as a function of the mean large separation., Comment: Accepted in A&A

The Kepler Data Characteristics Handbook (KDCH) provides a description of all phenomena identified in the Kepler data throughout the mission, and an explanation for how these characteristics are handled by the final version of the Kepler Data Processing Pipeline (SOC 9.3).The KDCH complements the Kepler Data Release Notes (KDRNs), which document phenomena and processing unique to a data release. The original motivation for this separation into static, explanatory text and a more journalistic set of figures and tables in the KDRN was for the user to become familiar with the Data Characteristics Handbook, then peruse the short Notes for a new quarter, referring back to the Handbook when necessary. With the completion of the Kepler mission and the final Data Release 25, both the KDCH and the DRN encompass the entire Kepler mission, so the distinction between them is in the level of exposition, not the extent of the time interval discussed.