Page 1 PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID 4193c Report Date: 09-May-96:19:24 Version: ********** Check-in Date: ********** 1.Proposal Title: OPPORTUNITY OCCULTATIONS BY SMALL BODIES - CONT OF 1079 ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Proposal Type 5. Continuation ID SOLAR SYSTEM GTO/HSP Target of Oppt. 1079 Sub Category ------------------------------------------------------------------------------------ 6. Principal Investigator Institution Country Telephone Robert C. Bless WISCONSIN, UNIVERSITY OF USA (608)262-1715 ------------------------------------------------------------------------------------ 7. Abstract Although an occultation by any specific comet, asteroid, satellite, or Pluto is unlikely to be observable from the ST, the scientific return from such an event would be great because of the superior signal-to-noise ratio achievable with the ST for occultation observations. We propose to observe occultations by these bodies with the ST, as the opportunites arise, to probe their atmospheres, determine their sizes and achieve other goals. With such diverse possibilities, one must examine each opportunity as it occurs and formulate an observing strategy to fit that particular case. Revision History: New targets added, 4/24/92, asb. ------------------------------------------------------------------------------------ 8. Scientific Key Words: COMET, ASTEROID, SATELLITE, PLUTO, OCCULTATION ------------------------------------------------------------------------------------ 9. Est obs time (hours) pri: 1.75 par: 0 10. Num targs pri: 7 par: 0 ------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------ 12. Special sched req: Time Critical obs. ------------------------------------------------------------------------------------ Page 2 I. GENERAL FORM Proposal 4193c PI: Robert C. Bless Proposal Title: OPPORTUNITY OCCULTATIONS BY SMALL BODIES - CONT OF 1079 ------------------------------------------------------------------------------------ 1. Proposers: Proposers Institution Country ESA ------------------------------------------------------------------------------------ Edward L. Robinson TEXAS, UNIVERSITY OF USA Robert C. Bless WISCONSIN, UNIVERSITY OF USA G. W. Van Citters NATIONAL SCIENCE FOUNDATION USA Joseph F. Dolan NASA, GODDARD SPACE FLIGHT USA CENTER Richard L. White SPACE TELESCOPE SCIENCE USA INSTITUTE James L. Elliot MASSACHUSETTS INSTITUTE OF USA TECHNOLOGY ------------------------------------------------------------------------------------ 3. Description of proposed observations. We plan to identify those occultations of sufficient signal-to-noise ratio to achieve the goals outlined in Section 2. Each observation will require (i) onboard acquisition to verify the guide stars; (ii) a scan of about ten arc- seconds along the track that the object will follow relative to the occulting body and (iii) a time series run on the object with whatever filter aperture combination that is chosen for the observation. For some occultations to be observed in the far UV, prior multi-filter photometry of the object will be necessary in order to determine the most appropriate filter to use for the occultation. For now, we shall assume that the calibration and observation time will average about 60 minutes per occultation observed. ------------------------------------------------------------------------------------ 4. Justification of need for HST observations. We can achieve a much better signal-to-noise ratio for the temperature profiles and other information than can be obtained for small body occultations than has been possible from the ground for the following reasons: (i) the greatly improved photometric stability of ST photometry, which will substantially reduce the errors in the numerical inversion of the data that is necessary to obtain the temperature profiles; (ii) our ability to reject background light from the occulting object (such as a comet ) by employing small focal plane apertures; and (iii) the absence of scintillation noise, which has strong components at frequencies comparable to the occultation timescale. ------------------------------------------------------------------------------------ 5. Description of special scheduling requirements. For bodies with possible atmospheres, tracking the occulted star will require a real time update, due to its complicated path caused by refraction in the occulting body's atmosphere and the uncertainties in predicting the ST orbit. ------------------------------------------------------------------------------------ 6. Description of special calibration exposures. For comets and the larger bodies (Titan, Triton, and Pluto) a prior scan over 10 arc-seconds is needed to map the scattered light field, which is needed for the data reduction. ------------------------------------------------------------------------------------ 7. Data reduction and analysis plans. Data will be reduced and analyzed at MIT with VAX 11-750 belonging to the planetary astronomy group. ------------------------------------------------------------------------------------ 10. Resources to be supplied by investigator's institution(s). TBD Page 3 ------------------------------------------------------------------------------------ 13. An observation of an occultation by a comet, asteroid, satellite, or Pluto would yield a variety of information. For example, we could gain further information about the atmospheres of Pluto and Triton, including knowledge of the composition and structure of their atmospheres. Also, the presence of possible material in the neighborhood of an asteroid could be obtained. Opportunity stellar occultations by small bodies are proposed to be observed with the HSP or FOS. ------------------------------------------------------------------------------------ 11. Address Information Name: ROBERT C. BLESS Category: PI Institution: UNIVERSITY OF WISCONSIN Address: DEPARTMENT OF ASTRONOMY 475 NORTH CHARTER STREET City: MADISON State: WI Zip Code: 53706 Country: USA Telephone: 608-262-1715 Telex (or e-mail): ------------------------------------------------------------------------------------ TARGET LIST a) Fixed Targets ID = 4193c [ 4] ------------------------------------------------------------------------------------------------------------------------------------ 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial |Acqui|FLX| Flux data No | Name | Description | Position |Eqnx | Vel. |Prblm|REF| | | | | | | | | ------------------------------------------------------------------------------------------------------------------------------------ 10 GSC6349- STAR TO BE OCCULTED PLATE-ID = 018A, J2000 BKG 1 B = 13.8 +/- 0.6 01493 TWICE BY TITAN. RA = 20H 58M 46.997S +/- CLOSE APPROACHES AT 7- 0.03", OCT-92:08:59, DEC = -18D 11' 32.52" +/- 0.05" Comments: SOLAR ELONG 117D ------------------------------------------------------------------------------------------------------------------------------------ 11 01493-OFFSET OFFSET TARGET FOR PLATE-ID = 018A, J2000 1 B = 15.5 +/- 0.6 GSC6349- GSC6349-01493 RA = 20H 58M 46.494S +/- 01494 0.06", DEC = -18D 10' 23.34" +/- 0.05" ------------------------------------------------------------------------------------------------------------------------------------ TARGET LIST b)Solar System Targets ID = 4193c [ 5] ------------------------------------------------------------------------------------------------------------------------------------ TARGET NUMBER: 12 | TARGET NAME: 01493-A-BACKGROUND ------------------------------------------------------------------------------------------------------------------------------------ TARGET DESCRIPTION: OFFSET TITAN ------------------------------------------------------------------------------------------------------------------------------------ TARGET POSITION LEVEL 1 | TARGET POSITION LEVEL 2 | STD = TITAN | TYPE = POS_ANGLE, | RAD = 25.5, | ANG = 98.8, | REF = NORTH | ------------------------------------------------------------------------------------------------------------------------------------ TARGET POSITION LEVEL 3 | WINDOWS | | ------------------------------------------------------------------------------------------------------------------------------------ REF | DATA | COMMENTS | | | | FOR USE IN A SCAN OF BACKGROUND | | LEVELS ALONG THE PATH OF THE | | OCCULTED STAR | ------------------------------------------------------------------------------------------------------------------------------------ TARGET NUMBER: 13 | TARGET NAME: 01493-B-BACKGROUND ------------------------------------------------------------------------------------------------------------------------------------ TARGET DESCRIPTION: OFFSET TITAN ------------------------------------------------------------------------------------------------------------------------------------ TARGET POSITION LEVEL 1 | TARGET POSITION LEVEL 2 | STD = TITAN | TYPE = POS_ANGLE, | RAD = 25.5, | ANG = 106.0, | REF = NORTH | ------------------------------------------------------------------------------------------------------------------------------------ TARGET POSITION LEVEL 3 | WINDOWS | | ------------------------------------------------------------------------------------------------------------------------------------ REF | DATA | COMMENTS | | | | FOR USE IN A SCAN OF BACKGROUND | | LEVELS ALONG THE PATH OF THE | | OCCULTED STAR | ------------------------------------------------------------------------------------------------------------------------------------ TARGET LIST b)Solar System Targets ID = 4193c [ 6] ------------------------------------------------------------------------------------------------------------------------------------ TARGET NUMBER: 14 | TARGET NAME: TITAN-CENTER ------------------------------------------------------------------------------------------------------------------------------------ TARGET DESCRIPTION: SATELLITE TITAN ------------------------------------------------------------------------------------------------------------------------------------ TARGET POSITION LEVEL 1 | TARGET POSITION LEVEL 2 | STD = TITAN, ACQ = 0.1 | | ------------------------------------------------------------------------------------------------------------------------------------ TARGET POSITION LEVEL 3 | WINDOWS | | ------------------------------------------------------------------------------------------------------------------------------------ REF | DATA | COMMENTS | | 1 |V = 8.3 +/- 0.5 | ACQUISITION TARGET FOR BACKGROUND | | SCANS | ------------------------------------------------------------------------------------------------------------------------------------ EXPOSURE LOGSHEET ID = 4193c [ 7] ------------------------------------------------------------------------------------------------------------------------------------ 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 |10 | 11 | 12 |13 |14| 15 ------------------------------------------------------------------------------------------------------------------------------------ Line | Seq | Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | S/N |Flx|Pr| Special Number | Name | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| |Rel. Time|Ref| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 4 DEFINE # HSP/ ACQ 1 1S 1 1 ONBRD- VIS ACQ ------------------------------------------------------------------------------------------------------------------------------------ 6 DEFINE # HSP/ SPLIT 1.0 F750W/ # 1 1S 1 1 SPATIAL SCAN BACK- PMT/ F320N SCAN VIS ------------------------------------------------------------------------------------------------------------------------------------ 7 DEFINE # HSP/ SPLIT 1.0 F750W/ # 1 1M 1 1 CRIT OBS OCC PMT/ F320N VIS ------------------------------------------------------------------------------------------------------------------------------------ 10 USE TITAN- X1 ONBOARD ACQ FOR ONBRD- CENTER 10.01 ACQ SEQ 10.00 - 10.01 NO GAP ------------------------------------------------------------------------------------------------------------------------------------ 10.01 USE 01493-A- SAMPLE- X200 SEQ 10.01 - 10.03 BACK- BACKGROUND TIME=0.05 GROUP 10.01 - SCAN PRECISION=HIGH 10.04 WITHIN 9H DATA-FORMAT=ALL CYCLE 2/10.00 - PMT-ANALOG=1000 10.28 VIS-ANALOG=10 ------------------------------------------------------------------------------------------------------------------------------------ 10.02 USE 01493-A- SAMPLE- X200 BACK- BACKGROUND TIME=0.05 SCAN PRECISION=HIGH DATA-FORMAT=ALL PMT-ANALOG=1000 VIS-ANALOG=10 ------------------------------------------------------------------------------------------------------------------------------------ 10.03 USE 01493-A- SAMPLE- X200 BACK- BACKGROUND TIME=0.05 SCAN PRECISION=HIGH DATA-FORMAT=ALL PMT-ANALOG=1000 VIS-ANALOG=10 ------------------------------------------------------------------------------------------------------------------------------------ 10.04 USE 01493- X120 ONBOARD ACQ FOR ONBRD- OFFSET 10.10 - 10.28 ACQ SEQ 10.04 - 10.10 NO GAP ------------------------------------------------------------------------------------------------------------------------------------ 10.1 USE OCC GSC6349- SAMPLE- X30 AT 7-OCT-92:08:45 01493 TIME=0.05 +/- 1M PRECISION=HIGH DATA-FORMAT=ALL PMT-ANALOG=1000 VIS-ANALOG=10 Comments: END EXPOSURE AT 7-OCT-92:09:14. ------------------------------------------------------------------------------------------------------------------------------------ EXPOSURE LOGSHEET ID = 4193c [ 8] ------------------------------------------------------------------------------------------------------------------------------------ 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 |10 | 11 | 12 |13 |14| 15 ------------------------------------------------------------------------------------------------------------------------------------ Line | Seq | Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | S/N |Flx|Pr| Special Number | Name | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| |Rel. Time|Ref| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 10.25 USE TITAN- X1 ONBOARD ACQ FOR ONBRD- CENTER 10.260 ACQ ------------------------------------------------------------------------------------------------------------------------------------ 10.26 USE 01493-A- SAMPLE- X200 SEQ 10.26 - 10.28 BACK- BACKGROUND TIME=0.05 GROUP 10.10 - SCAN PRECISION=HIGH 10.28 WITHIN 9H DATA-FORMAT=ALL PMT-ANALOG=1000 VIS-ANALOG=10 ------------------------------------------------------------------------------------------------------------------------------------ 10.27 USE 01493-A- SAMPLE- X200 BACK- BACKGROUND TIME=0.05 SCAN PRECISION=HIGH DATA-FORMAT=ALL PMT-ANALOG=1000 VIS-ANALOG=10 ------------------------------------------------------------------------------------------------------------------------------------ 10.28 USE 01493-A- SAMPLE- X200 BACK- BACKGROUND TIME=0.05 SCAN PRECISION=HIGH DATA-FORMAT=ALL PMT-ANALOG=1000 VIS-ANALOG=10 ------------------------------------------------------------------------------------------------------------------------------------ 11 USE TITAN- X1 ONBOARD ACQ FOR ONBRD- CENTER 11.01 ACQ SEQ 11.00 - 11.01 NO GAP ------------------------------------------------------------------------------------------------------------------------------------ 11.01 USE 01493-B- SAMPLE- X200 SEQ 11.01 - 11.03 BACK- BACKGROUND TIME=0.05 GROUP 11.01 - SCAN PRECISION=HIGH 11.04 WITHIN 9H DATA-FORMAT=ALL CYCLE 2/11.00 - PMT-ANALOG=1000 11.28 VIS-ANALOG=10 ------------------------------------------------------------------------------------------------------------------------------------ 11.02 USE 01493-B- SAMPLE- X200 BACK- BACKGROUND TIME=0.05 SCAN PRECISION=HIGH DATA-FORMAT=ALL PMT-ANALOG=1000 VIS-ANALOG=10 ------------------------------------------------------------------------------------------------------------------------------------ 11.03 USE 01493-B- SAMPLE- X200 BACK- BACKGROUND TIME=0.05 SCAN PRECISION=HIGH DATA-FORMAT=ALL PMT-ANALOG=1000 VIS-ANALOG=10 ------------------------------------------------------------------------------------------------------------------------------------ EXPOSURE LOGSHEET ID = 4193c [ 9] ------------------------------------------------------------------------------------------------------------------------------------ 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 |10 | 11 | 12 |13 |14| 15 ------------------------------------------------------------------------------------------------------------------------------------ Line | Seq | Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | S/N |Flx|Pr| Special Number | Name | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| |Rel. Time|Ref| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 11.04 USE 01493- X120 ONBOARD ACQ FOR ONBRD- OFFSET 11.10 - 11.28 ACQ SEQ 11.04 - 11.10 NO GAP ------------------------------------------------------------------------------------------------------------------------------------ 11.1 USE OCC GSC6349- SAMPLE- X30 AT 9-OCT-92:04:53 01493 TIME=0.05 +/- 1M PRECISION=HIGH DATA-FORMAT=ALL PMT-ANALOG=1000 VIS-ANALOG=10 Comments: END EXPOSURE AT 9-OCT-92:05:22. ------------------------------------------------------------------------------------------------------------------------------------ 11.25 USE TITAN- X1 ONBOARD ACQ FOR ONBRD- CENTER 11.260 ACQ ------------------------------------------------------------------------------------------------------------------------------------ 11.26 USE 01493-B- SAMPLE- X200 SEQ 11.26 - 11.28 BACK- BACKGROUND TIME=0.05 GROUP 11.10 - SCAN PRECISION=HIGH 11.28 WITHIN 9H DATA-FORMAT=ALL PMT-ANALOG=1000 VIS-ANALOG=10 ------------------------------------------------------------------------------------------------------------------------------------ 11.27 USE 01493-B- SAMPLE- X200 BACK- BACKGROUND TIME=0.05 SCAN PRECISION=HIGH DATA-FORMAT=ALL PMT-ANALOG=1000 VIS-ANALOG=10 ------------------------------------------------------------------------------------------------------------------------------------ 11.28 USE 01493-B- SAMPLE- X200 BACK- BACKGROUND TIME=0.05 SCAN PRECISION=HIGH DATA-FORMAT=ALL PMT-ANALOG=1000 VIS-ANALOG=10 ------------------------------------------------------------------------------------------------------------------------------------ Scan Paramters Form Proposal ID: 4193c [ 10] ------------------------------------------------------------------------------------------------------------------------------------ Data ID: 1 Exposure Logsheet lines: 10.01, 10.03, 10.26, FGS Scan: CONTINUOUS Dwell Only: dwell points/line: 0 Seconds per dwell: 0.00 Scan width (arc-secs): 0.0000 Scan length (arc-secs): 37.5000 Angle between sides (degrees) 90.00 Number of lines: 1 Scan rate (arc-sec/sec): 0.0750 PA of first scan line (degrees) 278.800 Scan frame (CEL or S/C): CEL Length Offset (arc-sec): 0. Width Offset (arc-sec): 0 ------------------------------------------------------------------------------------------------------------------------------------ Data ID: 2 Exposure Logsheet lines: 10.02, 10.27 FGS Scan: CONTINUOUS Dwell Only: dwell points/line: 0 Seconds per dwell: 0.00 Scan width (arc-secs): 2.0000 Scan length (arc-secs): 37.5000 Angle between sides (degrees) 90.00 Number of lines: 3 Scan rate (arc-sec/sec): 0.0750 PA of first scan line (degrees) 278.800 Scan frame (CEL or S/C): CEL Length Offset (arc-sec): 0. Width Offset (arc-sec): 1.0000 ------------------------------------------------------------------------------------------------------------------------------------ Data ID: 3 Exposure Logsheet lines: 11.01, 11.03, 11.26, FGS Scan: CONTINUOUS Dwell Only: dwell points/line: 0 Seconds per dwell: 0.00 Scan width (arc-secs): 0.0000 Scan length (arc-secs): 37.5000 Angle between sides (degrees) 90.00 Number of lines: 1 Scan rate (arc-sec/sec): 0.0750 PA of first scan line (degrees) 286.000 Scan frame (CEL or S/C): CEL Length Offset (arc-sec): 0. Width Offset (arc-sec): 0 ------------------------------------------------------------------------------------------------------------------------------------ Data ID: 4 Exposure Logsheet lines: 11.02, 11.27 FGS Scan: CONTINUOUS Dwell Only: dwell points/line: 0 Seconds per dwell: 0.00 Scan width (arc-secs): 2.0000 Scan length (arc-secs): 37.5000 Angle between sides (degrees) 90.00 Number of lines: 3 Scan rate (arc-sec/sec): 0.0750 PA of first scan line (degrees) 286.000 Scan frame (CEL or S/C): CEL Length Offset (arc-sec): 0. Width Offset (arc-sec): 1.0000 ------------------------------------------------------------------------------------------------------------------------------------ Summary Form for Proposal 4193c [ 11] Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations HSP/VIS HSP/PMT/VIS ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACQ SPLIT ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters SAMPLE-TIME PRECISION DATA-FORMAT PMT-ANALOG VIS-ANALOG ------------------------------------------------------------------------------------------------------------------------------------ Proposal for GTO/HSP ------------------------------------------------------------------------------------------------------------------------------------ S/C Hours 1.75 ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category SOLAR SYSTEM ------------------------------------------------------------------------------------------------------------------------------------ Scientific Sub-category ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements SPATIAL SCAN; CRIT OBS; ONBOARD ACQ FOR 10.01; SEQ 10.00 - 10.01 NO GAP; SEQ 10.01 - 10.03; GROUP 10.01 - 10.04 WITHIN 9H; CYCLE 2/10.00 - 10.28; ONBOARD ACQ FOR 10.10 - 10.28; SEQ 10.04 - 10.10 NO GAP; AT 7-OCT-92 08 45 +/- 1M; ONBOARD ACQ FOR 10.260; SEQ 10.26 - 10.28; GROUP 10.10 - 10.28 WITHIN 9H; ONBOARD ACQ FOR 11.01; SEQ 11.00 - 11.01 NO GAP; SEQ 11.01 - 11.03; GROUP 11.01 - 11.04 WITHIN 9H; CYCLE 2/11.00 - 11.28; ONBOARD ACQ FOR 11.10 - 11.28; SEQ 11.04 - 11.10 NO GAP; AT 9-OCT-92 04 53 +/- 1M; ONBOARD ACQ FOR 11.260; SEQ 11.26 - 11.28; GROUP 11.10 - 11.28 WITHIN 9H; ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F750W/F320N ------------------------------------------------------------------------------------------------------------------------------------ Target Names GSC6349-01493 01493-OFFSET GSC6349-01494 01493-A-BACKGROUND 01493-B-BACKGROUND TITAN-CENTER ------------------------------------------------------------------------------------------------------------------------------------