0 Assigned ID: 544 ----- Attempting Submission 1 (Fri Apr 07 14:41:06 GMT 2017) ----- I changed the schedulability to 100% and trimmed exposures at the end of each orbit to allow 5 minutes of unused visibility time. 1321642011 ----- Attempting Submission 1 (Sat Jul 08 18:10:20 GMT 2017) ----- ----- Attempting Submission 2 (Wed Aug 30 21:15:00 GMT 2017) ----- ----- Attempting Submission 3 (Fri Oct 20 20:09:59 GMT 2017) ----- Thermal inversions have been one of the mostly hotly debated topics in exoplanet atmospheres over the last decade. Recent observations show conclusively that thermal inversions do exist for some of the most highly irradiated planets. The likeliest culprit for the inversions is strong absorption by titanium and vanadium oxide (TiO/VO) gas, which heats the upper atmosphere. However, TiO/VO have never been detected, despite many attempts. It is possible that these efforts failed because they focused on planets that were too cool, or were foiled by clouds and haze. We propose a novel search for TiO in the atmosphere of WASP-33b, a planet with a known thermal inversion (Haynes et al. 2015). We will measure the planet's thermal emission spectrum with the WFC3/G102 grism, where TiO is expected to have strong spectral features. This is the first proposed use of this grism for exoplanet emission spectroscopy. WASP-33b has the single highest signal-to-noise in thermal emission of any exoplanet known, and with one eclipse observation we will be sensitive to temperature differences in the upper atmosphere of <50 Kelvin. If TiO is present, we will detect it at high confidence (>10 sigma) and definitively settle the thermal inversion debate. We will obtain time series WFC3/G102 spectroscopy over five consecutive orbits coinciding with the secondary eclipse of WASP-33b. The observations must be scheduled to avoid the SAA crossing. We specify phase constraints such that orbits 3 and 4 occur during the eclipse event. Orbits 1, 2, and 5 will be used as baseline. Each orbit will begin with a direct image of the target star with the F139M filter for wavelength calibration. The remainder of each orbit will consist of 83 s exposures using the NSAMP = 9, SPARS10 readout pattern. To keep the fluence below saturation, we will use spatial scan mode with a 0.343 arcsec/sec scan rate (yielding a total scan height of 170 pixels). This setup will keep the maximum per pixel counts to below 30k electrons. We will alternate between forward and reverse scanning along the detector. We will also acquire one staring mode exposure at the beginning of orbit 1 to get a spatially separated spectrum of the nearby (~1") companion star (Moya et al. 2011). Planets and Planet Formation 6 false false false false false false SUPPORTED STAR EXTRA-SOLAR PLANETARY SYSTEM This object was generated by the targetselector and retrieved from the SIMBAD database. J2000 J2000 WFC3/IR Spectroscopic No No G102 1508530172253 /private/var/folders/ld/xnkt3v6n4_q75gg4bpm3zbs80000gn/T/OPVisit5109946977209844439.xml The scheduling data was generated by CASM 25.2. CASM was run in Phase II mode. (Tic-Visit :proposal-id 15109 :visit-id "01" :proposal-version -1 :trans-version "20170613" :date "20-Oct-2017 16:09:31.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 5 :saa-model "30" :si-bright-earth-limb-angle 20.0 :data-volume 2408672 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 15109 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 15109 :visit-id "01" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2325 :al-overhead-at-end 0 :internal-dur-at-end 0 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 2987 :pcs-gap 0 ) (Tic-Orbit :proposal-id 15109 :visit-id "01" :orbit-number 2 :pcs-time 222 :si-vis-utilization 2409 :al-overhead-at-end 0 :internal-dur-at-end 0 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 2987 :pcs-gap 0 ) (Tic-Orbit :proposal-id 15109 :visit-id "01" :orbit-number 3 :pcs-time 222 :si-vis-utilization 2409 :al-overhead-at-end 0 :internal-dur-at-end 0 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 2987 :pcs-gap 0 ) (Tic-Orbit :proposal-id 15109 :visit-id "01" :orbit-number 4 :pcs-time 222 :si-vis-utilization 2409 :al-overhead-at-end 0 :internal-dur-at-end 0 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 2987 :pcs-gap 0 ) (Tic-Orbit :proposal-id 15109 :visit-id "01" :orbit-number 5 :pcs-time 222 :si-vis-utilization 2409 :al-overhead-at-end 0 :internal-dur-at-end 682 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 2987 :pcs-gap 0 ) true 5 0