The exposures have been placed in non-int sequences, and the phase constraints have been widened for ease of scheduling. 149374245 ----- Attempting Submission 1 (Mon Mar 27 14:22:09 GMT 2017) ----- HST Phase II Proposal 14918 (w17_wfc3.apt) successfully submitted. Receipt: # 14918-1 ----- Attempting Submission 2 (Mon Mar 27 18:38:15 GMT 2017) ----- Definitive measurement of WASP-17b's water abundance in preparation for JWST In the advent of JWST, understanding of exoplanet atmospheres with current facilities will be critical. Here we propose to measure the transmission spectrum of WASP-17b in the near-infrared with both spectroscopic grisms of WFC3. Early HST and Spitzer surveys have shown WASP-17b to have the clearest atmosphere of any measured exoplanet so far, making it an important archetype hot Jupiter. As such, WASP-17b has been selected as a Hot-Jupiter archetype for detailed study through the JWST GTO program (PI Mountain/Clampin). Higher SNR observations, made possible through spatial scanning, of this key target in the HST WFC3 wavelength range will provide critical guidance and a point for comparison for the upcoming JWST observations. The existing WFC3 data was gathered before the revolutionary spacial scanning technique, and thus the observed H2O feature suffers from extremely large errors (factor of ~5X higher) even though WASP-17b remains the very best target for transmission spectroscopy. These observations combined with previous and future observations will allow us to accurately constrain the atmospheric water amplitude and abundance to high precision. Our HST observations will proide a transmission spectrum for the transiting exoplanet WASP-17b across the 0.8-1.7 micron wavelength range. WASP-17b is a highly inflated exoplanet, and is extremely amenable to atmospheric studies with HST and JWST. These observations with the G102 and G141 grisms in spatial scan mode will allow us to constrain the H2O abundance for this clear exoplanet atmosphere and better prepare us for the planned JWST GTO observations of this primed exoplanet target. For both WFC3 observations, we will use the forward spatial scanning mode using SPARS=25 and NSAMP=7. We will read out a subarray size of 256 pixels to reduce overheads. G102: we will use a scan rate of 0.0264 arcsec/sec, giving individual exposure times of 134 seconds, resulting in a scan across 3.5 arcsec = 27 pixels per exposure. This will leave plenty of room on the detector to estimate the background flux. G141: we will use a scan rate of 0.033 arcsec/sec, giving individual exposure times of 134 sec, resulting in a scan across 4.422 arcsec = 35 pixels per exposure. This will leave plenty of room on the detector to estimate the background flux. Planets and Planet Formation 0 false false false true false false SUPPORTED STAR EXTRA-SOLAR PLANET This object was generated by the targetselector and retrieved from the SIMBAD database. J2000 J2000 WFC3/IR Spectroscopic No No G102 WFC3/IR Spectroscopic No No G141 The scheduling data was generated by CASM 25.0. CASM was run in Phase II mode. WFC3 G141 IR transit of WASP-17. It is essential that the five orbits be scheduled in a coninuous block, preferably free of the SAA as the planet has a long transit. We will use the spatial scanning mode to lengthen the spectrum along the detector during the exposures, to avoid saturation on relatively long exposures. This mode also greatly increases the efficiency. (Tic-Visit :proposal-id 14918 :visit-id "01" :proposal-version -1 :trans-version "20170510" :date "06-Jun-2017 12:24:27.0" :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 681680 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 14918 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 14918 :visit-id "01" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2435 :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 3229 :pcs-gap 0 ) (Tic-Orbit :proposal-id 14918 :visit-id "01" :orbit-number 2 :pcs-time 222 :si-vis-utilization 2974 :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 3229 :pcs-gap 0 ) (Tic-Orbit :proposal-id 14918 :visit-id "01" :orbit-number 3 :pcs-time 222 :si-vis-utilization 2974 :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 3229 :pcs-gap 0 ) (Tic-Orbit :proposal-id 14918 :visit-id "01" :orbit-number 4 :pcs-time 222 :si-vis-utilization 2974 :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 3229 :pcs-gap 0 ) (Tic-Orbit :proposal-id 14918 :visit-id "01" :orbit-number 5 :pcs-time 222 :si-vis-utilization 2574 :al-overhead-at-end 0 :internal-dur-at-end 407 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3229 :pcs-gap 0 ) false 5 0 Direct image for wavelegnth calibration. Phase constrained so transit occurs between 2nd and 3rd contact. The scheduling data was generated by CASM 25.0. CASM was run in Phase II mode. WFC3 G102 IR transit of WASP-17. It is essential that the five orbits be scheduled in a coninuous block, preferably free of the SAA as the planet has a long transit. We will use the spatial scanning mode to lengthen the spectrum along the detector during the exposures, to avoid saturation on relatively long exposures. This mode also greatly increases the efficiency. 1497608289000 83.74693299525279 (Tic-Visit :proposal-id 14918 :visit-id "02" :proposal-version -1 :trans-version "20170510" :date "06-Jun-2017 12:23:54.0" :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 681680 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 14918 :visit-id "02" :obset-id "02" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 14918 :visit-id "02" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2424 :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 3229 :pcs-gap 0 ) (Tic-Orbit :proposal-id 14918 :visit-id "02" :orbit-number 2 :pcs-time 222 :si-vis-utilization 2960 :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 3229 :pcs-gap 0 ) (Tic-Orbit :proposal-id 14918 :visit-id "02" :orbit-number 3 :pcs-time 222 :si-vis-utilization 2960 :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 3229 :pcs-gap 0 ) (Tic-Orbit :proposal-id 14918 :visit-id "02" :orbit-number 4 :pcs-time 222 :si-vis-utilization 2960 :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 3229 :pcs-gap 0 ) (Tic-Orbit :proposal-id 14918 :visit-id "02" :orbit-number 5 :pcs-time 222 :si-vis-utilization 2562 :al-overhead-at-end 0 :internal-dur-at-end 407 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3229 :pcs-gap 0 ) false 5 0 The scheduling data was generated by CASM 25.2. CASM was run in Phase II mode. /private/var/folders/8k/sxlgy5ts2xdbykzf_vw6jrfw0001c5/T/OPVisit6358745069258537083.xml WFC3 G102 IR transit of WASP-17. It is essential that the five orbits be scheduled in a coninuous block, preferably free of the SAA as the planet has a long transit. We will use the spatial scanning mode to lengthen the spectrum along the detector during the exposures, to avoid saturation on relatively long exposures. This mode also greatly increases the efficiency. (Tic-Visit :proposal-id 14918 :visit-id "32" :proposal-version -1 :trans-version "20170613" :date "27-Jun-2017 12:59:13.0" :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 681680 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 14918 :visit-id "32" :obset-id "32" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 14918 :visit-id "32" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2424 :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 3225 :pcs-gap 0 ) (Tic-Orbit :proposal-id 14918 :visit-id "32" :orbit-number 2 :pcs-time 222 :si-vis-utilization 2960 :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 3225 :pcs-gap 0 ) (Tic-Orbit :proposal-id 14918 :visit-id "32" :orbit-number 3 :pcs-time 222 :si-vis-utilization 2960 :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 3225 :pcs-gap 0 ) (Tic-Orbit :proposal-id 14918 :visit-id "32" :orbit-number 4 :pcs-time 222 :si-vis-utilization 2960 :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 3225 :pcs-gap 0 ) (Tic-Orbit :proposal-id 14918 :visit-id "32" :orbit-number 5 :pcs-time 222 :si-vis-utilization 2562 :al-overhead-at-end 0 :internal-dur-at-end 407 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3225 :pcs-gap 0 ) true 5 0