Orbital Evolution and Stability of the Inner Uranian Moons

Orbital Evolution and Stability of the Inner Uranian Moons Nine densely-packed inner moons of Uranus show signs of chaos and orbital instability over a variety of time scales. Many moons show measureable orbital changes within a decade or less. Long-term integrations predict that some moons could collide in less than one million years. One faint ring embedded in the system may, in fact, be the debris left behind from an earlier such collision. Meanwhile, the nearby moon Mab falls well outside the influence of the others but nevertheless shows rapid, as yet unexplained, changes in its orbit. It is embedded within a dust ring that also shows surprising variability. A highly optimized series of observations with WFC3 over the next three cycles will address some of the fundamental open questions about this dynamically active system: Do the orbits truly show evidence of chaos? If so, over what time scales? What can we say about the masses of the moons involved? What is the nature of the variations in Mab's orbit? Is Mab's motion predictable or random? Astrometry will enable us to derive the orbital elements of these moons with 10-km precision. This will be sufficient to study the year-by-year changes and, combined with other data from 2003-2007, the decadal evolution of the orbits. The pairing of precise astrometry with numerical integrations will enable us to derive new dynamical constraints on the masses of these moons. Mass is the fundamental unknown quantity currently limiting our ability to reproduce the interactions within this system. This program will also capitalize upon our best opportunity for nearly 40 years to study the unexplained variations in Uranus's faint outer rings.

Astrometry of the Uranian satellites is accomplished via eight visits, each consisting of a sequence of long exposures through the broad F606W filter. Each orbit begins with one unsaturated image of the planet for geometric reference and calibration checking. The orbital plane is oriented within 20 degrees of the X-axis in the images to separate the moons from the wide vertical band caused by saturation bloom from the planet. From orbit to orbit, Uranus is shifted upward and downward by ~ 40 pixels within the 512x512 subarray to achieve some of the benefits of dithering; however, moons can always be distinguished from hot pixels by their motion. Each visit is timed to place one of the smallest moons near its maximum orbital elonagation, because this is where such moons are most detectable. The larger moons will be captured by chance and require no special targeting. Mab is the target of repeated observations in order to study its orbital variations. A ninth visit will be used to determine the color of Mab and that of its neighboring moons, Puck and Miranda. With measurements spanning blue to the IR, it will be possible to determine which of the two neighbors most resembles Mab, and thereby reduce the large uncertainties in Mab's albedo and size. SOLAR SYSTEM 12 false 0.0 0.0 false false false false false false SUPPORTED SOLAR SYSTEM PLANET Uranus with Perdita near its maximum southern elongation; Mab also visible STD=URANUS OLG OF PERDITA BETWEEN 70 110, SEP OF PERDITA ARIEL FROM EARTH GT 4", SEP OF PERDITA UMBRIEL FROM EARTH GT 4", SEP OF PERDITA TITANIA FROM EARTH GT 5", SEP OF PERDITA OBERON FROM EARTH GT 5", SEP OF PERDITA MIRANDA FROM EARTH GT 4", SEP OF PERDITA PUCK FROM EARTH GT 2", SEP OF PERDITA BELINDA FROM EARTH GT 1", NOT OLG OF MAB BETWEEN 0 45, NOT OLG OF MAB BETWEEN 135 225, NOT OLG OF MAB BETWEEN 315 360 EARTH SOLAR SYSTEM PLANET Uranus with Perdita near its maximum northern elongation; Mab also visible STD=URANUS OLG OF PERDITA BETWEEN 250 290, SEP OF PERDITA ARIEL FROM EARTH GT 4", SEP OF PERDITA UMBRIEL FROM EARTH GT 4", SEP OF PERDITA TITANIA FROM EARTH GT 5", SEP OF PERDITA OBERON FROM EARTH GT 5", SEP OF PERDITA MIRANDA FROM EARTH GT 4", SEP OF PERDITA PUCK FROM EARTH GT 2", SEP OF PERDITA BELINDA FROM EARTH GT 1", NOT OLG OF MAB BETWEEN 0 45, NOT OLG OF MAB BETWEEN 135 225, NOT OLG OF MAB BETWEEN 315 360 EARTH SOLAR SYSTEM PLANET Uranus with Mab near its maximum southern elongation STD=URANUS OLG OF MAB BETWEEN 60 120, SEP OF MAB ARIEL FROM EARTH GT 4", SEP OF MAB UMBRIEL FROM EARTH GT 4", SEP OF MAB TITANIA FROM EARTH GT 5", SEP OF MAB OBERON FROM EARTH GT 5", SEP OF MAB MIRANDA FROM EARTH GT 4" EARTH SOLAR SYSTEM PLANET Uranus with Mab near its maximum northern elongation STD=URANUS OLG OF MAB BETWEEN 240 300, SEP OF MAB ARIEL FROM EARTH GT 4", SEP OF MAB UMBRIEL FROM EARTH GT 4", SEP OF MAB TITANIA FROM EARTH GT 5", SEP OF MAB OBERON FROM EARTH GT 5", SEP OF MAB MIRANDA FROM EARTH GT 4" EARTH SOLAR SYSTEM PLANET Uranus with Cupid near its maximum southern elongation; Mab also visible STD=URANUS OLG OF CUPID BETWEEN 70 110, SEP OF CUPID ARIEL FROM EARTH GT 4", SEP OF CUPID UMBRIEL FROM EARTH GT 4", SEP OF CUPID TITANIA FROM EARTH GT 5", SEP OF CUPID OBERON FROM EARTH GT 5", SEP OF CUPID MIRANDA FROM EARTH GT 4", SEP OF CUPID PUCK FROM EARTH GT 2", SEP OF CUPID BELINDA FROM EARTH GT 1", NOT OLG OF MAB BETWEEN 0 45, NOT OLG OF MAB BETWEEN 135 225, NOT OLG OF MAB BETWEEN 315 360 EARTH SOLAR SYSTEM PLANET Uranus with Cupid near its maximum northern elongation; Mab also visible STD=URANUS OLG OF CUPID BETWEEN 250 290, SEP OF CUPID ARIEL FROM EARTH GT 4", SEP OF CUPID UMBRIEL FROM EARTH GT 4", SEP OF CUPID TITANIA FROM EARTH GT 5", SEP OF CUPID OBERON FROM EARTH GT 5", SEP OF CUPID MIRANDA FROM EARTH GT 4", SEP OF CUPID PUCK FROM EARTH GT 2", SEP OF CUPID BELINDA FROM EARTH GT 1", NOT OLG OF MAB BETWEEN 0 45, NOT OLG OF MAB BETWEEN 135 225, NOT OLG OF MAB BETWEEN 315 360 EARTH SOLAR SYSTEM PLANET Uranus with Mab, Puck and Miranda all visible STD=URANUS NOT OLG OF MAB BETWEEN 0 60, SEP OF MAB ARIEL FROM EARTH GT 5", SEP OF MAB UMBRIEL FROM EARTH GT 5", SEP OF MAB TITANIA FROM EARTH GT 5", SEP OF MAB OBERON FROM EARTH GT 5", SEP OF MAB MIRANDA FROM EARTH GT 5", NOT OLG OF MAB BETWEEN 120 240, NOT OLG OF MAB BETWEEN 300 360, SEP OF MAB PUCK FROM EARTH GT 3", NOT OLG OF PUCK BETWEEN 0 45, NOT OLG OF PUCK BETWEEN 135 225, NOT OLG OF PUCK BETWEEN 315 360, NOT OLG OF MIRANDA BETWEEN 0 15, NOT OLG OF MIRANDA BETWEEN 165 195, NOT OLG OF MIRANDA BETWEEN 345 360 EARTH SOLAR SYSTEM PLANET Uranus with Perdita near its maximum southern elongation STD=URANUS OLG OF PERDITA BETWEEN 70 110, SEP OF PERDITA ARIEL FROM EARTH GT 4", SEP OF PERDITA UMBRIEL FROM EARTH GT 4", SEP OF PERDITA TITANIA FROM EARTH GT 5", SEP OF PERDITA OBERON FROM EARTH GT 5", SEP OF PERDITA MIRANDA FROM EARTH GT 4", SEP OF PERDITA PUCK FROM EARTH GT 2", SEP OF PERDITA BELINDA FROM EARTH GT 1" EARTH SOLAR SYSTEM PLANET Uranus with Perdita near its maximum northern elongation STD=URANUS OLG OF PERDITA BETWEEN 250 290, SEP OF PERDITA ARIEL FROM EARTH GT 4", SEP OF PERDITA UMBRIEL FROM EARTH GT 4", SEP OF PERDITA TITANIA FROM EARTH GT 5", SEP OF PERDITA OBERON FROM EARTH GT 5", SEP OF PERDITA MIRANDA FROM EARTH GT 4", SEP OF PERDITA PUCK FROM EARTH GT 2", SEP OF PERDITA BELINDA FROM EARTH GT 1" EARTH SOLAR SYSTEM PLANET Uranus with Cupid near its maximum southern elongation STD=URANUS OLG OF CUPID BETWEEN 70 110, SEP OF CUPID ARIEL FROM EARTH GT 4", SEP OF CUPID UMBRIEL FROM EARTH GT 4", SEP OF CUPID TITANIA FROM EARTH GT 5", SEP OF CUPID OBERON FROM EARTH GT 5", SEP OF CUPID MIRANDA FROM EARTH GT 4", SEP OF CUPID PUCK FROM EARTH GT 2", SEP OF CUPID BELINDA FROM EARTH GT 1" EARTH SOLAR SYSTEM PLANET Uranus with Cupid near its maximum northern elongation STD=URANUS OLG OF CUPID BETWEEN 250 290, SEP OF CUPID ARIEL FROM EARTH GT 4", SEP OF CUPID UMBRIEL FROM EARTH GT 4", SEP OF CUPID TITANIA FROM EARTH GT 5", SEP OF CUPID OBERON FROM EARTH GT 5", SEP OF CUPID MIRANDA FROM EARTH GT 4", SEP OF CUPID PUCK FROM EARTH GT 2", SEP OF CUPID BELINDA FROM EARTH GT 1" EARTH WFC3/UVIS Imaging No No F606W WFC3/UVIS Imaging No No F390W WFC3/UVIS Imaging No No F467M WFC3/UVIS Imaging No No F475W WFC3/UVIS Imaging No No F621M WFC3/UVIS Imaging No No F814W WFC3/UVIS Imaging No No F845M WFC3/IR Imaging No No F105W WFC3/IR Imaging No No F125W WFC3/IR Imaging No No F160W Using ephemeris for target 12245-01-URANUS-PERDITA-SOUTH-MAB ephemeris data for target 12245-01-URANUS-PERDITA-SOUTH-MAB does not cover planning interval. Physical constraints are assumed to be unschedulable outside of the ephemeris data. Planning interval: 10.108 to 12.060. ephemeris interval: 10.212 to 12.214 The scheduling data was generated by CASM 18.3.1. CASM was run in Phase II mode. Uranus timed to position Perdita near its southern orbital elongation. Mab is also visible. The ring plane is oriented within 20 degrees of horizontal. 1286417308000 39.29016886813801 (Tic-Visit :proposal-id 12245 :visit-id "01" :proposal-version -1 :trans-version "20100505" :date "21-Aug-2010 10:49:40.0" :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 41200 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12245 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12245 :visit-id "01" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2685 :al-overhead-at-end 0 :internal-dur-at-end 84 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3021 :pcs-gap 0 ) true 1 0 Using ephemeris for target 12245-02-URANUS-PERDITA-NORTH-MAB ephemeris data for target 12245-02-URANUS-PERDITA-NORTH-MAB does not cover planning interval. Physical constraints are assumed to be unschedulable outside of the ephemeris data. Planning interval: 10.108 to 12.060. ephemeris interval: 10.212 to 12.214 The scheduling data was generated by CASM 18.3.1. CASM was run in Phase II mode. Uranus timed to position Perdita near its northern orbital elongation. Mab is also visible. The ring plane is oriented within 20 degrees of horizontal. 1287049942000 46.0 (Tic-Visit :proposal-id 12245 :visit-id "02" :proposal-version -1 :trans-version "20100505" :date "21-Aug-2010 10:49:41.0" :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 41200 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12245 :visit-id "02" :obset-id "02" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12245 :visit-id "02" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2675 :al-overhead-at-end 0 :internal-dur-at-end 84 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3021 :pcs-gap 0 ) true 1 0 Using ephemeris for target 12245-03-URANUS-MAB-SOUTH ephemeris data for target 12245-03-URANUS-MAB-SOUTH does not cover planning interval. Physical constraints are assumed to be unschedulable outside of the ephemeris data. Planning interval: 10.108 to 12.060. ephemeris interval: 10.212 to 12.214 Timing link suitability includes constraints ([04 After 03 by 4.0 to 10.0 days]) The scheduling data was generated by CASM 18.3.1. CASM was run in Phase II mode. Uranus timed to position Mab near its southern orbital elongation. The ring plane is oriented within 20 degrees of horizontal. Schedule early in observing window, preferably before September 18. 1284294934000 223.40871607165752 (Tic-Visit :proposal-id 12245 :visit-id "03" :proposal-version -1 :trans-version "20100505" :date "21-Aug-2010 10:49:42.0" :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 41200 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12245 :visit-id "03" :obset-id "03" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12245 :visit-id "03" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2685 :al-overhead-at-end 0 :internal-dur-at-end 84 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3021 :pcs-gap 0 ) true 1 0 Using ephemeris for target 12245-04-URANUS-MAB-NORTH ephemeris data for target 12245-04-URANUS-MAB-NORTH does not cover planning interval. Physical constraints are assumed to be unschedulable outside of the ephemeris data. Planning interval: 10.108 to 12.060. ephemeris interval: 10.212 to 12.214 Timing link suitability includes constraints ([04 After 03 by 4.0 to 10.0 days] [13 After 04 by 14.0 to 28.0 days]) The scheduling data was generated by CASM 18.3.1. CASM was run in Phase II mode. Uranus timed to position Mab near its northern orbital elongation. The ring plane is oriented within 20 degrees of horizontal. Shedule 4-10 days after Visit 03. 1285128835000 43.04625263213009 (Tic-Visit :proposal-id 12245 :visit-id "04" :proposal-version -1 :trans-version "20100505" :date "21-Aug-2010 10:49:43.0" :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 41200 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12245 :visit-id "04" :obset-id "04" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12245 :visit-id "04" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2668 :al-overhead-at-end 0 :internal-dur-at-end 84 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3021 :pcs-gap 0 ) true 1 0 Using ephemeris for target 12245-13-URANUS-MAB-SOUTH ephemeris data for target 12245-13-URANUS-MAB-SOUTH does not cover planning interval. Physical constraints are assumed to be unschedulable outside of the ephemeris data. Planning interval: 10.108 to 12.060. ephemeris interval: 10.212 to 12.214 Timing link suitability includes constraints ([13 After 04 by 14.0 to 28.0 days]) The scheduling data was generated by CASM 18.3.1. CASM was run in Phase II mode. Uranus timed to position Mab near its southern orbital elongation. The ring plane is oriented within 20 degrees of horizontal. Schedule 14-28 days after Visit 04. 1287003936000 46.0 (Tic-Visit :proposal-id 12245 :visit-id "13" :proposal-version -1 :trans-version "20100505" :date "21-Aug-2010 10:49:44.0" :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 41200 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12245 :visit-id "13" :obset-id "13" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12245 :visit-id "13" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2685 :al-overhead-at-end 0 :internal-dur-at-end 84 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3021 :pcs-gap 0 ) true 1 0 Using ephemeris for target 12245-14-URANUS-MAB-NORTH ephemeris data for target 12245-14-URANUS-MAB-NORTH does not cover planning interval. Physical constraints are assumed to be unschedulable outside of the ephemeris data. Planning interval: 10.108 to 12.060. ephemeris interval: 10.212 to 12.214 The scheduling data was generated by CASM 18.3.1. CASM was run in Phase II mode. Uranus timed to position Mab near its northern orbital elongation. The ring plane is oriented within 20 degrees of horizontal. Shedule near the end of the observing window, preferably after 1 November, 2010. (Tic-Visit :proposal-id 12245 :visit-id "14" :proposal-version -1 :trans-version "20100505" :date "21-Aug-2010 10:49:44.0" :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 41200 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12245 :visit-id "14" :obset-id "14" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12245 :visit-id "14" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2675 :al-overhead-at-end 0 :internal-dur-at-end 84 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3021 :pcs-gap 0 ) true 1 0 Using ephemeris for target 12245-05-URANUS-CUPID-SOUTH-MAB ephemeris data for target 12245-05-URANUS-CUPID-SOUTH-MAB does not cover planning interval. Physical constraints are assumed to be unschedulable outside of the ephemeris data. Planning interval: 10.108 to 12.060. ephemeris interval: 10.212 to 12.214 The scheduling data was generated by CASM 18.3.1. CASM was run in Phase II mode. Uranus timed to position Cupid near its southern orbital elongation. Mab is also visible. The ring plane is oriented within 20 degrees of horizontal. 1284220196000 226.0 (Tic-Visit :proposal-id 12245 :visit-id "05" :proposal-version -1 :trans-version "20100505" :date "21-Aug-2010 10:49:45.0" :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 41200 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12245 :visit-id "05" :obset-id "05" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12245 :visit-id "05" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2685 :al-overhead-at-end 0 :internal-dur-at-end 84 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3021 :pcs-gap 0 ) true 1 0 Using ephemeris for target 12245-06-URANUS-CUPID-NORTH-MAB ephemeris data for target 12245-06-URANUS-CUPID-NORTH-MAB does not cover planning interval. Physical constraints are assumed to be unschedulable outside of the ephemeris data. Planning interval: 10.108 to 12.060. ephemeris interval: 10.212 to 12.214 The scheduling data was generated by CASM 18.3.1. CASM was run in Phase II mode. Uranus timed to position Cupid near its northern orbital elongation. Mab is also visible. The ring plane is oriented within 20 degrees of horizontal. (Tic-Visit :proposal-id 12245 :visit-id "06" :proposal-version -1 :trans-version "20100505" :date "21-Aug-2010 10:49:46.0" :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 41200 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12245 :visit-id "06" :obset-id "06" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12245 :visit-id "06" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2668 :al-overhead-at-end 0 :internal-dur-at-end 84 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3021 :pcs-gap 0 ) true 1 0 Using ephemeris for target 12245-07-URANUS-MAB-PUCK-MIRANDA ephemeris data for target 12245-07-URANUS-MAB-PUCK-MIRANDA does not cover planning interval. Physical constraints are assumed to be unschedulable outside of the ephemeris data. Planning interval: 10.108 to 12.060. ephemeris interval: 10.212 to 12.214 The scheduling data was generated by CASM 18.3.1. CASM was run in Phase II mode. UVIS and IR color measurements of Mab, Puck and Miranda. The ring plane is oriented within 20 degrees of horizontal. Bracketing to ensure un-saturated images of Miranda, plus respectable detections of Mab (signal-to-noise > ~ 10). Schedule as close as possible to opposition (September 21, 2010). 1287009687000 46.0 (Tic-Visit :proposal-id 12245 :visit-id "07" :proposal-version -1 :trans-version "20100505" :date "21-Aug-2010 10:37:12.0" :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 124672 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12245 :visit-id "07" :obset-id "07" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12245 :visit-id "07" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2682 :al-overhead-at-end 0 :internal-dur-at-end 226 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3021 :pcs-gap 0 ) false 1 0 Using ephemeris for target 12245-11-URANUS-PERDITA-SOUTH ephemeris data for target 12245-11-URANUS-PERDITA-SOUTH does not cover planning interval. Physical constraints are assumed to be unschedulable outside of the ephemeris data. Planning interval: 10.108 to 12.060. ephemeris interval: 10.212 to 12.214 The scheduling data was generated by CASM 18.3.1. CASM was run in Phase II mode. Uranus timed to position Perdita near its southern orbital elongation. The ring plane is oriented within 20 degrees of horizontal. (Tic-Visit :proposal-id 12245 :visit-id "11" :proposal-version -1 :trans-version "20100505" :date "21-Aug-2010 10:49:47.0" :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 41200 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12245 :visit-id "11" :obset-id "11" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12245 :visit-id "11" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2685 :al-overhead-at-end 0 :internal-dur-at-end 84 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3021 :pcs-gap 0 ) true 1 0 Use as an alternative to Visit 01, if Visit 01 (with additional constraints on the orbital position of Mab) is too difficult to schedule. Using ephemeris for target 12245-12-URANUS-PERDITA-NORTH ephemeris data for target 12245-12-URANUS-PERDITA-NORTH does not cover planning interval. Physical constraints are assumed to be unschedulable outside of the ephemeris data. Planning interval: 10.108 to 12.060. ephemeris interval: 10.212 to 12.214 The scheduling data was generated by CASM 18.3.1. CASM was run in Phase II mode. Uranus timed to position Perdita near its northern orbital elongation. The ring plane is oriented within 20 degrees of horizontal. (Tic-Visit :proposal-id 12245 :visit-id "12" :proposal-version -1 :trans-version "20100505" :date "21-Aug-2010 10:49:47.0" :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 41200 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12245 :visit-id "12" :obset-id "12" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12245 :visit-id "12" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2675 :al-overhead-at-end 0 :internal-dur-at-end 84 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3021 :pcs-gap 0 ) true 1 0 Use as an alternative to Visit 02, if Visit 02 (with additional constraints on the orbital postion of Mab) is too difficult to schedule. Using ephemeris for target 12245-15-URANUS-CUPID-SOUTH ephemeris data for target 12245-15-URANUS-CUPID-SOUTH does not cover planning interval. Physical constraints are assumed to be unschedulable outside of the ephemeris data. Planning interval: 10.108 to 12.060. ephemeris interval: 10.212 to 12.214 The scheduling data was generated by CASM 18.3.1. CASM was run in Phase II mode. Uranus timed to position Cupid near its southern orbital elongation. The ring plane is oriented within 20 degrees of horizontal. (Tic-Visit :proposal-id 12245 :visit-id "15" :proposal-version -1 :trans-version "20100505" :date "21-Aug-2010 10:49:48.0" :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 41200 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12245 :visit-id "15" :obset-id "15" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12245 :visit-id "15" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2685 :al-overhead-at-end 0 :internal-dur-at-end 84 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3021 :pcs-gap 0 ) true 1 0 Use as an alternative to Visit 05, if Visit 05 (with its additional constraints on the orbital position of Mab) is too difficult to schedule. Using ephemeris for target 12245-16-URANUS-CUPID-NORTH ephemeris data for target 12245-16-URANUS-CUPID-NORTH does not cover planning interval. Physical constraints are assumed to be unschedulable outside of the ephemeris data. Planning interval: 10.108 to 12.060. ephemeris interval: 10.212 to 12.214 The scheduling data was generated by CASM 18.3.1. CASM was run in Phase II mode. Uranus timed to position Cupid near its northern orbital elongation. The ring plane is oriented within 20 degrees of horizontal. 1285146190000 38.440352876156595 (Tic-Visit :proposal-id 12245 :visit-id "16" :proposal-version -1 :trans-version "20100505" :date "21-Aug-2010 10:49:49.0" :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 41200 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12245 :visit-id "16" :obset-id "16" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12245 :visit-id "16" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2668 :al-overhead-at-end 0 :internal-dur-at-end 84 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3021 :pcs-gap 0 ) true 1 0 Use as an alternative to Visit 06, if Visit 06 (with additional constraints on the orbital position of Mab) is too difficult to schedule. Repeat of failed visit 05. Uranus timed to position Cupid near its southern orbital elongation. Mab is also visible. The ring plane is oriented within 20 degrees of horizontal. (Tic-Visit :proposal-id 12245 :visit-id "05" :proposal-version -1 :trans-version "20100505" :date "21-Aug-2010 10:49:45.0" :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 41200 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12245 :visit-id "05" :obset-id "05" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12245 :visit-id "05" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2685 :al-overhead-at-end 0 :internal-dur-at-end 84 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3021 :pcs-gap 0 ) false 1 0