WITHIN THE LAST TEN YEARS THE FIELD OF EXOPLANET ATMOSPHERIC CHARACTERIZATION HAS GROWN INTO A MATURE AND EXCITING FIELD. IN ADDITION TO THE MEASUREMENTS OF TRANSITING PLANETS THAT PROVIDE BASIC INFORMATION ABOUT ATMOSPHERIC COMPOSITION AND TEMPERATURE WE ARE ALSO ABLE TO DIRECTLY MEASURE PROPERTIES OF THE PLANET THAT ARE INHERENTLY THREE-DIMENSIONAL AND RELATED TO THE CIRCULATION PATTERN IN THE PLANET'S ATMOSPHERE. THESE INCLUDE MAPS OF THE PLANET'S BRIGHTNESS DISTRIBUTION AND RECENT MEASUREMENTS OF THE PLANETARY WIND SPEEDS THROUGH DOPPLER-SHIFTS IN HIGH-RESOLUTION SPECTRA. DUE TO THEIR FAVORABLE OBSERVABILITY ALL OF THESE MEASUREMENTS HAVE FIRST BEEN PERFORMED ON "HOT JUPITER" EXOPLANETS GAS GIANTS THAT ORBIT SEVERAL STELLAR RADII AWAY FROM THEIR HOST STARS. HOWEVER THESE OBSERVATIONAL TECHNIQUES ARE STARTING TO BE APPLIED TO SMALLER AND LONGER PERIOD PLANETS. THIS OBSERVATIONAL PURSUIT OF PLANETS BEYOND HOT JUPITERS WILL BE GREATLY ENHANCED ONCE THE TRANSITING EXOPLANET SURVEY SATELLITE (TESS) IS LAUNCHED AND IDENTIFIES MORE PLANETS AROUND BRIGHT STARS. THE EXPECTED PLANET YIELD FROM THIS MISSION INCLUDES PLANETS OUT TO ORBITAL PERIODS OF ~100 DAYS AND IT WILL DEFINITELY FIND MANY PLANETS WITH SMALLER RADII.HERE WE PROPOSE TO EXTEND OUR THEORETICAL MODELS OF HOT JUPITER ATMOSPHERIC CIRCULATION TO A MUCH WIDER DIVERSITY OF EXOPLANETS COMPLEMENTARY TO THE OBSERVATIONAL PROGRESS IN THIS FIELD. THE MAIN GOAL OF OUR PROPOSED RESEARCH IS TO CAREFULLY TEST FOR OBSERVATIONAL SIGNATURES THAT WILL ALLOW FUTURE MEASUREMENTS TO IDENTIFY TRANSITIONS BETWEEN THE DIFFERENT ATMOSPHERIC REGIMES THAT WE EXPECT THE NEWLY DISCOVERED PLANETS TO POPULATE. OUR THREE MAIN SCIENCE PROJECTS ARE: 1) EXPLORING THE ATMOSPHERIC DIVERSITY OF PLANETS ON LONGER PERIOD ORBITS WHERE THEIR ROTATION RATES WILL NO LONGER BE SET BY TIDAL SYNCHRONIZATION AND THEIR OBLIQUITIES MAY BE NON-ZERO 2) STUDYING THE RADIATIVE INFLUENCE OF AEROSOLS ON A PLANET'S ATMOSPHERIC CIRCULATION TO IDENTIFY MULTIPLE OBSERVABLE DIFFERENCES BETWEEN A CLEAR AND CLOUDY SKY 3) PUSHING DOWN TO SMALLER SIZED PLANETS AS THE PLANET-TYPE TRANSITIONS FROM MINI-NEPTUNE TO SUPER-EARTH SUCH THAT THE PRESENCE OF A SOLID SURFACE IMPACTS THE CIRCULATION PATTERNOUR EXISTING CODE IS WELL TESTED AND NATURALLY SUITED TO THIS WORK; WE WILL USE IT TO RUN A SUITE OF MODELS AND POST-PROCESS THE RESULTS FOR PREDICTIONS OF VARIOUS OBSERVABLES. WE WILL ALSO EXPAND THE CAPABILITIES OF OUR CIRCULATION CODE TO INCLUDE MORE PHYSICAL PROCESSES AND WILL EXTEND OUR POST-PROCESSING RADIATIVE TRANSFER CODE TO CALCULATE THE EMISSION PROPERTIES OF MODELED PLANETS.THIS PROPOSED WORK IS RELEVANT TO THE OBJECTIVES OF NASA'S ASTROPHYSICS THEORY PROGRAM IN THAT IT CONSISTS OF A COMBINATION OF THEORETICAL ASTROPHYSICS STUDIES AND THE DEVELOPMENT OF MODELS WITH DIRECT APPLICATION TO THE INTERPRETATION OF DATA FROM CURRENT SPACE ASTROPHYSICS MISSIONS (HUBBLE AND SPITZER) AND WILL RESULT IN PREDICTIONS THAT CAN BE TESTED WITH CURRENT AND FUTURE SPACE OBSERVATIONS (JWST). PARTICULARLY RELEVANT TO THE SUPPORT OF NASA MISSIONS WE WILL ALSO CONTRIBUTE TO THE SCIENCE RETURNS FROM TESS (AND THE K2 MISSION) BY HELPING TO PRIORITIZE WHICH TARGETS WILL MOST BENEFIT FROM FOLLOW-UP OBSERVATIONS THROUGH OUR PREDICTIONS OF OBSERVATIONAL SIGNATURES THAT CAN BE USED TO IDENTIFY ATMOSPHERIC REGIME TRANSITIONS.
$518,222FY2017National Aeronautics and Space AdministrationNASA
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