10469( 1) - 03/24/05 07:55 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 10469 Version: 1 Check-in Date: 24-Mar-2005 12:54:36 1.Proposal Title: The Gas Environment of Comet 9P/Tempel 1 During the Deep Impact Encounter ------------------------------------------------------------------------------------ 2. Proposal For 3. Cycle 4. Parallel Pointing Tolerance GO 13 ------------------------------------------------------------------------------------ 5. Investigators Contact? PI: Dr. Paul D. Feldman The Johns Hopkins University CoI: Dr. Michael F. A'Hearn University of Maryland N CoI: Dr. Harold A. Weaver The Johns Hopkins University Applied N Physics Laboratory CoI: Dr. Michael J. Belton Belton Space Exploration Initiatives N CoI: Dr. Karen J. Meech University of Hawaii N ------------------------------------------------------------------------------------ 6. Abstract We propose a series of observations of the periodic comet 9P/Tempel 1 in conjunction with NASA's Deep Impact mission. This mission is a spacecraft that will release a 360 kg impactor into the nucleus of the comet on July 4, 2005. Our primary objective is to study the generation and evolution of the gaseous coma resulting from this impact. To this end we plan to obtain ultraviolet spectra with STIS before, during, and following the impact. As a secondary objective we will obtain wide-band images of the visual outburst resulting from the impact. We also plan to use the high resolution capability of the ACS/HRC, in conjunction with the camera on board the spacecraft, two weeks prior to impact, to determine the spatial orientation of active jets emanating from the comet's nucleus and to assess the potential hazards of these jets to the spacecraft. ------------------------------------------------------------------------------------ 10469( 1) - 03/24/05 07:55 - [ 2] Observations Description ------------------------ The primary objective of this program will be to observe comet 9P/Tempel 1 at the time of the Deep Impact mission delivery of the impactor to the surface of the comet. This event occurs just after the beginning of cycle 14, but prior to this event, around June 20, 2005, we will use four orbits to image the comet with ACS/HRC in order to obtain stereographic images of jet activity, at comparable spatial resolution, in coordination with simultaneous on-board imaging. At this time, the comet will have a heliocentric distance of 1.514 AU, and a geocentric distance of 0.826 AU. Based on previous apparitions, the total V magnitude will be about 10 while the nuclear V magnitude, based on an estimated effective radius of 2.5-3.0 km, will be between 17 and 18. For this purpose optimum sensitivity is obtained with the use of the broad band F606W filter. The nucleus will be photometrically, though not spatially, resolved from the surrounding coma and jet structures. From the ACS Exposure Time Calculator, for V=17 the full well of the CCD will be reached in an exposure time of 270 seconds. While it is not possible to assess the brightness of any jets that may be present, we expect that any jets or coma structure with surface brightness 1.e-4 per pixel that of the nucleus will easily be detectable above the sky background and detector dark levels. In order to optimize the search for jet structures, the four orbits will be equally spaced over a single rotation period of the comet, currently believed to be 42 hours. However, it is possible that the true period is one-half of that or 21 hours. Coming observations may resolve this issue. The spacing of the orbits will be revisited a few months prior to the scheduling of this program. Real Time Justification ----------------------- As described above, these observations are being coordinated with and need to be made at the time of the active phase of the Deep Impact mission, end of June 2005 through early July 2005 (note the cycle 13 boundary is crossed during this time). Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ 10469( 1) - 03/24/05 07:55 - [ 3] TARGET LIST Solar System Targets ------------------------------------------------------------------------------------------------------------------------------------ TARGET NUMBER: 1 | TARGET NAME: COMET-TEMPEL-1 ------------------------------------------------------------------------------------------------------------------------------------ TARGET DESCRIPTION: COMET COMET 9P/TEMPEL 1 ------------------------------------------------------------------------------------------------------------------------------------ TARGET POSITION LEVEL 1 | TARGET POSITION LEVEL 2 | TYPE=COMET,Q=1.505258900047598,E=0.51759 | 6959921202,I=10.53089403258074,O=68.9637 | 0938666549,W=178.8714698110478,T = 05- | Jul- | 2005:08:51:29.0,EQUINOX=J2000,EPOCH=01- | May-2004,A1=9.138764E-11,A2=1.761489E- | 11,A3=0.0 | | ------------------------------------------------------------------------------------------------------------------------------------ TARGET POSITION LEVEL 3 | WINDOWS | | ------------------------------------------------------------------------------------------------------------------------------------ DATA | COMMENTS | V = 17.0+/-1.0 | Comet 9P/Tempel 1 is the target of | the Deep Impact mission. The | elements given below are from | JPL#K058/3. | ------------------------------------------------------------------------------------------------------------------------------------ 10469( 1) - 03/24/05 07:55 - [ 4] Patterns ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 1 Primary_Pattern Secondary_Pattern Pattern_Type ACS-HRC-DITHER-LINE Pattern_Purpose DITHER Number_Of_Points 3 Point_Spacing 0.077 Line_Spacing Coordinate_Frame POS-TARG Pattern_Orient 31.1 Angle_Between_Sides Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ 10469( 1) - 03/24/05 07:55 - [ 5] Visit: 01 Visit Priority: Visit Requirements: PCS MODE FINE; BETWEEN 19-JUN-2005:00:00:00 AND 22-JUN-2005:00:00:00; SEQ 01, 02, 03, 04 WITHIN 42 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| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 COMET-TEMPE ACS/HRC ACCUM HRC F606W CR-SPLIT=NO,PAREXP=NONE 1 60 S PATTERN 1 1-2 L-1 see below ------------------------------------------------------------------------------------------------------------------------------------ 2 COMET-TEMPE ACS/HRC ACCUM HRC F606W CR-SPLIT=NO,PAREXP=NONE 1 735 S L-1 see below ------------------------------------------------------------------------------------------------------------------------------------ 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 | ------------------------------------------------------------------------------------------------------------------------------------ COMET-TEMPEL-1 1 ACS/HRC ACCUM HRC F606W 1 none none none 1 63.0 S COMET-TEMPEL-1 1 ACS/HRC ACCUM HRC F606W 2 none none none 1 63.0 S COMET-TEMPEL-1 1 ACS/HRC ACCUM HRC F606W 3 none none none 1 63.0 S COMET-TEMPEL-1 2 ACS/HRC ACCUM HRC F606W 1 none none none 1 743.0 S COMET-TEMPEL-1 2 ACS/HRC ACCUM HRC F606W 2 none none none 1 743.0 S COMET-TEMPEL-1 2 ACS/HRC ACCUM HRC F606W 3 none none none 1 743.0 S 10469( 1) - 03/24/05 07:55 - [ 6] Visit: 02 Visit Priority: Visit Requirements: PCS MODE FINE; AFTER 01 BY 6.9 Orbits TO 7.1 Orbits; SEQ 01, 02, 03, 04 WITHIN 42 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| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 COMET-TEMPE ACS/HRC ACCUM HRC F606W CR-SPLIT=NO,PAREXP=NONE 1 60 S PATTERN 1 1-2 L-1 see below ------------------------------------------------------------------------------------------------------------------------------------ 2 COMET-TEMPE ACS/HRC ACCUM HRC F606W CR-SPLIT=NO,PAREXP=NONE 1 735 S L-1 see below ------------------------------------------------------------------------------------------------------------------------------------ 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 | ------------------------------------------------------------------------------------------------------------------------------------ COMET-TEMPEL-1 1 ACS/HRC ACCUM HRC F606W 1 none none none 1 63.0 S COMET-TEMPEL-1 1 ACS/HRC ACCUM HRC F606W 2 none none none 1 63.0 S COMET-TEMPEL-1 1 ACS/HRC ACCUM HRC F606W 3 none none none 1 63.0 S COMET-TEMPEL-1 2 ACS/HRC ACCUM HRC F606W 1 none none none 1 743.0 S COMET-TEMPEL-1 2 ACS/HRC ACCUM HRC F606W 2 none none none 1 743.0 S COMET-TEMPEL-1 2 ACS/HRC ACCUM HRC F606W 3 none none none 1 743.0 S 10469( 1) - 03/24/05 07:55 - [ 7] Visit: 03 Visit Priority: Visit Requirements: PCS MODE FINE; AFTER 02 BY 7.9 Orbits TO 8.1 Orbits; SEQ 01, 02, 03, 04 WITHIN 42 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| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 COMET-TEMPE ACS/HRC ACCUM HRC F606W CR-SPLIT=NO,PAREXP=NONE 1 60 S PATTERN 1 1-2 L-1 see below ------------------------------------------------------------------------------------------------------------------------------------ 2 COMET-TEMPE ACS/HRC ACCUM HRC F606W CR-SPLIT=NO,PAREXP=NONE 1 735 S L-1 see below ------------------------------------------------------------------------------------------------------------------------------------ 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 | ------------------------------------------------------------------------------------------------------------------------------------ COMET-TEMPEL-1 1 ACS/HRC ACCUM HRC F606W 1 none none none 1 63.0 S COMET-TEMPEL-1 1 ACS/HRC ACCUM HRC F606W 2 none none none 1 63.0 S COMET-TEMPEL-1 1 ACS/HRC ACCUM HRC F606W 3 none none none 1 63.0 S COMET-TEMPEL-1 2 ACS/HRC ACCUM HRC F606W 1 none none none 1 743.0 S COMET-TEMPEL-1 2 ACS/HRC ACCUM HRC F606W 2 none none none 1 743.0 S COMET-TEMPEL-1 2 ACS/HRC ACCUM HRC F606W 3 none none none 1 743.0 S 10469( 1) - 03/24/05 07:55 - [ 8] Visit: 04 Visit Priority: Visit Requirements: PCS MODE FINE; AFTER 03 BY 6.9 Orbits TO 7.1 Orbits; SEQ 01, 02, 03, 04 WITHIN 42 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| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 COMET-TEMPE ACS/HRC ACCUM HRC F606W CR-SPLIT=NO,PAREXP=NONE 1 60 S PATTERN 1 1-2 L-1 see below ------------------------------------------------------------------------------------------------------------------------------------ 2 COMET-TEMPE ACS/HRC ACCUM HRC F606W CR-SPLIT=NO,PAREXP=NONE 1 735 S L-1 see below ------------------------------------------------------------------------------------------------------------------------------------ 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 | ------------------------------------------------------------------------------------------------------------------------------------ COMET-TEMPEL-1 1 ACS/HRC ACCUM HRC F606W 1 none none none 1 63.0 S COMET-TEMPEL-1 1 ACS/HRC ACCUM HRC F606W 2 none none none 1 63.0 S COMET-TEMPEL-1 1 ACS/HRC ACCUM HRC F606W 3 none none none 1 63.0 S COMET-TEMPEL-1 2 ACS/HRC ACCUM HRC F606W 1 none none none 1 743.0 S COMET-TEMPEL-1 2 ACS/HRC ACCUM HRC F606W 2 none none none 1 743.0 S COMET-TEMPEL-1 2 ACS/HRC ACCUM HRC F606W 3 none none none 1 743.0 S 10469( 1) - 03/24/05 07:55 - [ 9] Summary Form for Proposal 10469 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures HRC ------------------------------------------------------------------------------------------------------------------------------------ Configurations ACS/HRC ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters CR-SPLIT=NO PAREXP=NONE ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements PCS MODE FINE; BETWEEN 19-JUN-2005 00 00 00 AND 22-JUN-2005 00 00 00; SEQ 01, 02, 03, 04 WITHIN 42 H PATTERN 1 1-2 PCS MODE FINE; AFTER 01 BY 6.9 Orbits TO 7.1 Orbits; SEQ 01, 02, 03, 04 WITHIN 42 H PCS MODE FINE; AFTER 02 BY 7.9 Orbits TO 8.1 Orbits; SEQ 01, 02, 03, 04 WITHIN 42 H PCS MODE FINE; AFTER 03 BY 6.9 Orbits TO 7.1 Orbits; SEQ 01, 02, 03, 04 WITHIN 42 H ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F606W ------------------------------------------------------------------------------------------------------------------------------------ Target Names COMET-TEMPEL-1 ------------------------------------------------------------------------------------------------------------------------------------