! File: 4944C.PROP ! Database: PEPDB ! Date: 23-FEB-1994:11:41:55 coverpage: title_1: OPPORTUNITY OCCULTATIONS BY SMALL BODIES - SPLIT - CYC3HIGH sci_cat: SOLAR SYSTEM proposal_for: GTO/HSP targ_of_opp: Y cont_id: 4442 pi_fname: ROBERT pi_mi: C. pi_lname: BLESS pi_inst: WISCONSIN, UNIVERSITY OF pi_country: USA pi_phone: (608)262-1715 keywords_1: COMET, ASTEROID, SATELLITE, PLUTO, OCCULTATION hours_pri: 1.48 num_pri: 1 realtime: X time_crit: Y ! end of coverpage abstract: line_1: Although an occultation by any specific comet, line_2: asteroid, satellite, or Pluto is unlikely to be line_3: observable from the ST, the scientific return from line_4: such an event would be great because of the superior line_5: signal-to-noise ratio achievable with the ST for line_6: occultation observations. We propose to observe line_7: occultations by these bodies with the ST, as the line_8: opportunites arise, to probe their atmospheres, line_9: determine their sizes and achieve other goals. With line_10: such diverse possibilities, one must examine each line_11: opportunity as it occurs and formulate an observing line_12: strategy to fit that particular case. Revision line_13: History: Recvd on RPS 9/1/89;Added to SCCS 9/5/89; line_14: V2 prop instr - SALM; asb@MIT 5/7/90; Small logic line_15: errors fixed, BJW 7/9/90; Changed SP SCAN to SP SCAN line_16: SING-EXP, BJW 7/10/90; Target changes, ASB; Split by line_17: cycle, BJW 4/24/91; Updated targets, BJW 8/1/91; line_18: Updated targets, ASB 3/18/92; Cycle 2 changes, ASB line_19: 1/24/93 SPLIT FROM 4442 BEC. 2 TARGETS IN 4442 line_20: ALREADY EXECUTED; ! ! 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 identify those occultations of sufficient line_2: signal-to-noise ratio to achieve the goals outlined line_3: in Section 2. Each observation will require (i) a line_4: set of 2 onboard acquisitions; and (ii) line_5: a time series run on the object with whatever filter line_6: aperture combination that is chosen for the line_7: observation. For some occultations to be observed in line_8: the far UV, prior multi-filter photometry of the line_9: object will be necessary in order to determine the line_10: most appropriate filter to use for the occultation. line_11: For now, we shall assume that the calibration and line_12: observation time will average about 30 minutes per line_13: occultation observed. ! question: 4 section: 1 line_1: We can achieve a much better signal-to-noise ratio line_2: for the temperature profiles and other information line_3: than can be obtained for small body occultations line_4: than has been possible from the ground for the line_5: following reasons: (i) the greatly improved line_6: photometric stability of ST photometry, which will line_7: substantially reduce the errors in the numerical line_8: inversion of the data that is necessary to obtain line_9: the temperature profiles; (ii) our ability to reject line_10: background light from the occulting object (such as line_11: a comet ) by employing small focal plane apertures; line_12: and (iii) the absence of scintillation noise, which line_13: has strong components at frequencies comparable to line_14: the occultation timescale. ! question: 7 section: 1 line_1: Data will be reduced and analyzed at MIT with DEC line_2: 5000 belonging to the planetary astronomy group. ! question: 10 section: 1 line_1: TBD ! question: 13 section: 1 line_1: An observation of an occultation by a comet, line_2: asteroid, satellite, or Pluto would yield a variety line_3: of information. For example, we could gain further line_4: information about the atmospheres of Pluto and line_5: Triton, including knowledge of the composition and line_6: structure of their atmospheres. Also, the presence line_7: of possible material in the neighborhood of an line_8: asteroid could be obtained. Opportunity stellar line_9: occultations by small bodies are proposed to be line_10: observed with the HSP or FOS. ! !end of general form text general_form_address: lname: BLESS fname: ROBERT mi: C. category: PI inst: WISCONSIN, UNIVERSITY OF addr_1: DEPARTMENT OF ASTRONOMY addr_2: 475 NORTH CHARTER STREET city: MADISON state: WI zip: 53706 country: USA phone: 608-262-1715 ! ! end of general_form_address records fixed_targets: targnum: 18 name_1: TR46 name_2: GSC6310-02742 descr_1: STAR TO BE OCCULTED BY TRITON. descr_2: CLOSE APPROACH AT 13-MAY-93:06:46 pos_1: PLATE-ID = 0104, pos_2: RA = 19H 30M 55.294S +/- 0.03", pos_3: DEC = -21D 06' 23.79" +/- 0.06", equinox: J2000 acqpr_1: BKG comment_1: SOLAR ELONG 121 fluxnum_1: 1 fluxval_1: R = 13.4 +/- 0.5 ! targnum: 19 name_1: TR46-OFFSET name_2: GSC6310-01521 descr_1: OFFSET TARGET FOR TR46 pos_1: PLATE-ID = 0104, pos_2: RA = 19H 30M 53.111S +/- 0.03", pos_3: DEC = -21D 06' 04.72" +/- 0.05", equinox: J2000 fluxnum_1: 1 fluxval_1: R = 14.14 +/- 0.10 ! ! end of fixed targets ! No solar system records found ! 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 ! 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: # ! linenum: 7.100 sequence_1: DEFINE sequence_2: RING-OCC targname: ^ config: S/C opmode: DATA aperture: NONE num_exp: 1 time_per_exp: 0S priority: 1 param_1: FORMAT=FN, req_1: PAR WITH 7.0; comment_1: CAPTURE FGS TLM DURING OCCULTATION. ! linenum: 7.200 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: # ! linenum: 7.300 sequence_1: DEFINE sequence_2: RING-OCC targname: ^ config: S/C opmode: DATA aperture: NONE num_exp: 1 time_per_exp: 0S priority: 1 param_1: FORMAT=FN, req_1: PAR WITH 7.2; comment_1: CAPTURE FGS TLM DURING OCCULTATION. ! linenum: 50.040 sequence_1: USE sequence_2: ONBRD-ACQ targname: TR46-OFFSET time_per_exp: X100 req_1: ONBOARD ACQ FOR 50.10; req_2: SEQ 50.04 - 50.10 NO GAP; req_3: PCS MODE F / 50.04 - 50.10; req_4: CYCLE 2/50.04 - 50.10; comment_1: USE FINE LOCK FOR OBSERVATION IF comment_2: BRIGHT ENOUGH GUIDE STARS CAN BE comment_3: FOUND. IF NOT, COARSE TRACK IS comment_4: ACCEPTABLE. ! linenum: 50.100 sequence_1: USE sequence_2: RING-OCC targname: TR46 time_per_exp: X30 param_1: SAMPLE-TIME = 0.01, param_2: DATA-FORMAT = ALL, param_3: PMT-ANALOG = 100, param_4: VIS-ANALOG = 100, req_1: AT 13-MAY-93:06:21 +/- 1M; req_2: CRIT OBS; comment_1: END EXPOSURE AT 13-MAY-93:07:20. ! ! end of exposure logsheet ! No scan data records found