We propose a set of high SNR observations of the Pluto system that will provide improved lightcurves, orbits, and photometric properties of Nix and Hydra. The key photometric result for Nix and Hydra will be a vastly improved lightcurve shape and rotation period to test if the objects are in synchronous rotation or not. A second goal of this program will be to retrieve a new epoch of albedo map for the surface of Pluto. These observations will also improve masses and in some case densities for the bodies in the Pluto system.

This proposal contains a sequence of images of the Pluto system that is carefully timed to collect astrometry, photometry, and imaging data spaced out over a substantial fraction of a Pluto observing season. The observing cadence is set to optimally sample all of the perioidicities in the system (6.4-day, 38.4-day, and 51.2-day) over at least two periods for all variations while avoiding a systematic influence of solar phase angle. The provided cadence of the visits is strictly controlled in relative timing but the entire pattern can be shifted somewhat for schedulability. The observing pattern within each orbit is identical except for a small adjustment to the longest exposure time to ensure maximal usage of the target visibility window through the Cycle. The sequences of long, medium, and short exposures are required to retain astrometric and photometric information for this system given the wide range of target brightnesses (V=13.1 to 23.5). Each set of 4 like exposures use an optimize 4-point dithering pattern and the patterns for all exposures are themselves offset so that no fractional x or y position is repeated between an two exposures within a visit. The dithering pattern combines a small-offset pattern and a large-offset pattern intended to protect against systematic photometric and astrometric effects. All of the clear (F350LP) exposure sets are broken up within the orbit to provide for some temporal sampling within a visit. The F438W and F555W filter observations were not broken up because of the extra overhead that would have been incurred for the extra filter changes. The short clear exposures and the F555W data are largely to provide an accurate astrometric framework for the satellite astrometry. The F555W filter is the only one where the center-of-light to center-of-body offsets for Pluto are well enough calibrated to allow accurate placing of the system center-of-mass. These observations are required to bootstrap the reductions for the other filters. A 512 pixel sub-array was chosen to minimize the amount of data collected and thus avoid data dump overhead during the visibility window. The FOV of the sub-array is twice the size of the Pluto system and even with dithering and pointing uncertainties the system will fit on the image. SOLAR SYSTEM 12 false 0.0 0.0 false false false false false false SUPPORTED SOLAR SYSTEM Flux given is for Pluto at 1-degree phase angle, lightcurve mean, and at the opposition distance for 2010. For the same conditions Charon will be V=16.4, Nix will be V=23.3, and Hydra will be V=22.7. The pointing request assumes barycentric pointing but the field of view is large enough that Pluto body-center pointing would work just as well. PLANET Pluto System STD=PLUTO EARTH ACS/HRC Imaging No No CLEAR1S ACS/HRC Imaging No No F435W POS-TARG DITHER 0.145 LINE false false 2 46.84 WFC3-UVIS-DITHER-LINE 2 false Using ephemeris for target 11556-01-PLUTO-SYSTEM ephemeris data for target 11556-01-PLUTO-SYSTEM does not cover planning interval. Physical constraints are assumed to be unschedulable outside of the ephemeris data. Planning interval: 08.306 to 11.001. ephemeris interval: 09.151 to 11.152 Timing link suitability includes constraints ([02 After 01 by 26.9 to 27.4 days] [03 After 01 by 30.6 to 31.1 days] [04 After 01 by 38.6 to 39.1 days] [05 After 01 by 47.7 to 48.2 days] [06 After 01 by 61.5 to 62.0 days] [07 After 01 by 69.5 to 70.0 days] [08 After 01 by 72.7 to 73.2 days] [09 After 01 by 81.2 to 81.7 days] [10 After 01 by 91.3 to 91.8 days] [11 After 01 by 112.1 to 112.6 days] [12 After 01 by 134.9 to 135.4 days]) The scheduling data was generated by CASM 17.2. CASM was run in Phase II mode. The set of visits provided is a linked set of observations to provide a very specific observational cadence of the Pluto system. It is specially chosen to optimize the coverage of the system given the three major periods (Charon, Nix, and Hydra orbital periods). Visits 2-12 are linked to visit 1 rather than to each other so that the entire pattern is not destroyed by a compromise to any single visit. The scheduling window is provided at 12 hours long (+/- 6 hours from nominal) to make the program more easily schedulable. The actual length of this window may not be critical (though we'd rather not extend it much longer than this without considerable thought). Visit 6 has a special timing contraint, see comments there. The visits are sorted by time but are pseudo-random in sub-earth longitude on each body. (Tic-Visit :proposal-id 11556 :visit-id "01" :proposal-version -1 :trans-version "20091209" :date "29-Jan-2010 06:53:42.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "29" :si-bright-earth-limb-angle 20.0 :data-volume 91536 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 11556 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 11556 :visit-id "01" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2819 :al-overhead-at-end 0 :internal-dur-at-end 139 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3234 :pcs-gap 0 ) false 1 0 Using ephemeris for target 11556-02-PLUTO-SYSTEM ephemeris data for target 11556-02-PLUTO-SYSTEM does not cover planning interval. Physical constraints are assumed to be unschedulable outside of the ephemeris data. Planning interval: 08.306 to 11.001. ephemeris interval: 09.151 to 11.152 Timing link suitability includes constraints ([02 After 01 by 26.9 to 27.4 days]) The scheduling data was generated by CASM 17.2. CASM was run in Phase II mode. (Tic-Visit :proposal-id 11556 :visit-id "02" :proposal-version -1 :trans-version "20091209" :date "29-Jan-2010 06:56:17.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "29" :si-bright-earth-limb-angle 20.0 :data-volume 91536 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 11556 :visit-id "02" :obset-id "02" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 11556 :visit-id "02" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2819 :al-overhead-at-end 0 :internal-dur-at-end 139 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3234 :pcs-gap 0 ) false 1 0 Using ephemeris for target 11556-03-PLUTO-SYSTEM ephemeris data for target 11556-03-PLUTO-SYSTEM does not cover planning interval. Physical constraints are assumed to be unschedulable outside of the ephemeris data. Planning interval: 08.306 to 11.001. ephemeris interval: 09.151 to 11.152 Timing link suitability includes constraints ([03 After 01 by 30.6 to 31.1 days]) The scheduling data was generated by CASM 17.2. CASM was run in Phase II mode. (Tic-Visit :proposal-id 11556 :visit-id "03" :proposal-version -1 :trans-version "20091209" :date "29-Jan-2010 06:56:24.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "29" :si-bright-earth-limb-angle 20.0 :data-volume 91536 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 11556 :visit-id "03" :obset-id "03" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 11556 :visit-id "03" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2819 :al-overhead-at-end 0 :internal-dur-at-end 139 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3234 :pcs-gap 0 ) false 1 0 Using ephemeris for target 11556-04-PLUTO-SYSTEM ephemeris data for target 11556-04-PLUTO-SYSTEM does not cover planning interval. Physical constraints are assumed to be unschedulable outside of the ephemeris data. Planning interval: 08.306 to 11.001. ephemeris interval: 09.151 to 11.152 Timing link suitability includes constraints ([04 After 01 by 38.6 to 39.1 days]) The scheduling data was generated by CASM 17.2. CASM was run in Phase II mode. (Tic-Visit :proposal-id 11556 :visit-id "04" :proposal-version -1 :trans-version "20091209" :date "29-Jan-2010 06:56:30.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "29" :si-bright-earth-limb-angle 20.0 :data-volume 91536 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 11556 :visit-id "04" :obset-id "04" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 11556 :visit-id "04" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2819 :al-overhead-at-end 0 :internal-dur-at-end 139 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3234 :pcs-gap 0 ) false 1 0 Using ephemeris for target 11556-05-PLUTO-SYSTEM ephemeris data for target 11556-05-PLUTO-SYSTEM does not cover planning interval. Physical constraints are assumed to be unschedulable outside of the ephemeris data. Planning interval: 08.306 to 11.001. ephemeris interval: 09.151 to 11.152 Timing link suitability includes constraints ([05 After 01 by 47.7 to 48.2 days]) The scheduling data was generated by CASM 17.2. CASM was run in Phase II mode. (Tic-Visit :proposal-id 11556 :visit-id "05" :proposal-version -1 :trans-version "20091209" :date "29-Jan-2010 07:06:09.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "29" :si-bright-earth-limb-angle 20.0 :data-volume 91536 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 11556 :visit-id "05" :obset-id "05" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 11556 :visit-id "05" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2763 :al-overhead-at-end 0 :internal-dur-at-end 139 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3234 :pcs-gap 0 ) false 1 0 Using ephemeris for target 11556-06-PLUTO-SYSTEM ephemeris data for target 11556-06-PLUTO-SYSTEM does not cover planning interval. Physical constraints are assumed to be unschedulable outside of the ephemeris data. Planning interval: 08.306 to 11.001. ephemeris interval: 09.151 to 11.152 Timing link suitability includes constraints ([06 After 01 by 61.5 to 62.0 days]) The scheduling data was generated by CASM 17.2. CASM was run in Phase II mode. The timing constraint on this visit is provided to ensure that either Visit 6 or visit 7 falls within 12 hours of minimum phase angle in the 2010 apparition of Pluto. Doing so returns the optimal phase angle coverage pattern from our observational sequence. (Tic-Visit :proposal-id 11556 :visit-id "06" :proposal-version -1 :trans-version "20091209" :date "29-Jan-2010 07:06:16.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "29" :si-bright-earth-limb-angle 20.0 :data-volume 91536 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 11556 :visit-id "06" :obset-id "06" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 11556 :visit-id "06" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2751 :al-overhead-at-end 0 :internal-dur-at-end 139 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3234 :pcs-gap 0 ) false 1 0 Using ephemeris for target 11556-07-PLUTO-SYSTEM ephemeris data for target 11556-07-PLUTO-SYSTEM does not cover planning interval. Physical constraints are assumed to be unschedulable outside of the ephemeris data. Planning interval: 08.306 to 11.001. ephemeris interval: 09.151 to 11.152 Timing link suitability includes constraints ([07 After 01 by 69.5 to 70.0 days]) The scheduling data was generated by CASM 17.2. CASM was run in Phase II mode. (Tic-Visit :proposal-id 11556 :visit-id "07" :proposal-version -1 :trans-version "20091209" :date "29-Jan-2010 07:06:22.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "29" :si-bright-earth-limb-angle 20.0 :data-volume 91536 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 11556 :visit-id "07" :obset-id "07" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 11556 :visit-id "07" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2779 :al-overhead-at-end 0 :internal-dur-at-end 139 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3234 :pcs-gap 0 ) false 1 0 Using ephemeris for target 11556-08-PLUTO-SYSTEM ephemeris data for target 11556-08-PLUTO-SYSTEM does not cover planning interval. Physical constraints are assumed to be unschedulable outside of the ephemeris data. Planning interval: 08.306 to 11.001. ephemeris interval: 09.151 to 11.152 Timing link suitability includes constraints ([08 After 01 by 72.7 to 73.2 days]) The scheduling data was generated by CASM 17.2. CASM was run in Phase II mode. (Tic-Visit :proposal-id 11556 :visit-id "08" :proposal-version -1 :trans-version "20091209" :date "29-Jan-2010 07:06:28.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "29" :si-bright-earth-limb-angle 20.0 :data-volume 91536 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 11556 :visit-id "08" :obset-id "08" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 11556 :visit-id "08" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2791 :al-overhead-at-end 0 :internal-dur-at-end 139 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3234 :pcs-gap 0 ) false 1 0 Using ephemeris for target 11556-09-PLUTO-SYSTEM ephemeris data for target 11556-09-PLUTO-SYSTEM does not cover planning interval. Physical constraints are assumed to be unschedulable outside of the ephemeris data. Planning interval: 08.306 to 11.001. ephemeris interval: 09.151 to 11.152 Timing link suitability includes constraints ([09 After 01 by 81.2 to 81.7 days]) The scheduling data was generated by CASM 17.2. CASM was run in Phase II mode. (Tic-Visit :proposal-id 11556 :visit-id "09" :proposal-version -1 :trans-version "20091209" :date "29-Jan-2010 07:06:35.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "29" :si-bright-earth-limb-angle 20.0 :data-volume 91536 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 11556 :visit-id "09" :obset-id "09" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 11556 :visit-id "09" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2819 :al-overhead-at-end 0 :internal-dur-at-end 139 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3234 :pcs-gap 0 ) false 1 0 Using ephemeris for target 11556-10-PLUTO-SYSTEM ephemeris data for target 11556-10-PLUTO-SYSTEM does not cover planning interval. Physical constraints are assumed to be unschedulable outside of the ephemeris data. Planning interval: 08.306 to 11.001. ephemeris interval: 09.151 to 11.152 Timing link suitability includes constraints ([10 After 01 by 91.3 to 91.8 days]) The scheduling data was generated by CASM 17.2. CASM was run in Phase II mode. (Tic-Visit :proposal-id 11556 :visit-id "10" :proposal-version -1 :trans-version "20091209" :date "29-Jan-2010 07:06:41.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "29" :si-bright-earth-limb-angle 20.0 :data-volume 91536 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 11556 :visit-id "10" :obset-id "10" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 11556 :visit-id "10" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2819 :al-overhead-at-end 0 :internal-dur-at-end 139 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3234 :pcs-gap 0 ) false 1 0 Using ephemeris for target 11556-11-PLUTO-SYSTEM ephemeris data for target 11556-11-PLUTO-SYSTEM does not cover planning interval. Physical constraints are assumed to be unschedulable outside of the ephemeris data. Planning interval: 08.306 to 11.001. ephemeris interval: 09.151 to 11.152 Timing link suitability includes constraints ([11 After 01 by 112.1 to 112.6 days]) The scheduling data was generated by CASM 17.2. CASM was run in Phase II mode. (Tic-Visit :proposal-id 11556 :visit-id "11" :proposal-version -1 :trans-version "20091209" :date "29-Jan-2010 07:06:48.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "29" :si-bright-earth-limb-angle 20.0 :data-volume 91536 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 11556 :visit-id "11" :obset-id "11" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 11556 :visit-id "11" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2819 :al-overhead-at-end 0 :internal-dur-at-end 139 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3234 :pcs-gap 0 ) false 1 0 Using ephemeris for target 11556-12-PLUTO-SYSTEM ephemeris data for target 11556-12-PLUTO-SYSTEM does not cover planning interval. Physical constraints are assumed to be unschedulable outside of the ephemeris data. Planning interval: 08.306 to 11.001. ephemeris interval: 09.151 to 11.152 Timing link suitability includes constraints ([12 After 01 by 134.9 to 135.4 days]) The scheduling data was generated by CASM 17.2. CASM was run in Phase II mode. (Tic-Visit :proposal-id 11556 :visit-id "12" :proposal-version -1 :trans-version "20091209" :date "29-Jan-2010 07:06:54.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "29" :si-bright-earth-limb-angle 20.0 :data-volume 91536 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 11556 :visit-id "12" :obset-id "12" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 11556 :visit-id "12" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2819 :al-overhead-at-end 0 :internal-dur-at-end 139 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3234 :pcs-gap 0 ) false 1 0