! File: 3375C.PROP ! Database: PEPDB ! Date: 19-FEB-1994:05:28:08 coverpage: title_1: SATURN RING DYNAMICS - CYCLE 2 sci_cat: SOLAR SYSTEM proposal_for: GTO/HSP cont_id: 1081 pi_fname: ROBERT pi_mi: C. pi_lname: BLESS pi_inst: WISCONSIN, UNIVERSITY OF pi_country: USA pi_phone: 608-262-1715 keywords_1: SATURN'S RINGS, OCCULTATIONS, RING DYNAMICS hours_pri: 9.50 num_pri: 17 hsp: Y time_crit: Y ! end of coverpage abstract: line_1: Understanding the dynamics of the rings is essential line_2: to our eventual understanding of their origin. Did line_3: they form recently or along with Saturn itself? We line_4: propose a series of stellar occultation observations line_5: in order to continue the dynamical investigation of line_6: Saturn's rings, at high spatial resolution, begun by line_7: the Voyager spacecraft. Revision History: Received line_8: on RPS 9/1/89; Added to SCCS 9/5/89 RPSS V7.2 local line_9: & remote; fixed up small syntax errors - SALM 9/5/89 line_10: Updated for cycle 1 -- amanda bosh (MIT) 28 Sept 89 line_11: asb @ MIT 19 Mar 1990: Updated cycle 1 targets; line_12: SPATIAL SCANs, GUID TOL changes etc. - asb@MIT line_13: 23May90; Small logic errors fixed--BJW 7/9/90; line_14: revised changes to SEQ--BJW 7/31/90; Change cycle 0 line_15: to cycle 8 on line 110.040--BJW 11/28/90; Changes to line_16: observations/targets--amanda; Split proposal by line_17: cycle--BJW 5/2/91; ! ! end of abstract general_form_proposers: lname: ROBINSON fname: EDWARD mi: L. inst: TEXAS, UNIVERSITY OF country: USA ! lname: BLESS fname: ROBERT mi: C. inst: WISCONSIN, UNIVERSITY OF country: USA ! lname: VAN CITTERS fname: G. mi: W. inst: NATIONAL SCIENCE FOUNDATION country: USA ! lname: DOLAN fname: JOSEPH mi: F. inst: NASA, GODDARD SPACE FLIGHT CENTER country: USA ! lname: WHITE fname: RICHARD mi: L. inst: SPACE TELESCOPE SCIENCE INSTITUTE country: USA ! lname: ELLIOT fname: JAMES mi: L. inst: MASSACHUSETTS INSTITUTE OF TECHNOLOGY country: USA ! ! end of general_form_proposers block general_form_text: question: 3 section: 1 line_1: We plan to use the ST orbit parameters and catalogs line_2: of the objects of interest to identify those line_3: occultations of sufficient signal-to-noise ratio to line_4: achieve the goals outlined in Section 2. Each line_5: observation will require (i) a set of two sequential line_6: acquisitions, (ii) a scan of about 30-40 arcseconds line_7: along the track that the object will follow relative line_8: to Saturn's rings; and (iii) a time series run on line_9: the object with whatever filter-aperture combination line_10: that is chosen for the observation. For some line_11: occultations to be observed in the far uv, prior line_12: multi-filter photometry of the object will be line_13: necessary in order to determine the most appropriate line_14: filter to use for the occultation. The default line_15: filter set is F750W/F320N. For now, we shall assume line_16: that the calibration and observation time will line_17: average about 3 hours per occultation observed. line_18: About ten occultations would be required to achieve line_19: our goals of establishing orbits for the ringlets line_20: and other sharp-edged features of the system. For at ! question: 4 section: 1 line_1: We can achieve a much better signal-to-noise ratio line_2: for Saturn ring occultations than would be possible line_3: from the ground because of (i) the absence of line_4: scintillation noise, which has strong components at line_5: frequencies corresponding to the occultation line_6: timescales, and (ii) our ability to reject line_7: background light from the rings themselves by line_8: employing small focal plane apertures. ! question: 5 section: 1 line_1: Acquisition of the star near Saturn may prove to be line_2: difficult. ! question: 6 section: 1 line_1: A prior scan over 30-40 arcseconds is needed to map line_2: the scattered light field, which is needed for the line_3: data reduction. ! question: 7 section: 1 line_1: Data will be reduced and analyzed at MIT with the line_2: VAX 11-750 belonging to the planetary astronomy line_3: group. ! question: 8 section: 1 line_1: SV test HSP09A must be completed before these observations line_2: are made because the exact observation sequence may need line_3: to be modified depending on the results of the SV test. ! question: 10 section: 1 line_1: Data reduction and analysis will be supported on computer line_2: facilities at MIT. ! question: 13 section: 1 line_1: Observations of a series of stellar occultations by line_2: Saturn's rings with the HSP (or perhaps FOS) can line_3: provide precise orbits of ringlets, other sharp line_4: features, waves, and other phenomena in the Saturn line_5: system at high spatial resolution. From these data line_6: further understanding of the present dynamical state line_7: of the ring system can be gained. This understanding line_8: should improve our knowledge of the past history and line_9: conditions of formation of the rings. ! !end of general form text general_form_address: lname: BLESS fname: ROBERT mi: C. category: PI inst: UNIVERSITY OF WISCONSIN addr_1: DEPARTMENT OF ASTRONOMY city: MADISON state: WI zip: 53706 country: USA phone: 608-262-1715 ! lname: ELLIOT fname: JAMES mi: L. category: CON inst: MASSACHUSETTS INSTITUTE OF TECHNOLOGY addr_1: BLDG. 54-422 city: CAMBRIDGE state: MA zip: 02139 country: USA phone: 617-253-6308 telex: 921473 MIT CAM ! ! end of general_form_address records fixed_targets: targnum: 11 name_1: GSC6347-01433 descr_1: A,140 pos_1: PLATE-ID = 02JD, pos_2: RA = 21H 19M 05.47S +/- 0.1", pos_3: DEC = -16D 39' 49.46" +/- 0.1" equinox: J2000 acqpr_1: BKG comment_1: TARGET DESCR. STAR TO BE OCCULTED comment_2: BY SATURN. CLOSE APPROACH AT comment_3: 13-JUL-92:05:48 comment_4: SOLAR ELONG 154D fluxnum_1: 1 fluxval_1: V = 10.95 +/- 0.3 ! ! end of fixed targets solar_system_targets: targnum: 18 name_1: 01433-BACKGROUND descr_1: OFFSET SATURN lev1_1: STD = SATURN lev2_1: TYPE = POS_ANGLE, lev2_2: RAD = 38.2, lev2_3: ANG = 69, lev2_4: REF = NORTH comment_1: FOR USE IN A SCAN OF comment_2: BACKGROUND LEVELS ALONG comment_3: THE PATH OF THE OCCULTED STAR ! ! end of solar system targets ! No generic target records found exposure_logsheet: linenum: 4.000 sequence_1: DEFINE sequence_2: ONBRD-ACQ targname: # config: HSP/VIS opmode: ACQ num_exp: 1 time_per_exp: 1S fluxnum_1: 1 priority: 1 req_1: PCS MODE F; comment_1: USE FINE LOCK FOR OFFSET TARGET ACQ comment_2: IF BRIGHT ENOUGH GUIDE STARS CAN BE comment_3: FOUND. IF NOT, COARSE TRACK IS comment_4: ACCEPTABLE. ! linenum: 6.000 sequence_1: DEFINE sequence_2: BACK-SCAN targname: # config: HSP/PMT/VIS opmode: SPLIT aperture: 1.0 sp_element: F750W/F320N num_exp: 1 time_per_exp: 1S fluxnum_1: 1 priority: 1 param_1: # req_1: SPATIAL SCAN; comment_1: USE FINE LOCK FOR OFFSET TARGET ACQ comment_2: IF BRIGHT ENOUGH GUIDE STARS CAN BE comment_3: FOUND. IF NOT, COARSE TRACK IS comment_4: ACCEPTABLE. ! linenum: 7.000 sequence_1: DEFINE sequence_2: RING-OCC targname: # config: HSP/PMT/VIS opmode: SPLIT aperture: 1.0 sp_element: F750W/F320N num_exp: 1 time_per_exp: 1M fluxnum_1: 1 priority: 1 param_1: # req_1: CRIT OBS; req_2: PCS MODE F; comment_1: USE FINE LOCK FOR OFFSET TARGET ACQ comment_2: IF BRIGHT ENOUGH GUIDE STARS CAN BE comment_3: FOUND. IF NOT, COARSE TRACK IS comment_4: ACCEPTABLE. ! linenum: 10.010 sequence_1: USE sequence_2: BACK-SCAN targname: 01433-BACKGROUND time_per_exp: X613 param_1: SAMPLE-TIME = 0.05, param_2: PRECISION = HIGH, param_3: DATA-FORMAT = ALL, param_4: PMT-ANALOG = 1000, param_5: VIS-ANALOG = 100, req_1: SEQ 10.01 - 10.03; req_2: GROUP 10.01 - 10.04 WITHIN 9H; req_3: CYCLE 2/10.01 - 10.10; ! linenum: 10.020 sequence_1: USE sequence_2: BACK-SCAN targname: 01433-BACKGROUND time_per_exp: X613 param_1: SAMPLE-TIME = 0.1, param_2: PRECISION = HIGH, param_3: DATA-FORMAT = ALL, param_4: PMT-ANALOG = 1000, param_5: VIS-ANALOG = 100, ! linenum: 10.030 sequence_1: USE sequence_2: BACK-SCAN targname: 01433-BACKGROUND time_per_exp: X613 param_1: SAMPLE-TIME = 0.05, param_2: PRECISION = HIGH, param_3: DATA-FORMAT = ALL, param_4: PMT-ANALOG = 1000, param_5: VIS-ANALOG = 100, ! linenum: 10.040 sequence_1: USE sequence_2: ONBRD-ACQ targname: GSC6347-01433 time_per_exp: X20 req_1: ONBOARD ACQ FOR 10.10; req_2: SEQ 10.04 - 10.10 WITHIN 60M; ! linenum: 10.100 sequence_1: USE sequence_2: RING-OCC targname: GSC6347-01433 time_per_exp: X127 param_1: SAMPLE-TIME = 0.1, param_2: PRECISION = HIGH, param_3: DATA-FORMAT = ALL, param_4: PMT-ANALOG = 1000, param_5: VIS-ANALOG = 100, req_1: AT 13-JUL-92:04:01 +/- 1M; comment_1: END EXPOSURE AT 13-JUL-92:07:15. ! ! end of exposure logsheet scan_data: line_list: 10.01, 10.03 fgs_scan: cont_dwell: C dwell_pnts: 0 dwell_secs: 0.00 scan_width: 0.0000 scan_length: 68.5000 sides_angle: 90.0000 number_lines: 1 scan_rate: 0.0750 first_line_pa: 251.0000 scan_frame: CEL len_offset: 0. wid_offset: 0. ! line_list: 10.02 fgs_scan: cont_dwell: C dwell_pnts: 0 dwell_secs: 0.00 scan_width: 3.0000 scan_length: 68.5000 sides_angle: 90.0000 number_lines: 5 scan_rate: 0.0750 first_line_pa: 251.0000 scan_frame: CEL len_offset: 0. wid_offset: 1.5 ! ! end of scan data