10759( 11) - 10/26/05 11:15 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 10759 Version: 11 Check-in Time: 26-Oct-2005 15:14:57 Title Direct measurement of the size of 2003 UB313 ------------------------------------------------------------------------------------ Type Cycle Parallel Pointing Tolerance GO/DD 14 ------------------------------------------------------------------------------------ Investigators Contact? PI: Dr. Michael E. Brown California Institute of Technology CoI: Dr. Chadwick A. Trujillo Gemini Observatory, Northern Operations N CoI: Dr. David L. Rabinowitz Yale University N ------------------------------------------------------------------------------------ Abstract We propose observations ito directly measure the size of the newly discovered object 2003 UB313. The observations are identical to those used to successfully measure the size of the minor planet (50000) Quaoar and have a high chance of obtaining the first concrete size measurement of this object. Even for an absurdly high albedo of 96% this object is larger than Pluto. For more reasonable albedos the object could be as large as 1.5 times Pluto. At a distance of 97 AU a Pluto-sized object would subtend 32 milliarcseconds, well within our previously estimate limit of 20 milliarcseconds for accurate measurement. For a more reasonable Pluto-like albedo the object would subtend 42 millarcseconds, essentially identical to Quaoar, which was successfully resolved by our team several years ago. The direct measurement will be the cornerstone of the size measurement of this object, which will also include radiometric observations from Spitzer, IRAM, and the CSO. We anticipate a single thorough analysis using all available means to get the best true size measurement possible. ------------------------------------------------------------------------------------ Observations Description ------------------------ TBD Real Time Justification ----------------------- Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ 10759( 11) - 10/26/05 11:15 - [ 2] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 APPULSE- STAR, UNDESIGNATED RA=01H35M37.6300S +/- 0.5", J2000 V = 19.52+/-0.3 STAR-1 DEC=-05D39'57.80" +/- 0.5" Coordinate Source: PPM_STAR_CATALOGUE Comments: Appulse star for the measurement of the size of the Kuiper belt object. The star should be centered in the field, the KBO will also be in the field if observed during the constrained times 10759( 11) - 10/26/05 11:15 - [ 3] Patterns ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 1 Primary_Pattern Secondary_Pattern Pattern_Type ACS-HRC-DITHER-BOX Pattern_Purpose DITHER Number_Of_Points 4 Point_Spacing 0.15 Line_Spacing 0.098 Coordinate_Frame POS-TARG Pattern_Orient 19.89 Angle_Between_Sides 63.5 Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ 10759( 11) - 10/26/05 11:15 - [ 4] Visit: 01 Visit Priority: Visit Requirements: BETWEEN 09-DEC-2005:06:00:00 AND 09-DEC-2005:19:00:00 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| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 APPULSE-STA ACS/HRC ACCUM HRC F435W CR-SPLIT=4 1 476 S PATTERN 1 1 R-1 ------------------------------------------------------------------------------------------------------------------------------------ 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 | ------------------------------------------------------------------------------------------------------------------------------------ APPULSE-STAR-1 1 ACS/HRC ACCUM HRC F435W 1 none none 1 1 N/A APPULSE-STAR-1 1 ACS/HRC ACCUM HRC F435W 1 none none 2 1 N/A APPULSE-STAR-1 1 ACS/HRC ACCUM HRC F435W 1 none none 3 1 N/A APPULSE-STAR-1 1 ACS/HRC ACCUM HRC F435W 1 none none 4 1 N/A APPULSE-STAR-1 1 ACS/HRC ACCUM HRC F435W 2 none none 1 1 N/A APPULSE-STAR-1 1 ACS/HRC ACCUM HRC F435W 2 none none 2 1 N/A APPULSE-STAR-1 1 ACS/HRC ACCUM HRC F435W 2 none none 3 1 N/A APPULSE-STAR-1 1 ACS/HRC ACCUM HRC F435W 2 none none 4 1 N/A APPULSE-STAR-1 1 ACS/HRC ACCUM HRC F435W 3 none none 1 1 N/A APPULSE-STAR-1 1 ACS/HRC ACCUM HRC F435W 3 none none 2 1 N/A APPULSE-STAR-1 1 ACS/HRC ACCUM HRC F435W 3 none none 3 1 N/A APPULSE-STAR-1 1 ACS/HRC ACCUM HRC F435W 3 none none 4 1 N/A APPULSE-STAR-1 1 ACS/HRC ACCUM HRC F435W 4 none none 1 1 N/A APPULSE-STAR-1 1 ACS/HRC ACCUM HRC F435W 4 none none 2 1 N/A APPULSE-STAR-1 1 ACS/HRC ACCUM HRC F435W 4 none none 3 1 N/A APPULSE-STAR-1 1 ACS/HRC ACCUM HRC F435W 4 none none 4 1 N/A 10759( 11) - 10/26/05 11:15 - [ 5] Visit: 02 Visit Priority: Visit Requirements: BETWEEN 10-DEC-2005:00:00:00 AND 10-DEC-2005:12:00:00 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| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 APPULSE-STA ACS/HRC ACCUM HRC F435W CR-SPLIT=3 1 399 S PATTERN 1 1 R-1 ------------------------------------------------------------------------------------------------------------------------------------ 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 | ------------------------------------------------------------------------------------------------------------------------------------ APPULSE-STAR-1 1 ACS/HRC ACCUM HRC F435W 1 none none 1 1 N/A APPULSE-STAR-1 1 ACS/HRC ACCUM HRC F435W 1 none none 2 1 N/A APPULSE-STAR-1 1 ACS/HRC ACCUM HRC F435W 1 none none 3 1 N/A APPULSE-STAR-1 1 ACS/HRC ACCUM HRC F435W 2 none none 1 1 N/A APPULSE-STAR-1 1 ACS/HRC ACCUM HRC F435W 2 none none 2 1 N/A APPULSE-STAR-1 1 ACS/HRC ACCUM HRC F435W 2 none none 3 1 N/A APPULSE-STAR-1 1 ACS/HRC ACCUM HRC F435W 3 none none 1 1 N/A APPULSE-STAR-1 1 ACS/HRC ACCUM HRC F435W 3 none none 2 1 N/A APPULSE-STAR-1 1 ACS/HRC ACCUM HRC F435W 3 none none 3 1 N/A APPULSE-STAR-1 1 ACS/HRC ACCUM HRC F435W 4 none none 1 1 N/A APPULSE-STAR-1 1 ACS/HRC ACCUM HRC F435W 4 none none 2 1 N/A APPULSE-STAR-1 1 ACS/HRC ACCUM HRC F435W 4 none none 3 1 N/A 10759( 11) - 10/26/05 11:15 - [ 6] Summary Form for Proposal 10759 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures HRC ------------------------------------------------------------------------------------------------------------------------------------ Configurations ACS/HRC ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters CR-SPLIT=4 CR-SPLIT=3 ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements BETWEEN 09-DEC-2005 06 00 00 AND 09-DEC-2005 19 00 00; PATTERN 1 1; BETWEEN 10-DEC-2005 00 00 00 AND 10-DEC-2005 12 00 00; ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F435W ------------------------------------------------------------------------------------------------------------------------------------ Target Names APPULSE-STAR-1 ------------------------------------------------------------------------------------------------------------------------------------