Exploiting the Kepler transit data, we uncover a dramatic distinction in the prevalence of sub-Jovian companions, between systems that contain hot Jupiters (periods inward of 10 days) and those that host warm Jupiters (periods between 10 and 200 days). Hot Jupiters, with the singular exception of WASP-47b, do not have any detectable inner or outer planetary companions (with periods inward of 50 days and sizes down to 2R Earth ). Restricting ourselves to inner companions, our limits reach down to 1R Earth . In stark contrast, half of the warm Jupiters are closely flanked by small companions. Statistically, the companion fractions for hot and warm Jupiters are mutually exclusive, particularly in regard to inner companions.The high companion fraction of warm Jupiters also yields clues to their formation. The warm Jupiters that have close-by siblings should have low orbital eccentricities and low mutual inclinations. The orbital configurations of these systems are reminiscent of those of the low-mass, close-in planetary systems abundantly discovered by the Kepler mission. This, and other arguments, lead us to propose that these warm Jupiters are formed in-situ. There are indications that there may be a second population of warm Jupiters with different characteristics. In this picture, WASP-47b could be regarded as the extending tail of the in-situ warm Jupiters into the hot Jupiter region, and does not represent the generic formation route for hot Jupiters. Subject headings:1. FOREWORDS The origin of hot Jupiters (HJs, period inward of ∼ 10 days) has remained an unsolved issue. Although multiple scenarios have been proposed (disk migration, planet scattering, secular migration, etc.), none seem capable of satisfying all observational constraints. The recent discovery of two low-mass planetary companions (Becker et al. 2015) close to the hot Jupiter WASP-47b (Hellier et al. 2012) further obfuscates the picture. Motivated by the large population of low mass, closely-packed planets at small distances away from their host stars (Mayor et al. 2011;Howard et al. 2012;Borucki et al. 2011;Lissauer et al. 2011), and by the realization that some of them could have accumulated enough mass to undergo run-away gas accretion (Lee et al. 2014), Boley et al. (2016);Batygin et al. (2015) argue that WASP-47b, and possibly all hot Jupiters, were formed in-situ, instead of somehow transported inward. Only a tiny fraction of super-Earths need follow this path to be able to match the occurrence rate of hot Jupiters.While this seems a reasonable proposal for WASP-47b, could it explain the majority of hot Jupiters? To answer this, we focus on the following issue: is WASP-47b a generic hot Jupiter in terms of co-habiting with other planets? Currently, this question is best addressed by exploiting the Kepler data to look for small transiting bodies in systems hosting (either confirmed or candidate) There is a second goal to our paper: understanding the warm Jupiters (WJs). By this term we refer specifically to those giant planets orb...

We present 2241 exoplanet candidates identified with data from the Transiting Exoplanet Survey Satellite (TESS) during its 2 yr Prime Mission. We list these candidates in the TESS Objects of Interest (TOI) Catalog, which includes both new planet candidates found by TESS and previously known planets recovered by TESS observations. We describe the process used to identify TOIs, investigate the characteristics of the new planet candidates, and discuss some notable TESS planet discoveries. The TOI catalog includes an unprecedented number of small planet candidates around nearby bright stars, which are well suited for detailed follow-up observations. The TESS data products for the Prime Mission (sectors 1-26), including the TOI catalog, light curves, full-frame images, and target pixel files, are publicly available at the Mikulski Archive for Space Telescopes.

We determine the orbital eccentricities of individual small Kepler planets, through a combination of asteroseismology and transit light-curve analysis. We are able to constrain the eccentricities of 51 systems with a single transiting planet, which supplement our previous measurements of 66 planets in multi-planet systems. Through a Bayesian hierarchical analysis, we find evidence that systems with only one detected transiting planet have a different eccentricity distribution than systems with multiple detected transiting planets. The eccentricity distribution of the single-transiting systems is well described by the positive half of a zero-mean Gaussian distribution with a dispersion σ e = 0.32 ± 0.06, while the multiple-transit systems are consistent with σ e = 0.083 +0.015 −0.020 . A mixture model suggests a fraction of 0.76 +0.21 −0.12 of single-transiting systems have a moderate eccentricity, represented by a Rayleigh distribution that peaks at 0.26 +0.04 −0.06 . This finding may reflect differences in the formation pathways of systems with different numbers of transiting planets. We investigate the possibility that eccentricities are "self-excited" in closely packed planetary systems, as well as the influence of long-period giant companion planets. We find that both mechanisms can qualitatively explain the observations. We do not find any evidence for a correlation between eccentricity and stellar metallicity, as has been seen for giant planets. Neither do we find any evidence that orbital eccentricity is linked to the detection of a companion star. Along with this paper we make available all of the parameters and uncertainties in the eccentricity distributions, as well as the properties of individual systems, for use in future studies.Subject headings: planets and satellites: formation -planets and satellites: dynamical evolution and stability -planets and satellites: fundamental parameters -planets and satellites: terrestrial planets -stars: oscillations (including pulsations) -stars: planetary systems

We present a visible-light full orbital phase curve of the transiting planet WASP-18b measured by the TESS Mission. The phase curve includes the transit, secondary eclipse, and sinusoidal modulations across the orbital phase shaped by the planet's atmospheric characteristics and the star-planet gravitational interaction. We measure the beaming (Doppler boosting) and tidal ellipsoidal distortion phase modulations and show that the amplitudes of both agree with theoretical expectations. We find that the light from the planet's day-side hemisphere occulted during secondary eclipse, with a relative brightness of 341 +17 −18 ppm, is dominated by thermal emission, leading to an upper limit on the geometric albedo in the TESS band of 0.048 (2σ). We also detect the phase modulation due to the planet's atmosphere longitudinal brightness distribution. We find that its maximum is wellaligned with the sub-stellar point, to within 2.9 deg (2σ). We do not detect light from the planet's night-side hemisphere, with an upper limit of 43 ppm (2σ), which is 13% of the day-side brightness. The low albedo, lack of atmospheric phase shift, and inefficient heat distribution from the day to night hemispheres that we deduce from our analysis are consistent with theoretical expectations and similar findings for other strongly irradiated gas giant planets. This work demonstrates the potential of TESS data for studying full orbital phase curves of transiting systems. Finally, we complement our study by looking for transit timing variations (TTVs) in the TESS data and combined with previously published transit times, although we do not find a statistically significant TTV signal.