The subset of transneptunian objects (TNOs) having natural satellites offers unique opportunities for physical studies of these distant relics from the outer parts of the protoplanetary nebula. HST/ACS is ideally suited to determining orbits of TNO satellites, resulting in the system masses. In conjunction with thermal emission observations by Spitzer, which provides sizes, we can determine the densities of TNOs. Densities offer a powerful window into their bulk compositions and interior structures.

Two visits to the 1st target are scheduled as early as possible in Cycle 14, in order to leave time for a follow-up observation to be scheduled during the remainder of the 2005 apparition (which ends in early September). Note: if we've constrained the first two visits so tightly that they're not schedulable, please contact us. We could relax the timing constraints somewhat without wrecking the experiment. The other 2 targets will get scheduled pending confirmation of their binary status, most likely with the 1st two visits being activated together, followed by the remaining two visits being scheduled after analysis of data from the 1st 2 visits. SOLAR SYSTEM 12 false 0 0.0 false 0 false false false false SUPPORTED SOLAR SYSTEM ASTEROID cold classical TYPE=ASTEROID,A=42.79558262,E=0.05101959,I=3.77183,O=104.22046,W=35.81372,M=180.91633,EQUINOX=J2000,EPOCH=24-AUG-2000:00:00:00 A_VEL 2003QY90 FROM EARTH GT 0.00005 SOLAR SYSTEM ASTEROID (42355) 2002 CR46 TYPE=ASTEROID,A=38.112041389,E=0.5401516,I=2.4286678,O=351.9872969,W=159.0246487,M=0.113753,EQUINOX=J2000,EPOCH=14-JUN-2006:00:00:00 SOLAR SYSTEM ASTEROID TNO TYPE=ASTEROID,A=102.87588697,E=0.82633281,I=22.2725924,O=171.9358773,W=320.0908497,M=5.8075731,EQUINOX=J2000,EPOCH=14-JUN-2006:00:00:00 SOLAR SYSTEM ASTEROID 2003QY90 improved ephemeris TYPE=ASTEROID,A=42.79250247,E=0.05106278,I=3.77164,O=104.21811,W=36.09316,M=180.60991,EQUINOX=J2000,EPOCH=24-AUG-2000:00:00:00 SOLAR SYSTEM ASTEROID 2002CR46 improved ephemeris TYPE=ASTEROID,A=38.112152452,E=0.54015273,I=2.42868,O=351.9869701,W=159.0249012,M=0.11377,EQUINOX=J2000,EPOCH=14-JUN-2006:00:00:00 ACS/HRC Imaging No No F606W ACS/HRC Imaging No No F814W ACS/HRC Imaging No No F606W ACS/HRC Imaging No No F814W ACS/HRC Imaging No No F606W ACS/HRC Imaging No No F814W ACS/HRC Imaging No No F606W ACS/HRC Imaging No No F814W ACS/HRC Imaging No No F606W ACS/HRC Imaging No No F814W ACS/HRC Imaging No No F606W ACS/HRC Imaging No No F814W ACS/HRC Imaging No No F606W ACS/HRC Imaging No No F814W ACS/HRC Imaging No No F606W ACS/HRC Imaging No No F814W ACS/HRC Imaging No No F606W ACS/HRC Imaging No No F814W ACS/HRC Imaging No No F606W ACS/HRC Imaging No No F814W ACS/HRC Imaging No No F606W ACS/HRC Imaging No No F814W ACS/HRC Imaging No No F606W ACS/HRC Imaging No No F814W POS-TARG DITHER 0.198 LINE false true 2 44.279999 ACS-HRC-DITHER-LINE 1 false POS-TARG DITHER 0.198 LINE false true 2 134.279999 ACS-HRC-DITHER-LINE 2 false (Tic-Visit :proposal-id 10508 :visit-id "01" :proposal-version -1 :trans-version "20050502" :date "13-Jul-2005 15:42:13.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "27" :si-bright-earth-limb-angle 20.0 :data-volume 147216 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 10508 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 10508 :visit-id "01" :orbit-number 1 :pcs-time 367 :si-vis-utilization 2604 :al-overhead-at-end 0 :internal-dur-at-end 199 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3028 :pcs-gap 0 ) false 1 0 (Tic-Visit :proposal-id 10508 :visit-id "02" :proposal-version -1 :trans-version "20050502" :date "13-Jul-2005 15:27:38.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "27" :si-bright-earth-limb-angle 20.0 :data-volume 147216 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 10508 :visit-id "02" :obset-id "02" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 10508 :visit-id "02" :orbit-number 1 :pcs-time 367 :si-vis-utilization 2604 :al-overhead-at-end 0 :internal-dur-at-end 199 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3028 :pcs-gap 0 ) false 1 0 (Tic-Visit :proposal-id 10508 :visit-id "03" :proposal-version -1 :trans-version "20050502" :date "13-Jul-2005 15:27:56.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "27" :si-bright-earth-limb-angle 20.0 :data-volume 147216 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 10508 :visit-id "03" :obset-id "03" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 10508 :visit-id "03" :orbit-number 1 :pcs-time 367 :si-vis-utilization 2604 :al-overhead-at-end 0 :internal-dur-at-end 199 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3028 :pcs-gap 0 ) false 1 0 To be triggered by investigators (Tic-Visit :proposal-id 10508 :visit-id "04" :proposal-version -1 :trans-version "20050502" :date "13-Jul-2005 15:28:06.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "27" :si-bright-earth-limb-angle 20.0 :data-volume 147216 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 10508 :visit-id "04" :obset-id "04" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 10508 :visit-id "04" :orbit-number 1 :pcs-time 367 :si-vis-utilization 2604 :al-overhead-at-end 0 :internal-dur-at-end 199 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3028 :pcs-gap 0 ) false 1 0 Pending computation of optimal follow-up timing Goal is to schedule this visit plus visit 6, both during the current visibility window, but separated by as much time as possible (at least 6 days). (Tic-Visit :proposal-id 10508 :visit-id "05" :proposal-version -1 :trans-version "20050502" :date "13-Jul-2005 15:43:19.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "27" :si-bright-earth-limb-angle 20.0 :data-volume 147216 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 10508 :visit-id "05" :obset-id "05" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 10508 :visit-id "05" :orbit-number 1 :pcs-time 367 :si-vis-utilization 2604 :al-overhead-at-end 0 :internal-dur-at-end 199 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3028 :pcs-gap 0 ) false 1 0 Goal is to follow visit 5 by as long of a time span as possible within the constraints of 2-gyro scheduling during the current visibility window. (Tic-Visit :proposal-id 10508 :visit-id "06" :proposal-version -1 :trans-version "20051113" :date "01-Feb-2006 14:56:08.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "27" :si-bright-earth-limb-angle 20.0 :data-volume 147216 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 10508 :visit-id "06" :obset-id "06" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 10508 :visit-id "06" :orbit-number 1 :pcs-time 339 :si-vis-utilization 2604 :al-overhead-at-end 0 :internal-dur-at-end 199 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3028 :pcs-gap 0 ) false 1 0 To be triggered by investigators (Tic-Visit :proposal-id 10508 :visit-id "07" :proposal-version -1 :trans-version "20050502" :date "13-Jul-2005 15:43:39.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "27" :si-bright-earth-limb-angle 20.0 :data-volume 147216 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 10508 :visit-id "07" :obset-id "07" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 10508 :visit-id "07" :orbit-number 1 :pcs-time 367 :si-vis-utilization 2604 :al-overhead-at-end 0 :internal-dur-at-end 199 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3028 :pcs-gap 0 ) false 1 0 Pending target confirmation To be triggered by investigators (Tic-Visit :proposal-id 10508 :visit-id "08" :proposal-version -1 :trans-version "20050502" :date "13-Jul-2005 15:43:48.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "27" :si-bright-earth-limb-angle 20.0 :data-volume 147216 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 10508 :visit-id "08" :obset-id "08" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 10508 :visit-id "08" :orbit-number 1 :pcs-time 367 :si-vis-utilization 2604 :al-overhead-at-end 0 :internal-dur-at-end 199 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3028 :pcs-gap 0 ) false 1 0 Pending target confirmation To be triggered by investigators (Tic-Visit :proposal-id 10508 :visit-id "09" :proposal-version -1 :trans-version "20050502" :date "13-Jul-2005 15:43:56.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "27" :si-bright-earth-limb-angle 20.0 :data-volume 147216 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 10508 :visit-id "09" :obset-id "09" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 10508 :visit-id "09" :orbit-number 1 :pcs-time 367 :si-vis-utilization 2604 :al-overhead-at-end 0 :internal-dur-at-end 199 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3028 :pcs-gap 0 ) false 1 0 Pending target confirmation To be triggered by investigators (Tic-Visit :proposal-id 10508 :visit-id "10" :proposal-version -1 :trans-version "20050502" :date "13-Jul-2005 15:44:02.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "27" :si-bright-earth-limb-angle 20.0 :data-volume 147216 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 10508 :visit-id "10" :obset-id "10" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 10508 :visit-id "10" :orbit-number 1 :pcs-time 367 :si-vis-utilization 2604 :al-overhead-at-end 0 :internal-dur-at-end 199 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3028 :pcs-gap 0 ) false 1 0 Pending target confirmation To be triggered by investigators (Tic-Visit :proposal-id 10508 :visit-id "11" :proposal-version -1 :trans-version "20050502" :date "13-Jul-2005 15:44:14.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "27" :si-bright-earth-limb-angle 20.0 :data-volume 147216 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 10508 :visit-id "11" :obset-id "11" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 10508 :visit-id "11" :orbit-number 1 :pcs-time 367 :si-vis-utilization 2604 :al-overhead-at-end 0 :internal-dur-at-end 199 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3028 :pcs-gap 0 ) false 1 0 Pending target confirmation To be triggered by investigators (Tic-Visit :proposal-id 10508 :visit-id "12" :proposal-version -1 :trans-version "20050502" :date "13-Jul-2005 15:44:19.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "27" :si-bright-earth-limb-angle 20.0 :data-volume 147216 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 10508 :visit-id "12" :obset-id "12" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 10508 :visit-id "12" :orbit-number 1 :pcs-time 367 :si-vis-utilization 2604 :al-overhead-at-end 0 :internal-dur-at-end 199 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3028 :pcs-gap 0 ) false 1 0 Pending target confirmation Repeat of failed visit 08. (Tic-Visit :proposal-id 10508 :visit-id "08" :proposal-version -1 :trans-version "20050502" :date "13-Jul-2005 15:43:48.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "27" :si-bright-earth-limb-angle 20.0 :data-volume 147216 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 10508 :visit-id "08" :obset-id "08" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 10508 :visit-id "08" :orbit-number 1 :pcs-time 367 :si-vis-utilization 2604 :al-overhead-at-end 0 :internal-dur-at-end 199 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3028 :pcs-gap 0 ) false 1 0