Page 1 PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID 2771c Report Date: 09-May-96:17:19 Version: ********** Check-in Date: ********** 1.Proposal Title: HSP STELLAR OCCULTATION BY PLANETARY RINGS HSP-09A ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Proposal Type 5. Continuation ID SOLAR SYSTEM SV/HSP Sub Category ------------------------------------------------------------------------------------ 6. Principal Investigator Institution Country Telephone Robert C. Bless UNIV.OF WISCONSIN USA 608-262-1715 PROFESSOR ------------------------------------------------------------------------------------ 7. Abstract This proposal defines the procedure for the verification of the occultation mode of observation on the HSP using the beamsplitter to simultaneously observe with both IDT#3(VIS) and the PMT. This test verifies many procedures employed by all occultation observa- tions, through observation of an occultation by a planetary ring system. The effect of the HSP motion on the predicted times of the occultation events minimal. The immersion of a star will be observed for Saturn while tracking on the star. Revision: EER 6/9/89 RPSS V 7.0 Local & RPS; asb @ MIT Jul 28, 1989 14:30; rlw @ STScI Aug 8, 1989 10:30; asb @ MIT Aug 11, 1989 15:00; SAL-M 8/15/89 RPSS V7.2 : Changed INT-ACQ to ONBRD-ACQ & other changes; Changed PMT dark target - SALM 10/12/89; asb @ MIT 19 Mar 1990 13:30: updated target list; asb @ MIT 17 May 1990 11:00: additional targets for SV; pstanley - New RPSS version 5/30/90; Fixed for aberration problem - asb @ MIT 27 July 1990; Changes to targets/observations--amanda; Fixed small syntax error (must specify cycle parameter)--BJW 5/10/91; Changes to observing strategies per 6/4/91 meeting - ps ------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------ 9. Est obs time (hours) pri: 3.00 par: 0 10. Num targs pri: 1 par: 0 ------------------------------------------------------------------------------------ 11. Instruments requested: HSP ------------------------------------------------------------------------------------ 12. Special sched req: Time Critical obs. ------------------------------------------------------------------------------------ Page 2 I. GENERAL FORM Proposal 2771c PI: Robert C. Bless Proposal Title: HSP STELLAR OCCULTATION BY PLANETARY RINGS HSP-09A ------------------------------------------------------------------------------------ 1. Proposers: Proposers Institution Country ESA ------------------------------------------------------------------------------------ Prof Robert Bless UNIV OF WISCONSIN USA J Elliot M I T USA ------------------------------------------------------------------------------------ 2. Scientific Justification. The purpose of this test is to verify the occultation mode on the HSP using the beamsplitter to simultaneously obtain two-color observations with the visual IDT (IDT#3) and the PMT. Additionally, the test specifically supplies the following essential verifications: 1) Tests the ability of the HST to acquire a star near a bright planet using two sequential onboard target acquisitions while the star is still far from the occulting planet. 2) Measures the direct and scattered light essential for planned GTO programs. 3) Check of HSP photometry and data handling in occultation mode. 4) Comparison of observed to calculated predictions to an accuracy of +/- 0.2 sec using ground-based observations of same event if available, establishing the ST/HSP time relatability to UTC. ------------------------------------------------------------------------------------ 3. Description of proposed observations. The proposed observations will use the HSP configured in the HSP/PMT mode requiring single aperture, two detector mode (VIS and the PMT). The observing program will use Saturn as target. Planetary ring occultation: 1) Acquire external "darks", using a dark portion of the sky as a standard calibration source within 3 days of the occultation event. 2) Acquire occultation offset star, using on onboard acquisition raster scan. 3) Perform second acquisition exposure, using results of previous acquisition as input. This will improve the accuracy of the target acquisition. (This is done automatically) 4) Scan along path the star will take during the occultation. 5) Start continuous series of 10 ms integrations for approximately 10 minutes prior to the predicted ring immersion and run for approximately 70 minutes (varies depending on target). ------------------------------------------------------------------------------------ 6. Description of special calibration exposures. Upon placing the star in the beamsplitter aperture and beginning the integration, the immersion sequence must be uninterrupted as the occultation is time critical. ------------------------------------------------------------------------------------ 7. Data reduction and analysis plans. The scattered and direct light measurements from the planetary ring system will be tabulated for future use in determining what stars will be bright enough to provide useful occultation data. The ring occultation times and the HST orbital parameters will be used with current kinematical models to evaluate the precision of HSP occulta- tion photometry and the accuracy of HST timing and orbital positions. ------------------------------------------------------------------------------------ 8. Additional comments or special requests. The observations are inherently time-critical and uninterruptable. It is thus anticipated that use of the onboard tape recorder may be necessary to store the data stream. Simultaneous ground-based observations are highly desirable to provide an independent verification of the spacecraft clock and post-observation spacecraft position in orbit. ------------------------------------------------------------------------------------ 10. Resources to be supplied by investigator's institution(s). Data reduction and analysis will be supported on computer facilities at MIT. Page 3 ------------------------------------------------------------------------------------ 11. Address Information Name: ROBERT C BLESS Category: PI Institution: UNIV OF WISCONSIN Address: 475 N. CHARTER City: MADISON State: WI Zip Code: Country: USA Telephone: 608-262-1715 Telex (or e-mail): ------------------------------------------------------------------------------------ TARGET LIST a) Fixed Targets ID = 2771c [ 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| | | | | | | | | ------------------------------------------------------------------------------------------------------------------------------------ 1 GSC6323- STAR TO BE OCCULTED BY RA = 20H 13M 18.21S +/- J2000 BKG 1 V = 13.0 +/- 0.1 01466 SATURN. 0.5", CLOSE APPROACH AT 5-SEP DEC = -20D 27' 03.9" +/- -91:22:12 0.5", PLATE-ID = 01D0 Comments: COORDS FROM GUIDE STAR CATALOG SOLAR ELONG E140D ------------------------------------------------------------------------------------------------------------------------------------ 2 01466-OFFSET OFFSET STAR TO BE RA = 20H 13M 20.54S +/- 1", J2000 BKG 1 V = 15.3 +/- 0.1 STAR-201321- ACQUIRED DEC = -20D 27' 16.6" +/- 1" 202717 Comments: COORDS FROM PALOMAR SKY SURVEY, WILL PROVIDE POSITION ACCURATE TO WITHIN 0.25" FROM CURRENT ASTROMETRY ------------------------------------------------------------------------------------------------------------------------------------ 3 DARK-PMT RA= 16H 27M 11.0S +/- 0.1S, J2000 DEC= -24D 19' 14.0" +/- 0.1S, Comments: DARK PORTION OF THE SKY FOR PMT DARK MEASUREMENT. ------------------------------------------------------------------------------------------------------------------------------------ TARGET LIST b)Solar System Targets ID = 2771c [ 5] ------------------------------------------------------------------------------------------------------------------------------------ TARGET NUMBER: 4 | TARGET NAME: SATURN-BACKGROUND ------------------------------------------------------------------------------------------------------------------------------------ TARGET DESCRIPTION: OFFSET SATURN ------------------------------------------------------------------------------------------------------------------------------------ TARGET POSITION LEVEL 1 | TARGET POSITION LEVEL 2 | STD=SATURN | TYPE= POS_ANGLE, | RAD = 5, | ANG = 130.45, | REF = NORTH | ------------------------------------------------------------------------------------------------------------------------------------ TARGET POSITION LEVEL 3 | WINDOWS | | ------------------------------------------------------------------------------------------------------------------------------------ REF | DATA | COMMENTS | | | ------------------------------------------------------------------------------------------------------------------------------------ EXPOSURE LOGSHEET ID = 2771c [ 6] ------------------------------------------------------------------------------------------------------------------------------------ 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 120S 1 1 GUID TOL 0.007" ONBRD- VIS ACQ Comments: USE FINE LOCK FOR GUIDE STAR ACQ IF BRIGHT ENOUGH GUIDE STARS CAN BE FOUND. IF NOT, COARSE TRACK IS ACCEPTABLE. ------------------------------------------------------------------------------------------------------------------------------------ 5 DEFINE # HSP/ SPLIT 1.0 F750W/ SAMPLE- 1 5M 1 1 EXT- PMT/ F320N TIME=0.01 DARK VIS DATA-FORMAT=ALL PRECISION=HIGH ANALOG- SCALE=1000 Comments: EXTERNAL STANDARD CALIBRATION. USE GYROS FOR TRACKING. HIGH ACCURACY NOT NEEDED, WANT TO SAVE TIME. ------------------------------------------------------------------------------------------------------------------------------------ 6 DEFINE # HSP/ SPLIT 1.0 F750W/ # 1 1S 1 1 SPATIAL SCAN BACK- PMT/ F320N SINGLE-EXP SCAN VIS GUID TOL 0.007" Comments: USE FINE LOCK FOR GUIDE STAR ACQ IF BRIGHT ENOUGH GUIDE STARS CAN BE FOUND. IF NOT, COARSE TRACK IS ACCEPTABLE. ------------------------------------------------------------------------------------------------------------------------------------ 7 DEFINE # HSP/ SPLIT 1.0 F750W/ # 1 1M 1 1 CRIT OBS RING- PMT/ F320N GUID TOL 0.007" OCC VIS Comments: USE FINE LOCK FOR GUIDE STAR ACQ IF BRIGHT ENOUGH GUIDE STARS CAN BE FOUND. IF NOT, COARSE TRACK IS ACCEPTABLE. ------------------------------------------------------------------------------------------------------------------------------------ 40 USE EXT DARK-PMT GROUP 40-50 WITHIN -DARK 3D CYCLE 0/40-90 ------------------------------------------------------------------------------------------------------------------------------------ 50 USE SATURN- SAMPLE- X107 SEQ 50-70 NO GAP BACK- BACKGROUND TIME=0.01 GROUP 50-90 WITHIN SCAN DATA-FORMAT=ALL 7D PRECISION=HIGH ANALOG- SCALE=1000 Comments: DO LINES 50-70 SCANS AS CLOSE AS POSSIBLE TO 80-90 OCCULTATION. THIS IS IMPORTANT TO THE DATA ANALYSIS BUT THE REQUIREMENTS WERE RELAXED TO ENSURE THE OBSERVATION COULD BE SCHEDULED. (P. STANLEY) ------------------------------------------------------------------------------------------------------------------------------------ EXPOSURE LOGSHEET ID = 2771c [ 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 ------------------------------------------------------------------------------------------------------------------------------------ 60 USE SATURN- SAMPLE- X319 BACK- BACKGROUND TIME=0.01 SCAN DATA-FORMAT=ALL PRECISION=HIGH ANALOG- SCALE=1000 ------------------------------------------------------------------------------------------------------------------------------------ 70 USE GSC6323- SAMPLE- X107 BACK- 01466 TIME=0.01 SCAN DATA-FORMAT=ALL PRECISION=HIGH ANALOG- SCALE=1000 ------------------------------------------------------------------------------------------------------------------------------------ 80 USE 01466- ONBOARD ACQ FOR 90 ONBRD- OFFSET SEQ 80-90 NO GAP ACQ ------------------------------------------------------------------------------------------------------------------------------------ 90 USE GSC6323- SAMPLE- X32 AT 6-SEP-91:00:47 RING- 01466 TIME=0.10 +/- 5M OCC PRECISION=HIGH DATA-FORMAT=ALL ANALOG- SCALE=1000 Comments: END EXPOSURE AT 6-SEP-91:01:12 START AT 6-SEP-91:00:42 ASSUME SPSS WILL PUT THIS AT START OF WINDOW IF POSSIBLE. EXP TIME IS SHORTER THAN THAT CALC FROM START- STOP TIMES TO ACCT FOR EARTH OCCLS ------------------------------------------------------------------------------------------------------------------------------------ Scan Paramters Form Proposal ID: 2771c [ 8] ------------------------------------------------------------------------------------------------------------------------------------ Data ID: 1 Exposure Logsheet lines: 50, 70 FGS Scan: CONTINUOUS Dwell Only: dwell points/line: 0 Seconds per dwell: 0.00 Scan width (arc-secs): 0.0000 Scan length (arc-secs): 21.2700 Angle between sides (degrees) 90.00 Number of lines: 1 Scan rate (arc-sec/sec): 0.2000 PA of first scan line (degrees) 76.450 Scan frame (CEL or S/C): CEL Length Offset (arc-sec): 0. Width Offset (arc-sec): 0. ------------------------------------------------------------------------------------------------------------------------------------ Data ID: 2 Exposure Logsheet lines: 60 FGS Scan: CONTINUOUS Dwell Only: dwell points/line: 0 Seconds per dwell: 0.00 Scan width (arc-secs): 1.0000 Scan length (arc-secs): 21.2700 Angle between sides (degrees) 90.00 Number of lines: 3 Scan rate (arc-sec/sec): 0.2000 PA of first scan line (degrees) 76.450 Scan frame (CEL or S/C): CEL Length Offset (arc-sec): 0. Width Offset (arc-sec): 0.5000 ------------------------------------------------------------------------------------------------------------------------------------ Summary Form for Proposal 2771c [ 9] Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations HSP/VIS HSP/PMT/VIS ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACQ SPLIT ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters SAMPLE-TIME=0.01 DATA-FORMAT=ALL PRECISION=HIGH ANALOG-SCALE=1000 SAMPLE-TIME=0.10 ------------------------------------------------------------------------------------------------------------------------------------ Proposal for SV/HSP ------------------------------------------------------------------------------------------------------------------------------------ S/C Hours 3.00 ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category SOLAR SYSTEM ------------------------------------------------------------------------------------------------------------------------------------ Scientific Sub-category ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements GUID TOL 0.007"; SPATIAL SCAN SINGLE-EXP; CRIT OBS; GROUP 40-50 WITHIN 3D; CYCLE 0/40-90; SEQ 50-70 NO GAP; GROUP 50-90 WITHIN 7D; ONBOARD ACQ FOR 90; SEQ 80-90 NO GAP; AT 6-SEP-91 00 47 +/- 5M; ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F750W/F320N ------------------------------------------------------------------------------------------------------------------------------------ Target Names GSC6323-01466 01466-OFFSET STAR-201321-202717 DARK-PMT SATURN-BACKGROUND ------------------------------------------------------------------------------------------------------------------------------------