15233( 5) - 04-Jun-2018 16:51:32 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 15233 Version: 5 Check-in Time: 04-Jun-2018 16:51:32 STScI Edit Number: 1 Title Density of transneptunian object 229762 2007 UK126 ------------------------------------------------------------------------------------ Type Cycle GO 25 ------------------------------------------------------------------------------------ Investigators Contact? PI: Dr. Will M. Grundy Lowell Observatory Y CoI: Dr. Keith S. Noll NASA Goddard Space Flight Center N CoI: Dr. Marc W. Buie Southwest Research Institute N CoI: Prof. Darin Ragozzine Brigham Young University N ------------------------------------------------------------------------------------ Abstract Densities provide unique information about bulk composition and interior structure and are key to going beyond the skin-deep view offered by remote-sensing techniques based on photometry, spectroscopy, and polarimetry. They are known for a handful of the relict planetesimals that populate our Solar System's Kuiper belt, revealing intriguing differences between small and large bodies. More and better quality data are needed to address fundamental questions about how planetesimals form from nebular solids, and how distinct materials are distributed through the nebula. Masses from binary orbits are generally quite precise, but a problem afflicting many of the known densities is that they depend on size estimates from thermal emission observations, with large model-dependent uncertainties that dominate the error bars on density estimates. Stellar occultations can provide much more accurate sizes and thus densities, but they depend on fortuitous geometry and thus can only be done for a few particularly valuable binaries. We propose observations of a system where an accurate density can be determined: 229762 2007 UK126. An accurate size is already available from multiple stellar occultation chords. This proposal will determine the mass, and thus the density. ------------------------------------------------------------------------------------ Observations Description ------------------------ Observations for mutual orbit determination of a transneptunian binary. Our goal is to determine the mutual orbit and thus the mass. Since we don't know the orbit orientation or period, it is efficient to use a step-wise strategy. We will do an initial pair of observation visits, to be scheduled as early as convient. After those are done, we will use the information obtained in those two visits to optimize scheduling of the subsequent visit, and so on. The last 3 visits are accordingly marked as "on hold". This is the same approach as we have used in several previous programs, and we believe we can do it in such a way as to not impose difficulties on the schedulers, via close coordination with STScI staff. ------------------------------------------------------------------------------------ 15233( 5) - 04-Jun-2018 16:51:32 - [ 2] TARGET LIST Solar System Targets ------------------------------------------------------------------------------------------------------------------------------------ TARGET NUMBER: 1 TARGET NAME: 229762 ------------------------------------------------------------------------------------------------------------------------------------ TARGET DESCRIPTION: ASTEROID transneptunian binary system ------------------------------------------------------------------------------------------------------------------------------------ TARGET POSITION LEVEL 1 TARGET POSITION LEVEL 2 TYPE=ASTEROID, A=72.804064901, E=0.485230329260, I=23.368191827000, O=131.139657960000, W=346.936504680000, M=343.739036250000, EQUINOX=J2000, EPOCH=01-JUL-2018:00:00:00, EpochTimeScale=UTC ------------------------------------------------------------------------------------------------------------------------------------ TARGET POSITION LEVEL 3 WINDOWS ANGULAR_RATE 229762 FROM EARTH GT 0.0001 ------------------------------------------------------------------------------------------------------------------------------------ DATA COMMENTS V = 20 +/- 0.5 Ephemeris Center: EARTH ------------------------------------------------------------------------------------------------------------------------------------ 15233( 5) - 04-Jun-2018 16:51:32 - [ 3] Patterns ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 1 Primary_Pattern Secondary_Pattern Pattern_Type LINE Pattern_Purpose DITHER Number_Of_Points 2 Point_Spacing 0.145 Line_Spacing Coordinate_Frame POS-TARG Pattern_Orient 46.84 Angle_Between_Sides Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ 15233( 5) - 04-Jun-2018 16:51:32 - [ 4] Visit: 01 Visit Requirements: SCHED 30%; BETWEEN 15-DEC-2017:00:00:00 AND 10-JAN-2018:00:00:00 On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 229762 WFC3/UVI ACCUM UVIS2-C51 F606W FLASH=8.0, CR-SPLIT=NO 1 192 S (384 POS TARG -.1582, S 2C-SUB S) 0.0289867; PATTERN 1 1 ------------------------------------------------------------------------------------------------------------------------------------ 2 229762 WFC3/UVI ACCUM UVIS2-C51 F814W FLASH=10.0, CR-SPLIT=NO 1 326 S (652 POS TARG -0.153256, S 2C-SUB S) -0.144537; PATTERN 1 2 ------------------------------------------------------------------------------------------------------------------------------------ 3 229762 WFC3/UVI ACCUM UVIS2-C51 F814W FLASH=10.0, CR-SPLIT=NO 1 326 S (652 POS TARG 0.0541835, S 2C-SUB S) 0.0385166; PATTERN 1 3 ------------------------------------------------------------------------------------------------------------------------------------ 4 229762 WFC3/UVI ACCUM UVIS2-C51 F606W FLASH=8.0, CR-SPLIT=NO 1 192 S (384 POS TARG 0.0494375, S 2C-SUB S) -0.145331; PATTERN 1 4 ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ 229762 1 WFC3/UVI ACCUM UVIS2-C5 F606W 1 none none none 1 N/A S 12C-SUB 229762 1 WFC3/UVI ACCUM UVIS2-C5 F606W 2 none none none 1 N/A S 12C-SUB 229762 2 WFC3/UVI ACCUM UVIS2-C5 F814W 1 none none none 1 N/A S 12C-SUB 229762 2 WFC3/UVI ACCUM UVIS2-C5 F814W 2 none none none 1 N/A S 12C-SUB 229762 3 WFC3/UVI ACCUM UVIS2-C5 F814W 1 none none none 1 N/A S 12C-SUB 229762 3 WFC3/UVI ACCUM UVIS2-C5 F814W 2 none none none 1 N/A S 12C-SUB 229762 4 WFC3/UVI ACCUM UVIS2-C5 F606W 1 none none none 1 N/A S 12C-SUB 229762 4 WFC3/UVI ACCUM UVIS2-C5 F606W 2 none none none 1 N/A S 12C-SUB 15233( 5) - 04-Jun-2018 16:51:32 - [ 5] Visit: 02 Visit Requirements: SCHED 30%; AFTER 01 BY 10 H TO 20 H On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 229762 WFC3/UVI ACCUM UVIS2-C51 F606W FLASH=8.0, CR-SPLIT=NO 1 192 S (384 POS TARG -.1582, S 2C-SUB S) 0.0289867; PATTERN 1 1 ------------------------------------------------------------------------------------------------------------------------------------ 2 229762 WFC3/UVI ACCUM UVIS2-C51 F814W FLASH=10.0, CR-SPLIT=NO 1 326 S (652 POS TARG -0.153256, S 2C-SUB S) -0.144537; PATTERN 1 2 ------------------------------------------------------------------------------------------------------------------------------------ 3 229762 WFC3/UVI ACCUM UVIS2-C51 F814W FLASH=10.0, CR-SPLIT=NO 1 326 S (652 POS TARG 0.0541835, S 2C-SUB S) 0.0385166; PATTERN 1 3 ------------------------------------------------------------------------------------------------------------------------------------ 4 229762 WFC3/UVI ACCUM UVIS2-C51 F606W FLASH=8.0, CR-SPLIT=NO 1 192 S (384 POS TARG 0.0494375, S 2C-SUB S) -0.145331; PATTERN 1 4 ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ 229762 1 WFC3/UVI ACCUM UVIS2-C5 F606W 1 none none none 1 N/A S 12C-SUB 229762 1 WFC3/UVI ACCUM UVIS2-C5 F606W 2 none none none 1 N/A S 12C-SUB 229762 2 WFC3/UVI ACCUM UVIS2-C5 F814W 1 none none none 1 N/A S 12C-SUB 229762 2 WFC3/UVI ACCUM UVIS2-C5 F814W 2 none none none 1 N/A S 12C-SUB 229762 3 WFC3/UVI ACCUM UVIS2-C5 F814W 1 none none none 1 N/A S 12C-SUB 229762 3 WFC3/UVI ACCUM UVIS2-C5 F814W 2 none none none 1 N/A S 12C-SUB 229762 4 WFC3/UVI ACCUM UVIS2-C5 F606W 1 none none none 1 N/A S 12C-SUB 229762 4 WFC3/UVI ACCUM UVIS2-C5 F606W 2 none none none 1 N/A S 12C-SUB 15233( 5) - 04-Jun-2018 16:51:32 - [ 6] Visit: 03 Visit Requirements: SCHED 30% On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 229762 WFC3/UVI ACCUM UVIS2-C51 F606W FLASH=8.0, CR-SPLIT=NO 1 192 S (384 POS TARG -.1582, S 2C-SUB S) 0.0289867; PATTERN 1 1 ------------------------------------------------------------------------------------------------------------------------------------ 2 229762 WFC3/UVI ACCUM UVIS2-C51 F814W FLASH=10.0, CR-SPLIT=NO 1 326 S (652 POS TARG -0.153256, S 2C-SUB S) -0.144537; PATTERN 1 2 ------------------------------------------------------------------------------------------------------------------------------------ 3 229762 WFC3/UVI ACCUM UVIS2-C51 F814W FLASH=10.0, CR-SPLIT=NO 1 326 S (652 POS TARG 0.0541835, S 2C-SUB S) 0.0385166; PATTERN 1 3 ------------------------------------------------------------------------------------------------------------------------------------ 4 229762 WFC3/UVI ACCUM UVIS2-C51 F606W FLASH=8.0, CR-SPLIT=NO 1 192 S (384 POS TARG 0.0494375, S 2C-SUB S) -0.145331; PATTERN 1 4 ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ 229762 1 WFC3/UVI ACCUM UVIS2-C5 F606W 1 none none none 1 N/A S 12C-SUB 229762 1 WFC3/UVI ACCUM UVIS2-C5 F606W 2 none none none 1 N/A S 12C-SUB 229762 2 WFC3/UVI ACCUM UVIS2-C5 F814W 1 none none none 1 N/A S 12C-SUB 229762 2 WFC3/UVI ACCUM UVIS2-C5 F814W 2 none none none 1 N/A S 12C-SUB 229762 3 WFC3/UVI ACCUM UVIS2-C5 F814W 1 none none none 1 N/A S 12C-SUB 229762 3 WFC3/UVI ACCUM UVIS2-C5 F814W 2 none none none 1 N/A S 12C-SUB 229762 4 WFC3/UVI ACCUM UVIS2-C5 F606W 1 none none none 1 N/A S 12C-SUB 229762 4 WFC3/UVI ACCUM UVIS2-C5 F606W 2 none none none 1 N/A S 12C-SUB 15233( 5) - 04-Jun-2018 16:51:32 - [ 7] Visit: 04 Visit Requirements: SCHED 30%; AFTER 03 BY 3 D TO 4 D On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 229762 WFC3/UVI ACCUM UVIS2-C51 F606W FLASH=8.0, CR-SPLIT=NO 1 192 S (384 POS TARG -.1582, S 2C-SUB S) 0.0289867; PATTERN 1 1 ------------------------------------------------------------------------------------------------------------------------------------ 2 229762 WFC3/UVI ACCUM UVIS2-C51 F438W FLASH=12.0, CR-SPLIT=NO 1 326 S (652 POS TARG -0.153256, S 2C-SUB S) -0.144537; PATTERN 1 2 ------------------------------------------------------------------------------------------------------------------------------------ 3 229762 WFC3/UVI ACCUM UVIS2-C51 F438W FLASH=12.0, CR-SPLIT=NO 1 326 S (652 POS TARG 0.0541835, S 2C-SUB S) 0.0385166; PATTERN 1 3 ------------------------------------------------------------------------------------------------------------------------------------ 4 229762 WFC3/UVI ACCUM UVIS2-C51 F606W FLASH=8.0, CR-SPLIT=NO 1 192 S (384 POS TARG 0.0494375, S 2C-SUB S) -0.145331; PATTERN 1 4 ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ 229762 1 WFC3/UVI ACCUM UVIS2-C5 F606W 1 none none none 1 N/A S 12C-SUB 229762 1 WFC3/UVI ACCUM UVIS2-C5 F606W 2 none none none 1 N/A S 12C-SUB 229762 2 WFC3/UVI ACCUM UVIS2-C5 F438W 1 none none none 1 N/A S 12C-SUB 229762 2 WFC3/UVI ACCUM UVIS2-C5 F438W 2 none none none 1 N/A S 12C-SUB 229762 3 WFC3/UVI ACCUM UVIS2-C5 F438W 1 none none none 1 N/A S 12C-SUB 229762 3 WFC3/UVI ACCUM UVIS2-C5 F438W 2 none none none 1 N/A S 12C-SUB 229762 4 WFC3/UVI ACCUM UVIS2-C5 F606W 1 none none none 1 N/A S 12C-SUB 229762 4 WFC3/UVI ACCUM UVIS2-C5 F606W 2 none none none 1 N/A S 12C-SUB 15233( 5) - 04-Jun-2018 16:51:32 - [ 8] Visit: 05 Visit Requirements: SCHED 30%; BETWEEN 02-AUG-2018:00:00:00 AND 07-AUG-2018:00:00:00 On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 229762 WFC3/UVI ACCUM UVIS2-C51 F606W FLASH=8.0, CR-SPLIT=NO 1 192 S (384 POS TARG -.1582, S 2C-SUB S) 0.0289867; PATTERN 1 1 ------------------------------------------------------------------------------------------------------------------------------------ 2 229762 WFC3/UVI ACCUM UVIS2-C51 F814W FLASH=10.0, CR-SPLIT=NO 1 326 S (652 POS TARG -0.153256, S 2C-SUB S) -0.144537; PATTERN 1 2 ------------------------------------------------------------------------------------------------------------------------------------ 3 229762 WFC3/UVI ACCUM UVIS2-C51 F814W FLASH=10.0, CR-SPLIT=NO 1 326 S (652 POS TARG 0.0541835, S 2C-SUB S) 0.0385166; PATTERN 1 3 ------------------------------------------------------------------------------------------------------------------------------------ 4 229762 WFC3/UVI ACCUM UVIS2-C51 F606W FLASH=8.0, CR-SPLIT=NO 1 192 S (384 POS TARG 0.0494375, S 2C-SUB S) -0.145331; PATTERN 1 4 ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ 229762 1 WFC3/UVI ACCUM UVIS2-C5 F606W 1 none none none 1 N/A S 12C-SUB 229762 1 WFC3/UVI ACCUM UVIS2-C5 F606W 2 none none none 1 N/A S 12C-SUB 229762 2 WFC3/UVI ACCUM UVIS2-C5 F814W 1 none none none 1 N/A S 12C-SUB 229762 2 WFC3/UVI ACCUM UVIS2-C5 F814W 2 none none none 1 N/A S 12C-SUB 229762 3 WFC3/UVI ACCUM UVIS2-C5 F814W 1 none none none 1 N/A S 12C-SUB 229762 3 WFC3/UVI ACCUM UVIS2-C5 F814W 2 none none none 1 N/A S 12C-SUB 229762 4 WFC3/UVI ACCUM UVIS2-C5 F606W 1 none none none 1 N/A S 12C-SUB 229762 4 WFC3/UVI ACCUM UVIS2-C5 F606W 2 none none none 1 N/A S 12C-SUB 15233( 5) - 04-Jun-2018 16:51:32 - [ 9] Summary Form for Proposal 15233 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures UVIS2-C512C-SUB ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFC3/UVIS ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters CR-SPLIT=NO, FLASH=10.0, FLASH=12.0, FLASH=8.0 ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements AFTER 01 BY 10 H TO 20 H, AFTER 03 BY 3 D TO 4 D, BETWEEN 02-AUG-2018:00:00:00 AND 07-AUG-2018:00:00:00, BETWEEN 15-DEC-2017:00:00:00 AND 10-JAN-2018:00:00:00, PATTERN 1 1, PATTERN 1 2, PATTERN 1 3, PATTERN 1 4, POS TARG -.1582, 0.0289867, POS TARG -0.153256, -0.144537, POS TARG 0.0494375, -0.145331, POS TARG 0.0541835, 0.0385166, SCHED 30% ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F438W, F606W, F814W ------------------------------------------------------------------------------------------------------------------------------------ Target Names 229762 ------------------------------------------------------------------------------------------------------------------------------------