0 Assigned ID: 1116 ----- Attempting Submission 1 (Fri Apr 11 23:54:19 GMT 2014) ----- This target is not used in this proposal. This target is not used in this proposal. We look forward to working with you more closely during the implementation stage (several weeks around Jupiter opposition, 5 Feb. 2015). -1889226317 ----- Attempting Submission 1 (Mon Jul 14 21:06:17 GMT 2014) ----- Additional targets for offset acquisition are included for added scheduling flexibility. Io's active volcanos both directly establish local gas plumes and indirectly establish a more global sublimation atmosphere, through plume deposited sulfur dioxide frost patches. Despite decades of study and recent observational advances the very basic question about the relative role of each of these sources is unresolved. The correlation between volcanic activity variability and Io's dramatic influence on numerous time-variable phenomenon in the Jupiter system cannot be causally linked until this answer is in hand. Our experienced team has developed a novel approach to use STIS in a new way to obtain global radial profiles of SO2 scale height distributions above both plume and sublimation dominated regions. We exploit the bright Lyman-alpha dayglow of Jupiter as a background illumination source together with the strongly absorptive nature of SO2 at 121.6 nm to image Io's atmosphere in silhouette with unprecedented detail during transit events. Our program provides the following key information for SO2: 1) First high-altitude (>400 km) radial measurements of tangential column densities and scale heights; 2) First clear measurement of sublimation densities at polar locations; 3) Volcanic densities for large and mid-sized plumes (possibly new ones); 4) Globally distributed limb profiles allowing strong distinctions between plume and sublimation dominated locations; 5) Repeated imaging on a few day and a few week timescales for improved plume variability constraints; and 6) Lyman-alpha reflectance imaging at Io central lon. ~180 deg, filling a gap in previous coverage. These new information are critical to breaking through an impasse in our understanding of Io's atmosphere. Io transits Jupiter during each of 4 requested visits with one HST orbit each. The STIS G140M mode is used with the 52"x2" slit, which completely images the 1.16" disk of Io and its surrounding gas. Central wavelength 1222A selects the Lyman-alpha feature at 121.6 nm within its 119.4-124.9 nm range. The medium resolution mode dispersion is needed for spectral purity compared with STIS G140L, and diminishes potential confusion from nearby Jupiter continuum, Io aurora, and plasma torus features. Four visits with 1 orbit each are needed to search for plume density variability. To achieve the goal of constraining the timescales for variability in plume gas densities, two visits should be separated by a few days near Jupiter opposition and one additional visit each should be separated by ~3 weeks before and after opposition, respectively. The proximity to Jupiter opposition in Feb. 2015 both maximizes the spatial resolution and reduces the contribution of foreground geocoronal Lyman-alpha background signals, as the geometry is aligned with Earth shadow. Observations within a few weeks of opposition (February 5, 2015) hence maximize both the size of Io and the amount of time in Earth's shadow, reducing the background from terrestrial airglow emission from ~10-15 kR to instead ~2.5-4 kR. An essential requirement is to capture Io while in transit near Jupiter's central meridian. SOLAR SYSTEM 0 false true false false false AVAILABLE SOLAR SYSTEM Io is targeted while it transits the disc of Jupiter. An ideal program would further constrain one visit/orbit to occur when Io is located exactly in the center of the plasma torus, i.e. with sub-Jupiter system III latitude of 0 deg (i.e., CML=110 deg or 290 deg) and the other three visits to occur when Io is located at the extrema of the torus (i.e., CML=20 deg or 200 deg). Torus proton charge exchange induced auroral Lyman-alpha is expected to contribute a signal of 200-500 R in the same above limb region (Trafton, AJ, 2000). One orbit at low latitudes when the charge exchange rates are highest would test this process. The scheduling odds are good that this distribution would occur by happenstance, and so specific observing windows are not included for this 'nice-to-have' constraint. However, no more than two of the four visits should occur with Io at low magnetic latitudes, so that our primary SO2 attenuation measurement are not compromised. SATELLITE IO STD=JUPITER STD=IO TRANSIT OF IO ACROSS JUPITER FROM EARTH, SEP OF IO CALLISTO FROM EARTH GT 2", SEP OF IO EUROPA FROM EARTH GT 2", SEP OF IO GANYMEDE FROM EARTH GT 2", SIZE IO GT 1.0 EARTH SOLAR SYSTEM For target acquisition when Io is in Jupiter transit. SATELLITE EUROPA STD=JUPITER STD=EUROPA NOT TRANSIT OF EUROPA ACROSS JUPITER FROM EARTH, NOT ECL U OF EUROPA BY JUPITER, SEP OF EUROPA JUPITER FROM EARTH GT 2", SEP OF EUROPA CALLISTO FROM EARTH GT 2", SEP OF EUROPA GANYMEDE FROM EARTH GT 2" EARTH SOLAR SYSTEM For target acquisition when Io is in Jupiter transit. SATELLITE GANYMEDE STD=JUPITER STD=GANYMEDE SEP OF GANYMEDE JUPITER FROM EARTH GT 2", SEP OF GANYMEDE CALLISTO FROM EARTH GT 2", SEP OF GANYMEDE EUROPA FROM EARTH GT 2", NOT TRANSIT OF GANYMEDE ACROSS JUPITER FROM EARTH, NOT ECL U OF GANYMEDE BY JUPITER EARTH SOLAR SYSTEM For target acquisition when Io is in Jupiter transit. SATELLITE CALLISTO STD=JUPITER STD=CALLISTO SEP OF CALLISTO JUPITER FROM EARTH GT 2", SEP OF CALLISTO EUROPA FROM EARTH GT 2", SEP OF CALLISTO GANYMEDE FROM EARTH GT 2", NOT TRANSIT OF CALLISTO ACROSS JUPITER FROM EARTH, NOT ECL U OF CALLISTO BY JUPITER EARTH STIS/FUV-MAMA Spectroscopic No No G140M 1222 1419280522359 Using ephemeris for target 13805-01-EUROPA Using ephemeris for target 13805-01-IO The scheduling data was generated by CASM 22.2. CASM was run in Phase II mode. /private/var/folders/0c/5011wfl508g14lx4917hgxmr0006vr/T/OPVisit6191710156562390761.xml Highest accuracy guide-star tracking is desired. Consider minimizing BUFFER time down from 600 sec to reduce time lost between exposures. (Tic-Visit :proposal-id 13805 :visit-id "01" :proposal-version -1 :trans-version "20140605" :date "22-Dec-2014 15:35:21.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "24" :si-bright-earth-limb-angle 20.0 :data-volume 296224 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 13805 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Obset :proposal-id 13805 :visit-id "01" :obset-id "A1" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 13805 :visit-id "01" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2881 :al-overhead-at-end 0 :internal-dur-at-end 440 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3222 :pcs-gap 0 ) true 1 0 Satellite can be changed to Ganymede or Callisto (Target GANYMEDE-ACQ / CALLISTO-ACQ) if more suitable for acquisition. The CHECKBOX parameter needs to be changed to 27 (GANYMEDE) or 25 (CALLISTO). 1419280524202 Using ephemeris for target 13805-02-EUROPA Using ephemeris for target 13805-02-IO The scheduling data was generated by CASM 22.2. CASM was run in Phase II mode. /private/var/folders/0c/5011wfl508g14lx4917hgxmr0006vr/T/OPVisit7729366634707264457.xml Highest accuracy guide-star tracking is desired. Consider minimizing BUFFER time down from 600 sec to reduce time lost between exposures. (Tic-Visit :proposal-id 13805 :visit-id "02" :proposal-version -1 :trans-version "20140605" :date "22-Dec-2014 15:35:23.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "24" :si-bright-earth-limb-angle 20.0 :data-volume 296224 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 13805 :visit-id "02" :obset-id "02" :pcs-mode "FGS" ) (Tic-Obset :proposal-id 13805 :visit-id "02" :obset-id "A2" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 13805 :visit-id "02" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2881 :al-overhead-at-end 0 :internal-dur-at-end 440 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3222 :pcs-gap 0 ) true 1 0 Satellite can be changed to Ganymede or Callisto (Target GANYMEDE-ACQ / CALLISTO-ACQ) if more suitable for acquisition. The CHECKBOX parameter needs to be changed to 27 (GANYMEDE) or 25 (CALLISTO). 1419280525935 Using ephemeris for target 13805-03-EUROPA Using ephemeris for target 13805-03-IO The scheduling data was generated by CASM 22.2. CASM was run in Phase II mode. /private/var/folders/0c/5011wfl508g14lx4917hgxmr0006vr/T/OPVisit7359671108795948839.xml Highest accuracy guide-star tracking is desired. Consider minimizing BUFFER time down from 600 sec to reduce time lost between exposures. (Tic-Visit :proposal-id 13805 :visit-id "03" :proposal-version -1 :trans-version "20140605" :date "22-Dec-2014 15:35:25.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "24" :si-bright-earth-limb-angle 20.0 :data-volume 296224 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 13805 :visit-id "03" :obset-id "03" :pcs-mode "FGS" ) (Tic-Obset :proposal-id 13805 :visit-id "03" :obset-id "A3" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 13805 :visit-id "03" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2881 :al-overhead-at-end 0 :internal-dur-at-end 440 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3222 :pcs-gap 0 ) true 1 0 Satellite can be changed to Ganymede or Callisto (Target GANYMEDE-ACQ / CALLISTO-ACQ) if more suitable for acquisition. The CHECKBOX parameter needs to be changed to 27 (GANYMEDE) or 25 (CALLISTO). 1419280527508 Using ephemeris for target 13805-04-EUROPA Using ephemeris for target 13805-04-IO The scheduling data was generated by CASM 22.2. CASM was run in Phase II mode. /private/var/folders/0c/5011wfl508g14lx4917hgxmr0006vr/T/OPVisit3608416806087607326.xml Highest accuracy guide-star tracking is desired. Consider minimizing BUFFER time down from 600 sec to reduce time lost between exposures. (Tic-Visit :proposal-id 13805 :visit-id "04" :proposal-version -1 :trans-version "20140605" :date "22-Dec-2014 15:35:27.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "24" :si-bright-earth-limb-angle 20.0 :data-volume 296224 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 13805 :visit-id "04" :obset-id "04" :pcs-mode "FGS" ) (Tic-Obset :proposal-id 13805 :visit-id "04" :obset-id "A4" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 13805 :visit-id "04" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2881 :al-overhead-at-end 0 :internal-dur-at-end 440 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3222 :pcs-gap 0 ) true 1 0 Satellite can be changed to Ganymede or Callisto (Target GANYMEDE-ACQ / CALLISTO-ACQ) if more suitable for acquisition. The CHECKBOX parameter needs to be changed to 27 (GANYMEDE) or 25 (CALLISTO).