Assigned ID: 179 ----- Attempting Submission 1 (Thu Feb 23 16:52:46 GMT 2012) ----- HST Phase I Proposal 179 (HST20_FP.pdf.apt) successfully submitted. ----- Attempting Submission 2 (Thu Feb 23 16:55:50 GMT 2012) ----- Set Wavecal=No (Availability=Available) for all STIS observations such that the duty cycle and photometric precision is maximized, as done in previous similar programs such as GO 11740, 12473 . ----- Attempting Submission 1 (Tue Jul 10 12:22:37 GMT 2012) ----- The hot Jupiters HD 189733b and HD 209458b are the cornerstones of our current understanding of exoplanetary atmospheres, having been well-observed across a broad range of wavelengths. Significant differences exist between them: the transmission spectrum of HD 209458b reveals a transparent atmosphere dominated by alkali metal lines, in stark contrast to the haze-covered atmosphere of HD 189733b. An exoplanetary atmosphere dominated by optical scattering, due to haze, is expected to possess a relatively high albedo. Measuring the albedo requires detecting the optical secondary eclipse, which has never been accomplished for HD 189733b. We propose to measure the planetary albedo of HD 189733b, thereby elucidating the importance of the observed haze on determining the energy budget of the exoplanet. We require HST STIS observations to not only detect the albedo, but also to measure how it varies with wavelength as expected from Rayleigh scattering. The first step towards detailed, comparative exoplanetology needs to be built upon a full comparison of the two best-studied exoplanets. Our proposed observations constitute a key part of the global picture of HD 189733b and will elucidate the importance of clouds and hazes on atmospheric chemistry and dynamics. One secondary transit of HD 189733 will be observed using STIS/G430L. The visit will consist of 4 HST orbits, with orbit 3 roughly centered on the planet transit, and orbits 2 and 4 outside of transit to establish the baseline. The first orbit is assumed not to be useful (instrument settling). Set Wavecal=No for all STIS observations (as in previous similar programs such as GO 11740, 12473) such that the duty cycle and photometric precision is maximized. With STIS G430L the wavelength range of 2900-5700 angstroms is covered. We use a broad 52x2" slit to minimize slit losses and variations. STIS is perfectly conserving past saturation with use of GAIN=4, see e.g. Bohlin and Gilliland 2004, AJ, 127, 3508 describing observations of the 0th mag star Vega. We adopt an exposure time of 66 seconds, with a sub-array size of 128 -- sufficiently large to enable tracking sky variations. This will lead to roughly 2x oversaturation. Photon-limited precisions of 0.00017 per resolution element, per HST orbit are expected. Set Wavecal=No (Availability=Available) for all STIS observations such that the duty cycle and photometric precision is maximized, as done in previous similar programs such as GO 11740, 12473 . EXTRA-SOLAR PLANETS 12 false 0.0 0.0 false false false false AVAILABLE STAR EXTRA-SOLAR PLANET K III-I This object was generated by the targetselector and retrieved from the SIMBAD database. J2000 J2000 STIS/CCD Spectroscopic No No G430L 4300 1341922841591 /private/var/folders/rj/rjwfS+BDGnOA8bpZkprK0U++0yk/-Tmp-/OPVisit276077433846102771.xml The scheduling data was generated by CASM 20.2. CASM was run in Phase II mode. It is essential that the four orbits be scheduled in a continuous block. (Tic-Visit :proposal-id 13006 :visit-id "01" :proposal-version -1 :trans-version "20120604" :date "10-Jul-2012 13:20:35.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 4 :saa-model "24" :si-bright-earth-limb-angle 20.0 :data-volume 330224 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 13006 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 13006 :visit-id "01" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2889 :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 3244 :pcs-gap 0 ) (Tic-Orbit :proposal-id 13006 :visit-id "01" :orbit-number 2 :pcs-time 222 :si-vis-utilization 3003 :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 3244 :pcs-gap 0 ) (Tic-Orbit :proposal-id 13006 :visit-id "01" :orbit-number 3 :pcs-time 222 :si-vis-utilization 3003 :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 3244 :pcs-gap 0 ) (Tic-Orbit :proposal-id 13006 :visit-id "01" :orbit-number 4 :pcs-time 222 :si-vis-utilization 3003 :al-overhead-at-end 123 :internal-dur-at-end 420 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3244 :pcs-gap 0 ) true 4 0 Short exposure to minimize instrument systematic of first exposure in each orbit. Short exposure to minimize instrument systematic of first exposure in each orbit. Short exposure to minimize instrument systematic of first exposure in each orbit. Explicit WAVECAL, auto-waves disabled