Wide-field surveys for transiting planets are well suited to searching diverse stellar populations, enabling a better understanding of the link between the properties of planets and their parent stars. We report the discovery of HAT-P-69 b (TOI 625.01) and HAT-P-70 b (TOI 624.01), two new hot Jupiters around A stars from the Hungarian-made Automated Telescope Network (HATNet) survey that have also been observed by the Transiting Exoplanet Survey Satellite. HAT-P-69 b has a mass of-+ 3.58 0.58 0.58 M Jup and a radius of-+ 1.676 0.033 0.051 R Jup and resides in a prograde 4.79 day orbit. HAT-P-70 b has a radius of-+ 1.87 0.10 0.15 R Jup and a mass constraint of s <6.78 3 ()M Jup and resides in a retrograde 2.74 day orbit. We use the confirmation of these planets around relatively massive stars as an opportunity to explore the occurrence rate of hot Jupiters as a function of stellar mass. We define a sample of 47,126 main-sequence stars brighter than T mag =10 that yields 31 giant planet candidates, including 18 confirmed planets, 3 candidates, and 10 false positives. We find a net hot Jupiter occurrence rate of 0.41±0.10% within this sample, consistent with the rate measured by Kepler for FGK stars. When divided into stellar mass bins, we find the occurrence rate to be 0.71±0.31% for G stars, 0.43±0.15% for F stars, and 0.26±0.11% for A stars. Thus, at this point, we cannot discern any statistically significant trend in the occurrence of hot Jupiters with stellar mass.

We present the new discovery of three new transiting hot-Jupiters by the WASP-South project, WASP-161 b, WASP-163 b and WASP-170 b. Follow-up radial velocities obtained with the Euler/CORALIE spectrograph and transit light-curves obtained with the TRAPPIST-North, TRAPPIST-South, SPECULOOS-South, NITES, and Euler telescopes have enabled us to determine the masses and radii for these transiting exoplanets. WASP-161 b completes an orbit around its V = 11.1 F6V-type host star in 5.406 days, and has a mass M p = 2.5 ± 0.2M Jup and radius R p = 1.14 ± 0.06 R Jup . WASP-163 b orbiting around its host star (spectral type G8V and the magnitude V = 12.5 ) each 1.609 days, and has a mass M P = 1.9 ± 0.2 M Jup and a radius R p = 1.2 ± 0.1 R Jup . WASP-170 b has a mass of 1.7 ± 0.2 M Jup and a radius of 1.14 ± 0.09 R Jup , is on a 2.344 days orbit around a G1V-type star of magnitude V = 12.8. Given their irradiations (∼ 10 9 erg.s −1 .cm −2 ) and masses, the three new planets' sizes are in the good agreement with classical models of irradiated giant planets.

We report on photometry and imaging of the Jupiter Family Comets 41P/Tuttle-Giacobini-Kresak and 45P/Honda-Mrkos-Pajdusakova with the TRAPPIST-North telescope. We observed 41P on 34 nights from February 16, 2017 to July 27, 2017 pre-and post-perihelion (r h =1.04 au), while we collected data for comet 45P from February 10 to March 30 after perihelion (r h =0.53 au). We computed the production rates of the daughter species OH, NH, CN, C 3 and C 2 and we measured the dust proxy, Afρ, for both comets. The peak of water production rate of 41P was (3.46±0.20)×10 27 molecules/s on April 3, 2017 when the comet was at 1.05 au from the Sun. We have shown that the activity of 41P is decreasing by about 30% to 40% from one apparition to the next. We measured a mean water production rate for 45P of (1.43±0.62)×10 27 molecules/s during a month after perihelion. Our results show that these Jupiter Family Comets had low gas and dust activity and no outburst was detected. Relative abundances, expressed as ratios of production rates and Afρ parameter with respect to OH and to CN, were compared to those measured in other comets. We found that 41P and 45P have a typical composition in term of carbon bearing species. The study of coma features exhibited by the CN gas species allowed the measurement of the rotation period of 41P, showing a surprisingly large increase of the rotation period from (30±5) hrs at the end of March to (50±10) hrs at the end of April, 2017 in agreement with recent observations by other teams.

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Context. The tenuous nitrogen (N2) atmosphere on Pluto undergoes strong seasonal effects due to high obliquity and orbital eccentricity, and has recently (July 2015) been observed by the New Horizons spacecraft. Aims. The main goals of this study are (i) to construct a well calibrated record of the seasonal evolution of surface pressure on Pluto and (ii) to constrain the structure of the lower atmosphere using a central flash observed in 2015. Methods. Eleven stellar occultations by Pluto observed between 2002 and 2016 are used to retrieve atmospheric profiles (density, pressure, temperature) between altitude levels of ~5 and ~380 km (i.e. pressures from ~ 10 μbar to 10 nbar). Results. (i) Pressure has suffered a monotonic increase from 1988 to 2016, that is compared to a seasonal volatile transport model, from which tight constraints on a combination of albedo and emissivity of N2 ice are derived. (ii) A central flash observed on 2015 June 29 is consistent with New Horizons REX profiles, provided that (a) large diurnal temperature variations (not expected by current models) occur over Sputnik Planitia; and/or (b) hazes with tangential optical depth of ~0.3 are present at 4–7 km altitude levels; and/or (c) the nominal REX density values are overestimated by an implausibly large factor of ~20%; and/or (d) higher terrains block part of the flash in the Charon facing hemisphere.