----- Submission 1 (Thu Aug 18 17:13:22 GMT 2005) ----- The Exosphere of a Newly Discovered Transiting Planet We propose to use HST to directly detect the atmosphere and extended envelope (exosphere) of a recently discovered planet that transits the relatively bright star HD 149026. Absorption of background stellar Lyman-alpha emission is an extremely sensitive exospheric diagnostic that only HST can measure. If the HD 149026 planet is evaporating, then hydrogen in the exosphere should fill or overfill the Roche lobe, which has a size 4 times the diameter of Jupiter. If we do not detect a decrease in Lyman-alpha flux during several transits, then the hydrogen exosphere does not fill the Roche lobe of the planet and significant evaporation is unlikely. This would be a surprise, given that Vidal-Madjar et al. (2003) detected the exosphere of the planet that transits HD 209458, and the models of Lecavelier des Etangs et al. (2004) predict an order of magnitude more evaporation for the planet around HD 149026, due to its lower mass and smaller orbital distance. The newly discovered planet has 3 times the mean density and at least 3 times the core mass of the planet that transits HD 209458, which is consistent with significant exospheric evaporation in the past. We will also use ACS/PR200L observations to measure stellar limb darkening in the NUV, to detect Mg in the lower atmosphere of the planet, and to search for evidence of a moon or planetary rings.
This program consists of 4 visits. Visits 1 and 2 are identical, each requiring 5 orbits. These two visits alternate between using the ACS/SBC and the ACS/HRC, with the pattern SBC, HRC, SBC, HRC, SBC. Because visits 1 and 2 begin and end with the SBC, they require 5 consecutive SAA-free orbits. Visit 3 is similar to visits 1 and 2, except that it lacks the final SBC orbit. Because visit 3 uses the SBC in orbits 1 and 3, it requires 3 consecutive SAA-free orbits. The final HRC orbit of visit 3 may occur in an SAA-impacted orbit, though preferably with passage through the SAA occuring during occultation. Visit 4 is similar to visits 1 and 2, except that it lacks the initial SBC orbit. Because visit 4 uses the SBC in orbits 2 and 4, it requires 3 consecutive SAA-free orbits. The initial HRC orbit of visit 4 may occur in an SAA-impacted orbit, though preferably with passage through the SAA occuring during occultation. Each visit has the same period and zero phase constraint, giving the best current estimate of the HJD at the midpoint of the extrasolar planetary transit. The period and zero phase constraint may be refined once or twice during the life of this program. The phase constraint for each visit is on the ACS/SBC F125LP image at the beginning of orbit 3 (for visits 1, 2, and 3) or orbit 2 (for visit 4). The phase window is 96 minutes wide, allowing all possible phasings of the orbit of HST with the midpoint of the extrasolar planetary transit. To further improve schedulability, SCHED is set to 100%. Each orbit begins with a 60 second ACS/SBC F125LP image or a 1 second ACS/HRC F330W image. These manually inserted images take the place of autoimages. Cosmic ray splits are suppressed because the sequence of images can be used to identify cosmic rays or because the initial image is too short to be affected significantly by cosmic rays. The initial image in each orbit is followed by eight 265 second ACS/SBC PR110L images or twenty-two 56 second ACS/HRC PR200L images. Full-frame HRC exposures that are at least 56 seconds long can be dumped in parallel, avoiding the need for a serial dump after 16 exposures. Using the solar spectrum scaled to V=8.15, the ACS Imaging ETC predicts a global count rate of 5600 counts/sec and a peak local count rate of 3.4 counts/sec/pixel for the F125LP filter and the highest possible backgrounds [ACSIMAG50921]. Using coadded STIS spectra of HD 209458 scaled to V=8.15, the ACS Spectroscopic ETC predicts a global count rate of 20,000 counts/sec and a peak local count rate of 0.33 counts/sec/pixel, assuming a high geocoronal background [ACSSPEC48073]. The target (HD 149026) has no emission in the core of Ca II H & K (Sato et al. 2005), so the target is not active and not variable. According to the exposure time calculator, the ACS/HRC PR200L exposure will be 2x saturated at 2900 Angstroms and 200x saturated at 4500 Angstroms. The accurate photometry needed for this program relies on the fact that charge is not lost, even if it bleeds along CCD columns. GAIN=4 is used for all ACS/HRC exposures to completely sample the full well depth of CCD pixels. In addition, a POS TARG of 0.0, -1.25 arcsec is used for all ACS/HRC exposures. This POS TARG should place the red end of the prism spectrum near x=560 and y=460, which is a location on the HRC with a relatively deep full well capacity. SOLAR SYSTEM 12 false 0.0 false false false false false AVAILABLE STAR F3-F9 This object was generated by the targetselector and retrieved from the SIMBAD database. Parallax from HIP Catalog. Proper motions from Tycho-2 Catalog (-78.1 mas/yr = -0.00664 seconds of time/year). J2000 16 30 29.6192 +38 20 50.32 J2000 ACS/SBC Spectroscopic No No PR110L ACS/HRC Spectroscopic No No PR200L /data/norbert1/williamj/work/OP-cache/10718-v01.xml This visit requires 5 orbits (SBC, HRC, SBC, HRC, SBC). This visit requires 5 consecutive SAA-free orbits. Schedule visit 3 or 4 (which are different) instead, if only 3 consecutive SAA-free orbits are available. Visits 1 and 2 are identical. (Tic-Visit :proposal-id 10718 :visit-id "01" :proposal-version -1 :trans-version "20051113" :date "02-Feb-2006 14:00:08.0" :trans-errors '(:WARNINGS 1 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 5 :saa-model "27" :si-bright-earth-limb-angle 20.0 :data-volume 1346720 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 10718 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Obset :proposal-id 10718 :visit-id "01" :obset-id "A1" :pcs-mode "FGS" ) (Tic-Obset :proposal-id 10718 :visit-id "01" :obset-id "B1" :pcs-mode "FGS" ) (Tic-Obset :proposal-id 10718 :visit-id "01" :obset-id "C1" :pcs-mode "FGS" ) (Tic-Obset :proposal-id 10718 :visit-id "01" :obset-id "D1" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 10718 :visit-id "01" :orbit-number 1 :pcs-time 339 :si-vis-utilization 2632 :al-overhead-at-end 0 :internal-dur-at-end 480 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3029 :pcs-gap 0 ) (Tic-Orbit :proposal-id 10718 :visit-id "01" :orbit-number 2 :pcs-time 339 :si-vis-utilization 2645 :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 3029 :pcs-gap 0 ) (Tic-Orbit :proposal-id 10718 :visit-id "01" :orbit-number 3 :pcs-time 339 :si-vis-utilization 2659 :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 3029 :pcs-gap 0 ) (Tic-Orbit :proposal-id 10718 :visit-id "01" :orbit-number 4 :pcs-time 339 :si-vis-utilization 2618 :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 3029 :pcs-gap 0 ) (Tic-Orbit :proposal-id 10718 :visit-id "01" :orbit-number 5 :pcs-time 339 :si-vis-utilization 2632 :al-overhead-at-end 0 :internal-dur-at-end 655 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3029 :pcs-gap 0 ) false 5 1 /data/norbert1/williamj/work/OP-cache/10718-v01.xml qasi_states.start_state=WFHROPER end_state=WFHROBS. spec com transitions ACS from WFHROPER to WFMAHVON change qasi_states start and end states from WFMAHVON to WFHROBS change qasi_states start and end states from WFMAHVON to WFHROBS qasi_states.start_state=WFHROBS end_state=WFHROPER. spec com transitions ACS from WFMAHVON to WFHROPER qasi_states.start_state=WFHROPER end_state=WFHROBS. spec com transitions ACS from WFHROPER to WFMAHVON change qasi_states start and end states from WFMAHVON to WFHROBS change qasi_states start and end states from WFMAHVON to WFHROBS qasi_states.start_state=WFHROBS end_state=WFHROPER. spec com transitions ACS from WFMAHVON to WFHROPER qasi_states.start_state=WFHROPER end_state=WFHROBS. spec com transitions ACS from WFHROPER to WFMAHVON change qasi_states start and end states from WFMAHVON to WFHROBS change qasi_states start and end states from WFMAHVON to WFHROBS qasi_states.start_state=WFHROBS end_state=WFHROPER. spec com transitions ACS from WFMAHVON to WFHROPER /data/norbert1/williamj/work/OP-cache/10718-v02.xml This visit requires 5 orbits (SBC, HRC, SBC, HRC, SBC). This visit requires 5 consecutive SAA-free orbits. Schedule visit 3 or 4 (which are different) instead, if only 3 consecutive SAA-free orbits are available. Visits 1 and 2 are identical. (Tic-Visit :proposal-id 10718 :visit-id "02" :proposal-version -1 :trans-version "20051113" :date "02-Feb-2006 14:01:29.0" :trans-errors '(:WARNINGS 1 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 5 :saa-model "27" :si-bright-earth-limb-angle 20.0 :data-volume 1346720 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 10718 :visit-id "02" :obset-id "02" :pcs-mode "FGS" ) (Tic-Obset :proposal-id 10718 :visit-id "02" :obset-id "A2" :pcs-mode "FGS" ) (Tic-Obset :proposal-id 10718 :visit-id "02" :obset-id "B2" :pcs-mode "FGS" ) (Tic-Obset :proposal-id 10718 :visit-id "02" :obset-id "C2" :pcs-mode "FGS" ) (Tic-Obset :proposal-id 10718 :visit-id "02" :obset-id "D2" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 10718 :visit-id "02" :orbit-number 1 :pcs-time 339 :si-vis-utilization 2632 :al-overhead-at-end 0 :internal-dur-at-end 480 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3029 :pcs-gap 0 ) (Tic-Orbit :proposal-id 10718 :visit-id "02" :orbit-number 2 :pcs-time 339 :si-vis-utilization 2645 :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 3029 :pcs-gap 0 ) (Tic-Orbit :proposal-id 10718 :visit-id "02" :orbit-number 3 :pcs-time 339 :si-vis-utilization 2659 :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 3029 :pcs-gap 0 ) (Tic-Orbit :proposal-id 10718 :visit-id "02" :orbit-number 4 :pcs-time 339 :si-vis-utilization 2618 :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 3029 :pcs-gap 0 ) (Tic-Orbit :proposal-id 10718 :visit-id "02" :orbit-number 5 :pcs-time 339 :si-vis-utilization 2632 :al-overhead-at-end 0 :internal-dur-at-end 655 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3029 :pcs-gap 0 ) false 5 1 /data/norbert1/williamj/work/OP-cache/10718-v02.xml qasi_states.start_state=WFHROPER end_state=WFHROBS. spec com transitions ACS from WFHROPER to WFMAHVON change qasi_states start and end states from WFMAHVON to WFHROBS change qasi_states start and end states from WFMAHVON to WFHROBS qasi_states.start_state=WFHROBS end_state=WFHROPER. spec com transitions ACS from WFMAHVON to WFHROPER qasi_states.start_state=WFHROPER end_state=WFHROBS. spec com transitions ACS from WFHROPER to WFMAHVON change qasi_states start and end states from WFMAHVON to WFHROBS change qasi_states start and end states from WFMAHVON to WFHROBS qasi_states.start_state=WFHROBS end_state=WFHROPER. spec com transitions ACS from WFMAHVON to WFHROPER qasi_states.start_state=WFHROPER end_state=WFHROBS. spec com transitions ACS from WFHROPER to WFMAHVON change qasi_states start and end states from WFMAHVON to WFHROBS change qasi_states start and end states from WFMAHVON to WFHROBS qasi_states.start_state=WFHROBS end_state=WFHROPER. spec com transitions ACS from WFMAHVON to WFHROPER /data/norbert1/williamj/work/OP-cache/10718-v03.xml This visit requires 4 orbits (SBC, HRC, SBC, HRC). This visit requires 3 consecutive SAA-free orbits. Schedule visit 1 or 2 (which are identical) instead, if 5 consecutive SAA-free orbits are available. (Tic-Visit :proposal-id 10718 :visit-id "03" :proposal-version -1 :trans-version "20051113" :date "02-Feb-2006 14:02:15.0" :trans-errors '(:WARNINGS 1 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 4 :saa-model "27" :si-bright-earth-limb-angle 20.0 :data-volume 1180000 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 10718 :visit-id "03" :obset-id "03" :pcs-mode "FGS" ) (Tic-Obset :proposal-id 10718 :visit-id "03" :obset-id "A3" :pcs-mode "FGS" ) (Tic-Obset :proposal-id 10718 :visit-id "03" :obset-id "B3" :pcs-mode "FGS" ) (Tic-Obset :proposal-id 10718 :visit-id "03" :obset-id "C3" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 10718 :visit-id "03" :orbit-number 1 :pcs-time 339 :si-vis-utilization 2632 :al-overhead-at-end 0 :internal-dur-at-end 480 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3029 :pcs-gap 0 ) (Tic-Orbit :proposal-id 10718 :visit-id "03" :orbit-number 2 :pcs-time 339 :si-vis-utilization 2645 :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 3029 :pcs-gap 0 ) (Tic-Orbit :proposal-id 10718 :visit-id "03" :orbit-number 3 :pcs-time 339 :si-vis-utilization 2659 :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 3029 :pcs-gap 0 ) (Tic-Orbit :proposal-id 10718 :visit-id "03" :orbit-number 4 :pcs-time 339 :si-vis-utilization 2588 :al-overhead-at-end 0 :internal-dur-at-end 360 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3029 :pcs-gap 0 ) false 4 1 /data/norbert1/williamj/work/OP-cache/10718-v03.xml qasi_states.start_state=WFHROPER end_state=WFHROBS. spec com transitions ACS from WFHROPER to WFMAHVON change qasi_states start and end states from WFMAHVON to WFHROBS change qasi_states start and end states from WFMAHVON to WFHROBS qasi_states.start_state=WFHROBS end_state=WFHROPER. spec com transitions ACS from WFMAHVON to WFHROPER qasi_states.start_state=WFHROPER end_state=WFHROBS. spec com transitions ACS from WFHROPER to WFMAHVON change qasi_states start and end states from WFMAHVON to WFHROBS change qasi_states start and end states from WFMAHVON to WFHROBS qasi_states.start_state=WFHROBS end_state=WFHROPER. spec com transitions ACS from WFMAHVON to WFHROPER /data/norbert1/williamj/work/OP-cache/10718-v04.xml This visit requires 4 orbits (HRC, SBC, HRC, SBC). This visit requires 3 consecutive SAA-free orbits. Schedule visit 1 or 2 (which are identical) instead, if 5 consecutive SAA-free orbits are available. (Tic-Visit :proposal-id 10718 :visit-id "04" :proposal-version -1 :trans-version "20051113" :date "02-Feb-2006 14:02:56.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 4 :saa-model "27" :si-bright-earth-limb-angle 20.0 :data-volume 1180096 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 10718 :visit-id "04" :obset-id "04" :pcs-mode "FGS" ) (Tic-Obset :proposal-id 10718 :visit-id "04" :obset-id "A4" :pcs-mode "FGS" ) (Tic-Obset :proposal-id 10718 :visit-id "04" :obset-id "B4" :pcs-mode "FGS" ) (Tic-Obset :proposal-id 10718 :visit-id "04" :obset-id "C4" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 10718 :visit-id "04" :orbit-number 1 :pcs-time 339 :si-vis-utilization 2568 :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 3029 :pcs-gap 0 ) (Tic-Orbit :proposal-id 10718 :visit-id "04" :orbit-number 2 :pcs-time 339 :si-vis-utilization 2659 :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 3029 :pcs-gap 0 ) (Tic-Orbit :proposal-id 10718 :visit-id "04" :orbit-number 3 :pcs-time 339 :si-vis-utilization 2618 :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 3029 :pcs-gap 0 ) (Tic-Orbit :proposal-id 10718 :visit-id "04" :orbit-number 4 :pcs-time 339 :si-vis-utilization 2632 :al-overhead-at-end 0 :internal-dur-at-end 655 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3029 :pcs-gap 0 ) false 4 0 /data/norbert1/williamj/work/OP-cache/10718-v04.xml qasi_states.start_state=WFHROPER end_state=WFHROBS. spec com transitions ACS from WFHROPER to WFMAHVON change qasi_states start and end states from WFMAHVON to WFHROBS change qasi_states start and end states from WFMAHVON to WFHROBS qasi_states.start_state=WFHROBS end_state=WFHROPER. spec com transitions ACS from WFMAHVON to WFHROPER qasi_states.start_state=WFHROPER end_state=WFHROBS. spec com transitions ACS from WFHROPER to WFMAHVON change qasi_states start and end states from WFMAHVON to WFHROBS change qasi_states start and end states from WFMAHVON to WFHROBS qasi_states.start_state=WFHROBS end_state=WFHROPER. spec com transitions ACS from WFMAHVON to WFHROPER