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Abstracts of Extreme Solar Systems 4 (Reykjavik, Iceland) American Astronomical Society August, 2019 100 — New Discoveries scope (JWST), as well as other large ground-based and space-based telescopes coming online in the next 100.01 — Review of TESS’s First Year Survey and two decades. Future Plans The status of the TESS mission as it completes its first year of survey operations in July 2019 will bere- George Ricker1 viewed. The opportunities enabled by TESS’s unique 1 Kavli Institute, MIT (Cambridge, Massachusetts, United States) lunar-resonant orbit for an extended mission lasting more than a decade will also be presented. Successfully launched in April 2018, NASA’s Tran- siting Exoplanet Survey Satellite (TESS) is well on its way to discovering thousands of exoplanets in orbit 100.02 — The Gemini Planet Imager Exoplanet Sur- around the brightest stars in the sky. During its ini- vey: Giant Planet and Brown Dwarf Demographics tial two-year survey mission, TESS will monitor more from 10-100 AU than 200,000 bright stars in the solar neighborhood at Eric Nielsen1; Robert De Rosa1; Bruce Macintosh1; a two minute cadence for drops in brightness caused Jason Wang2; Jean-Baptiste Ruffio1; Eugene Chiang3; by planetary transits. This first-ever spaceborne all- Mark Marley4; Didier Saumon5; Dmitry Savransky6; sky transit survey is identifying planets ranging in Daniel Fabrycky7; Quinn Konopacky8; Jennifer size from Earth-sized to gas giants, orbiting a wide Patience9; Vanessa Bailey10 variety of host stars, from cool M dwarfs to hot O/B 1 KIPAC, Stanford University (Stanford, California, United States) giants. 2 Jet Propulsion Laboratory, California Institute of Technology TESS stars are typically 30–100 times brighter than (Pasadena, California, United States) those surveyed by the Kepler satellite; thus, TESS 3 Astronomy, California Institute of Technology (Pasadena, Califor- planets are proving far easier to characterize with nia, United States) follow-up observations than those from prior mis- 4 Astronomy, U.C. Berkeley (Berkeley, California, United States) sions. Such TESS followup observations are enabling 5 NASA Ames Research Center (Mountain View, California, United measurements of the masses, sizes, densities, orbits, States) and atmospheres of a large cohort of small planets, 6 Los Alamos National Laboratory (Los Alamos, New Mexico, including a sample of habitable zone rocky worlds. United States) An additional data product from the TESS mission 7 Sibley School of Mechanical and Aerospace Engineering, Cornell is its full frame images (FFIs), which are collected at University (Ithaca, New York, United States) a cadence of 30 minutes. These FFIs provide precise 8 Astronomy & Astrophysics, University of Chicago (Chicago, photometric information for every object within the Illinois, United States) 2300 square degree instantaneous field of view of the 9 Center for Astrophysics and Space Science, U.C. San Diego (La TESS cameras. In total, nearly 100 million objects Jolla, California, United States) brighter than magnitude I = +16 will be precisely 10 SESE, Arizona State University (Tempe, Arizona, United States) photometered during the two-year prime mission. The initial TESS all-sky survey is well under- The Gemini Planet Imager Exoplanet Survey (GPIES) way, covering 13 observation sectors in the South- has observed 521 young, nearby stars, making it one ern Ecliptic Hemisphere during Year 1, and 13 obser- of the largest, deepest direct imaging surveys for gi- vation sectors in the Northern Ecliptic Hemisphere ant planets ever conducted. With detections of six during Year 2. A concurrent, year-long deep survey planets and four brown dwarfs, including the new by TESS of regions surrounding the North and South discoveries of 51 Eridani b and HR 2562 B, GPIES Ecliptic Poles will provide prime exoplanet targets also has a significantly higher planet detection rate for characterization with the James Webb Space Tele- than any published imaging survey. Our analysis 1 of the uniform sample of the first 300 stars reveals observations are typically performed using multi- new properties of giant planets (>2 MJup) from 3- object spectrographs on large telescopes, but previ- 100 AU. We find at >3 σ confidence that these plan- ous studies have been limited by the need to use blue ets are more common around high-mass stars (> 1.5 field stars to calibrate telluric variations, which have solar masses) than lower-mass stars. We also present provided a poor color match to the red target stars. evidence that giant planets and brown dwarfs obey Here, the companion stars provides an ideal telluric different mass functions and semi-major axis distri- calibrator, namely one of nearly equal brightness and butions. Our direct imaging data imply that the gi- similar spectral type located only 7 arcseconds from ant planet occurrence rate declines with semi-major the target. axis beyond 10 AU, a trend opposite to that found This work is supported by grants from the Na- by radial velocity surveys inside of 10 AU; taken to- tional Science Foundation and the John Templeton gether, the giant planet occurrence rate appears to Foundation. peak at 3-10 AU. All of these trends point to wide- separation giant planets forming by core/pebble ac- 100.04 — Evidence for an additional planet in the β cretion, and brown dwarfs forming by gravitational Pictoris system. instability. If our power-law model that fits giant 1 planets around high-mass stars is also applicable to Anne-Marie Lagrange 1 solar-type stars, and these power-laws remain valid Institut de Planétologie et d’Astrophysique de Grenoble (Saint down to the mass of Jupiter and inward to 5 AU, then Martin d’Heres, France) the occurrence rate for giant planets more massive than Jupiter within 100 AU could be less than 40%. With its well resolved debris disk of dust, its evapo- Looking beyond these results, we present our early rating exocomets, and an imaged giant planet orbit- analysis of the full GPIES sample, whether these ing at about 9 au, the young (∼23 Myr) β Pictoris sys- trends persist over all 521 observed stars, and impli- tem is a unique proxy for detailed studies of planet cations for future observations from Gemini-North formation and early evolution processes as well as with an upgraded GPI. planet-disk interactions. We have studied 10 years of ESO/HARPS high resolution spectroscopic data on the star. After removing the δ Scuti pulsations, a 100.03 — Three Red Suns in the Sky of the Nearest ∼1200 days periodic signal is observed. Within our Exoplanet Transiting an M Dwarf current knowledge, we can only attribute this signal David Charbonneau1; Jennifer Winters1; Amber to a second massive planet orbiting at ∼2.7 au from Medina1; Jonathan Irwin1 the star (Lagrange et al, 2019, Nat. Astron., under 1 Center for Astrophysics | Harvard & Smithsonian (Cambridge, minor revisions). To our knowledge, this is the first Massachusetts, United States) system hosting a planet detected in imaging and one detected with indirect technics. I will present the ev- The only terrestrial exoplanets whose atmospheres idence for this additional planet, and analyse the im- will be spectroscopically accessible in the near fu- pact of this result on previous results, including pre- ture will be those that orbit nearby mid-to-late M vious analysis of GAIA astrometric data, the system dwarfs. We present the discovery from TESS data dynamical stability, the exocomets activity. of LTT-1445Ab, a terrestrial planet transiting an M dwarf only 6.9 parsecs away, making it the closest 100.05 — Absence of a thick atmosphere on a ter- known transiting planet with a small-star primary. restrial exoplanet Remarkably, the host stellar system is composed of three mid-to-late M dwarfs in a hierarchical config- Laura Kreidberg1; Daniel D. B. Koll2; Caroline Morley3; uration, which are blended in a single TESS pixel. Renyu Hu9; Laura Schaefer4; Drake Deming5; Kevin We use follow-up observations from MEarth and the Stevenson6; Jason Dittmann2; Andrew Vanderburg3; centroid offset from the TESS data to determine that David Berardo2; Xueying Guo2; Keivan Stassun7; Ian the planet transits the primary star in the system. Crossfield2; David Charbonneau1; David Latham1; The planet has a radius 1.35 times that of Earth, an Abraham Loeb1; George Ricker8; Sara Seager2; Roland orbital period of 5.36 days, and an equilibrium tem- Vanderspek2 perature of 428 K, and the mass should be readily 1 Harvard University (Cambridge, Massachusetts, United States) measurable with radial velocity observations in the 2 MIT (Cambridge, Massachusetts, United States) coming months. The system is particularly favorable 3 UT Austin (Austin, Texas, United States) for ground-based observations to advance the study 4 Stanford University (Palo Alto, California, United States) of the atmospheres of terrestrial exoplanets: Such 5 University of Maryland (College Park, Maryland, United States) 2 6 Space Telescope Science Institute (Baltimore, Maryland, United 101 — Direct Imaging States) 7 Vanderbilt (Nashville, Tennessee, United States) 101.01 — Frequency of Massive Wide-orbit Plan- 8 Kavli Institute, MIT (Cambridge, Massachusetts, United States) ets vs. Stellar Mass: SPHERE SHINES on the ESO 9 Jet Propulsion Laboratory (Pasadena, California, United States) VLT 1 I will present a thermal phase curve measurement Michael Meyer 1 for a terrestrial exoplanet recently detected by the Department of Astronomy, The University of Michigan (Ann TESS mission. The planet is in a short period orbit Arbor, Michigan, United States) around a nearby M-dwarf star. The phase curve is the first such measurement for a planet smaller than We describe the SpHere INfrared Exoplanet (SHINE) 1.6 Earth radii, the size below which the existence of survey, a key part of the SPHERE GTO Program on an atmosphere is unknown a priori. The amplitude the ESO VLT, and present new statistical analyses of the phase variation puts strong constraints on the of the frequency of gas giant planet occurrence as planet’s atmospheric properties, which I will discuss.
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