9059( 13) - 12/21/04 12:27 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 9059 Version: 13 Check-in Date: 21-Dec-2004 17:24:20 1.Proposal Title: UV/Visible Spectroscopy of Asteroid 762 Pulcova and its Newly-discovered Moon ------------------------------------------------------------------------------------ 2. Proposal For 3. Cycle 4. Parallel Pointing Tolerance GO 10 ------------------------------------------------------------------------------------ 5. Investigators Contact? PI: Dr. William J. Merline Southwest Research Institute CoI: Dr. Clark R. Chapman Southwest Research Institute N CoI: Dr. Christophe Dumas Jet Propulsion Laboratory N CoI: Dr. Laird Close University of Arizona N CoI: Dr. Daniel D. Durda Southwest Research Institute N CoI: Dr. S. Alan Stern Southwest Research Institute N CoI: Dr. Schelte J. Bus University of Hawaii N CoI: Dr. Richard P. Binzel Massachusetts Institute of Technology N ------------------------------------------------------------------------------------ 6. Abstract We propose to acquire separte, comparative, and simultaneous spectra of asteroid 762 Pulcova and its satellite. We will compare our results with those we obtain[ed] in a program approved in cycle 9 for 45 Eugenia and its moon. We discovered both of these moons using ground-based adaptive optics -- Eugenia in 1998, but Pulcova only in the last year. We can now compare two systems that both have primaries of the relatively uncommon F-like spectral class. We will use the high-spatial-resolution and UV- capabilities of STIS to obtain medium-resolution spectra over the range 2900-10300 Anstrom, using only two grating settings, on a single HST orbit. We will determine whether the surface compositions are similar or different in the parent-satellite pair and test hypotheses concerning satellite production mechanisms. Our fits to the orbits yield a surprisingly low density for Eugenia of 1.2 g/cm^3, but that of Pulcova is 50% higher. F-type spectra are similar to the common C-types, but differ by the lack of a UV-band or UV-dropoff and by subtle, but measurable differences in the spectral slope. Both the UV-region and the existence of subtle absorption features in the near-IR (approx 9000 Anstroms) are diagnostic of the specific differences between F-, C-, and (Bus') X-class. HST is required because the ground- based adaptive optics is not available in the UV and cannot yet provide adequate resolution in the visible. ------------------------------------------------------------------------------------ 9059( 13) - 12/21/04 12:27 - [ 2] Observations Description ------------------------ This is a modification to the original proposal to use ACS/HRC instead of STIS. In this version, 4 exposures for dither and CR-split are taken in each of three modes: broadband imaging (3s per), prism spectroscopic (300s per), and grism spectroscopic (300s). The images substitute for the usual pre-spectroscopic image and are specified explicitly to optimize for CR/bad pixel rejection and appropriate dynamic range. The pair of spectroscopic modes are ideal for the critical distinguishing features in the near-UV and near-IR. Real Time Justification ----------------------- Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ 9059( 13) - 12/21/04 12:27 - [ 3] TARGET LIST Solar System Targets ------------------------------------------------------------------------------------------------------------------------------------ TARGET NUMBER: 1 | TARGET NAME: MP762-PULCOVA ------------------------------------------------------------------------------------------------------------------------------------ TARGET DESCRIPTION: ASTEROID Pulcova ------------------------------------------------------------------------------------------------------------------------------------ TARGET POSITION LEVEL 1 | TARGET POSITION LEVEL 2 | TYPE=ASTEROID,A=3.1591679,E=0.0965021,I= | 13.04942,O=306.03842,W=188.09717,M=332.0 | 8682,EPOCH=30-Jan-2005,EQUINOX=J2000 | | ------------------------------------------------------------------------------------------------------------------------------------ TARGET POSITION LEVEL 3 | WINDOWS | | ------------------------------------------------------------------------------------------------------------------------------------ DATA | COMMENTS | V = 12.2+/-0.3 | satellite is 4 mag fainter | | Acquisition Uncertainty: 1.0 " | ------------------------------------------------------------------------------------------------------------------------------------ 9059( 13) - 12/21/04 12:27 - [ 4] Visit: 01 Visit Priority: Visit Requirements: PCS MODE FINE; SCHED 100%; ORIENT 73.0D TO 84.5 D; BETWEEN 08-JAN- 2005:12:00:00 AND 20-JAN-2005:12:00:00; Period 2.072 D AND ZERO-PHASE JD2453378.6307; VISIBILITY INTERVAL 51 M 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 MP762-PULCO ACS/HRC ACCUM HRC F550M GAIN=4,CR-SPLIT=NO 1 5 S POS TARG 0, 0; PHASE 0.42 VA TO 0.58; SEQ 1-16 NON-INT ------------------------------------------------------------------------------------------------------------------------------------ 2 MP762-PULCO ACS/HRC ACCUM HRC F330W GAIN=4,CR-SPLIT=NO 1 40 S SAME POS AS 1 VA ------------------------------------------------------------------------------------------------------------------------------------ 3 MP762-PULCO ACS/HRC ACCUM HRC PR200L GAIN=4,CR-SPLIT=5,AUTOIMAGE=NO 1 45 S SAME POS AS 1 VA Comments: AUTOIMAGE=NO because explicitly taking an equivalent image with appropriate exposure time for both primary and secondary. ------------------------------------------------------------------------------------------------------------------------------------ 4 MP762-PULCO ACS/HRC ACCUM HRC PR200L GAIN=4,CR-SPLIT=4,AUTOIMAGE=NO 1 36 S POS TARG 0, 0.945 VA ------------------------------------------------------------------------------------------------------------------------------------ 5 MP762-PULCO ACS/HRC ACCUM HRC PR200L GAIN=4,CR-SPLIT=NO, 1 2 S SAME POS AS 4 VA AUTOIMAGE=NO Comments: Intentional short exposure to extract more information from red end of primary's spectrum which may be saturated in other spectra. ------------------------------------------------------------------------------------------------------------------------------------ 6 MP762-PULCO ACS/HRC ACCUM HRC PR200L GAIN=4,AUTOIMAGE=NO, 1 36 S SAME POS AS 4 VA CR-SPLIT=NO Comments: Intentional saturation on primary at red end allows deeper on secondary toward blue end. ------------------------------------------------------------------------------------------------------------------------------------ 7 MP762-PULCO ACS/HRC ACCUM HRC F330W GAIN=4,CR-SPLIT=NO 1 40 S SAME POS AS 4 VA ------------------------------------------------------------------------------------------------------------------------------------ 8 MP762-PULCO ACS/HRC ACCUM HRC F502N CR-SPLIT=NO,GAIN=4 1 60 S SAME POS AS 4 VA ------------------------------------------------------------------------------------------------------------------------------------ 9 MP762-PULCO ACS/HRC ACCUM HRC G800L GAIN=4,CR-SPLIT=NO, 1 360 S SAME POS AS 4 VA AUTOIMAGE=NO Comments: Intentional saturation on primary allows deeper on secondary in lower efficiency region. 360s allows simultaneous buffer dump. ------------------------------------------------------------------------------------------------------------------------------------ 9059( 13) - 12/21/04 12:27 - [ 5] Exposures ----------------------------------------------------------------------------------------------------------------------------------- Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| | Requirements ----------------------------------------------------------------------------------------------------------------------------------- 10 MP762-PULCO ACS/HRC ACCUM HRC G800L GAIN=4,CR-SPLIT=NO, 1 120 S SAME POS AS 4 VA AUTOIMAGE=NO ------------------------------------------------------------------------------------------------------------------------------------ 11 MP762-PULCO ACS/HRC ACCUM HRC G800L GAIN=4,CR-SPLIT=NO, 1 120 S SAME POS AS 1 VA AUTOIMAGE=NO ------------------------------------------------------------------------------------------------------------------------------------ 12 MP762-PULCO ACS/HRC ACCUM HRC G800L GAIN=4,CR-SPLIT=NO, 1 30 S SAME POS AS 1 VA AUTOIMAGE=NO Comments: Intentionally short in case primary red spectra are unexpectedly saturated. ------------------------------------------------------------------------------------------------------------------------------------ 13 MP762-PULCO ACS/HRC ACCUM HRC F606W GAIN=4,CR-SPLIT=NO 1 2 S SAME POS AS 1 VA ------------------------------------------------------------------------------------------------------------------------------------ 14 MP762-PULCO ACS/HRC ACCUM HRC F435W GAIN=4,CR-SPLIT=NO 1 5 S SAME POS AS 1 VA ------------------------------------------------------------------------------------------------------------------------------------ 15 MP762-PULCO ACS/HRC ACCUM HRC F344N GAIN=4,CR-SPLIT=NO 1 120 S SAME POS AS 1; EXPAND VA ------------------------------------------------------------------------------------------------------------------------------------ 16 MP762-PULCO ACS/HRC ACCUM HRC F550M GAIN=4,CR-SPLIT=NO 1 5 S SAME POS AS 1 VA ------------------------------------------------------------------------------------------------------------------------------------ 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 | ------------------------------------------------------------------------------------------------------------------------------------ MP762-PULCOVA 1 ACS/HRC ACCUM HRC F550M none none none none 1 N/A MP762-PULCOVA 2 ACS/HRC ACCUM HRC F330W none none none none 1 N/A MP762-PULCOVA 3 ACS/HRC ACCUM HRC PR200L none none none 1 1 N/A MP762-PULCOVA 3 ACS/HRC ACCUM HRC PR200L none none none 2 1 N/A MP762-PULCOVA 3 ACS/HRC ACCUM HRC PR200L none none none 3 1 N/A MP762-PULCOVA 3 ACS/HRC ACCUM HRC PR200L none none none 4 1 N/A MP762-PULCOVA 3 ACS/HRC ACCUM HRC PR200L none none none 5 1 N/A MP762-PULCOVA 4 ACS/HRC ACCUM HRC PR200L none none none 1 1 N/A MP762-PULCOVA 4 ACS/HRC ACCUM HRC PR200L none none none 2 1 N/A MP762-PULCOVA 4 ACS/HRC ACCUM HRC PR200L none none none 3 1 N/A MP762-PULCOVA 4 ACS/HRC ACCUM HRC PR200L none none none 4 1 N/A MP762-PULCOVA 5 ACS/HRC ACCUM HRC PR200L none none none none 1 N/A MP762-PULCOVA 6 ACS/HRC ACCUM HRC PR200L none none none none 1 N/A MP762-PULCOVA 7 ACS/HRC ACCUM HRC F330W none none none none 1 N/A MP762-PULCOVA 8 ACS/HRC ACCUM HRC F502N none none none none 1 N/A MP762-PULCOVA 9 ACS/HRC ACCUM HRC G800L none none none none 1 N/A MP762-PULCOVA 10 ACS/HRC ACCUM HRC G800L none none none none 1 N/A MP762-PULCOVA 11 ACS/HRC ACCUM HRC G800L none none none none 1 N/A MP762-PULCOVA 12 ACS/HRC ACCUM HRC G800L none none none none 1 N/A 9059( 13) - 12/21/04 12:27 - [ 6] 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 | ------------------------------------------------------------------------------------------------------------------------------------ MP762-PULCOVA 13 ACS/HRC ACCUM HRC F606W none none none none 1 N/A MP762-PULCOVA 14 ACS/HRC ACCUM HRC F435W none none none none 1 N/A MP762-PULCOVA 15 ACS/HRC ACCUM HRC F344N none none none none 1 N/A MP762-PULCOVA 16 ACS/HRC ACCUM HRC F550M none none none none 1 N/A 9059( 13) - 12/21/04 12:27 - [ 7] Summary Form for Proposal 9059 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures HRC ------------------------------------------------------------------------------------------------------------------------------------ Configurations ACS/HRC ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters GAIN=4 CR-SPLIT=NO CR-SPLIT=5 AUTOIMAGE=NO CR-SPLIT=4 ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements PCS MODE FINE; SCHED 100%; ORIENT 73.0D TO 84.5 D; BETWEEN 08-JAN-2005 12 00 00 AND 20-JAN-2005 12 00 00; Period 2.072 D AND ZERO-PHASE JD2453378.6307; VISIBILITY INTERVAL 51 M POS TARG 0, 0; PHASE 0.42 TO 0.58; SEQ 1-16 NON-INT SAME POS AS 1 POS TARG 0, 0.945 SAME POS AS 4 SAME POS AS 1; EXPAND ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F550M F330W PR200L F502N G800L F606W F435W F344N ------------------------------------------------------------------------------------------------------------------------------------ Target Names MP762-PULCOVA ------------------------------------------------------------------------------------------------------------------------------------