! File: 2923C.PROP ! Database: PEPDB ! Date: 17-FEB-1994:22:03:38 coverpage: title_1: ASTROMETRY THERMAL TEST proposal_for: OV/2 pi_fname: WILLIAM pi_mi: H. pi_lname: JEFFERYS pi_inst: TEXAS, UNIVERSITY OF pi_country: USA pi_phone: 512-471-1455 keywords_1: FGS, ASTROMETRY hours_pri: 4.00 num_pri: 4 fgs: Y time_crit: Y pi_position: PROFESSOR ! end of coverpage abstract: line_1: The Astrometry Science Team will characterize the response of all line_2: FGS units to a changing HST thermal environment. By doing this test line_3: immediately after the WFPC UV flood test done during a series of "cold" line_5: orbits, we can determine changes in FGS behavior with timescales of 4 hours. line_6: We can also monitor diurnal changes during the roughly 3 orbits required line_7: for this test. ! ! end of abstract general_form_proposers: lname: JEFFERYS fname: WILLIAM mi: H. inst: TEXAS, UNIVERSITY OF country: USA ! lname: SHELUS fname: PETER mi: J. inst: TEXAS, UNIVERSITY OF country: USA ! lname: HEMENWAY fname: PAUL mi: D. inst: TEXAS, UNIVERSITY OF country: USA ! lname: FREDRICK fname: LAURENCE mi: W. inst: VIRGINIA, UNIVERSITY OF country: USA ! lname: VAN ALTENA fname: WILLIAM mi: F. inst: YALE UNIVERSITY country: USA ! lname: BENEDICT fname: GEORGE mi: F. inst: TEXAS, UNIVERSITY OF country: USA ! lname: DUNCOMBE fname: RAYNOR mi: L. inst: TEXAS, UNIVERSITY OF country: USA ! lname: FRANZ fname: OTTO mi: G. inst: LOWELL OBSERVATORY country: USA ! ! end of general_form_proposers block general_form_text: question: 2 section: 1 line_1: The Team beleives that a rigorous thermal characterization of the inter-FGS line_2: response to a changing thermal environment is absolutely critical to Astrometry line_3: Science. line_4: Astrometric measurements at the projected 0.002 arcseconds level of accuracy line_5: require intra-FGS measurements within the "Astrometer" FGS. The intra-FGS line_6: measurements are made on one object at a time. Thus the relative accuracy of line_7: the target with respect to the reference objects depends on the FGS instrumental line_8: system remaining fixed on the sky. This depends on the guiding FGSs holding HST line_9: fixed with respect to the guide stars, and HST holding the astrometer fixed line_10: with respect to the guiding FGSs during the astrometric measuring sequence. line_11: Because thermal variations may cause the FGSs to move with respect to each other line_12: at the 0.01 arcsecond level, and because we are trying to measure relative line_14: positions to 0.002 arcseconds or better, the Astrometry OV thermal test was line_15: designed to characterize the amplitudes and timescales for the inter-FGS motions line_16: induced by cycling into and out of shadow, and from a worst case thermal slew line_17: (hot to cold or cold to hot). Without such a test we can have little confidence line_18: in the integrity of our science data, even with some simple "check" measurements line_19: in an observing sequence. ! question: 3 section: 1 line_1: Immediately after the WFPC UV Flood Test (proposal 1478) line_2: 1) slew to South Ecliptic Pole line_3: 2) acquire guide stars line_4: 3) acquire first target line_5: 4) observe in FGS Pos mode for 3 minutes line_6: 5) acquire second target line_7: 6) observe in FGS Pos mode for 1 minute line_8: 7) acquire third target line_9: 8) observe 1 minute line_10: 9) acquire fourth target line_11: 10) observe 1 minute line_12: 11) repeat steps 3-10 20 times ! question: 4 section: 1 line_1: We must test the FGS units during HST operations. ! question: 5 section: 1 line_1: To asses the effects of a changing thermal environment we must stay in "cold" line_2: for a reasonable length of time, then remain in a "hot" state. The UV Flood line_3: Test is expected to keep the HST in a "cold" state for approximately 5 hours. line_4: We wish to keep HST in a "hot" state for the same time duration. Hence, we line_5: remain pointed at targets near the South Ecliptic Pole for about 5 hours, line_6: repeating observations of our targets. ! question: 6 section: 1 line_1: TEST MUST IMMEDIATELY FOLLOW WFPC UV FLOOD GUIDE TEST (PROPOSAL 1478) line_2: PRESENTLY SCHEDULED IN WEEK 3 OF OV/2 line_3: The slew from the anti-sun point (the target for proposal 1478) line_4: to the South Ecliptic Pole ( the target for this proposal) line_5: should be timed so that the guide star acquisition for 1418 line_6: can start at the beginning of the visibilty period. This line_7: insures that we begin observing thermal effects as soon as line_8: possible. ! question: 7 section: 1 line_1: Guide star and target data will be analyzed to determine magnitude of intra and line_2: inter FGS positional changes throughout the approximately 5 hour hot state. line_3: We will utilize STScI SDAS (ADRS within SDAS) and models developed to line_4: incorporate temporal changes. ! question: 8 section: 1 line_1: Must coordinate with proposal 1478. line_2: Must override SAA AVOIDANCE RULE FOR THIS TEST ONLY. ! question: 10 section: 1 line_1: On site data processing equipment at UTEXAS ! !end of general form text general_form_address: lname: JEFFERYS fname: WILLIAM mi: H. title: DR category: PI inst: TEXAS, UNIVERSITY OF city: AUSTIN state: TX country: USA ! lname: BENEDICT fname: GEORGE mi: F. category: CON inst: UNIVERSITY OF TEXAS addr_1: ASTRONOMY DEPARTMENT city: AUSTIN state: TX zip: 78712 country: USA phone: 512-471-3448 ! ! end of general_form_address records fixed_targets: targnum: 1 name_1: THERM1 descr_1: STAR pos_1: RA = 05H 53M 01.66S +/- 1", pos_2: DEC = -64D 44' 52.08" +/- 1" equinox: 2000.0 pm_or_par: N comment_1: NEW TARGET (5/90) fluxnum_1: 1 fluxval_1: V = 13.18 ! targnum: 2 name_1: THERM1-1-REF descr_1: ^ pos_1: RA = 05H 53M 15.43S +/- 1", pos_2: DEC = -64D 44' 03.48" +/- 1" equinox: ^ pm_or_par: ^ comment_1: NEW TARGET (5/90) fluxnum_1: 1 fluxval_1: V=13.83 ! targnum: 3 name_1: THERM1-2-REF descr_1: ^ pos_1: RA = 05H 52M 13.56S +/- 1", pos_2: DEC = -64D 43' 40.80" +/- 1" equinox: ^ pm_or_par: ^ comment_1: NEW TARGET (5/90) fluxnum_1: 1 fluxval_1: V=11.77 ! targnum: 4 name_1: THERM1-3-REF descr_1: ^ pos_1: RA = 05H 53M 43.87S +/- 1", pos_2: DEC = -64D 42M 47.88" +/- 1" equinox: ^ pm_or_par: ^ comment_1: NEW TARGET (5/90) fluxnum_1: 1 fluxval_1: V=14.52 ! ! end of fixed targets ! No solar system records found ! No generic target records found exposure_logsheet: linenum: 1.000 sequence_1: DEFINE sequence_2: THERMAL targname: THERM1 config: FGS opmode: POS aperture: 2 sp_element: F550W num_exp: 1 time_per_exp: 3M fluxnum_1: 1 param_1: DATA-RATE=32 req_1: SEQ 1-2 NON-INT; req_2: CRITICAL OBS; req_3: NON-INT; ! linenum: 2.000 sequence_1: DEFINE sequence_2: THERMAL targname: THERM1-1-REF config: ^ opmode: ^ aperture: ^ sp_element: ^ num_exp: ^ time_per_exp: 1M fluxnum_1: ^ param_1: ^ req_1: NON-INT; req_2: DO FOR TARGETS 2-4; ! linenum: 3.000 sequence_1: USE sequence_2: THERMAL req_2: SEQ 3-22 NO GAP; comment_4: TARGET VISIBILITY PERIOD. comment_5: TERMINATE TEST AFTER 3 ORBITS. ! linenum: 4.000 sequence_1: USE sequence_2: THERMAL ! linenum: 5.000 sequence_1: USE sequence_2: THERMAL ! linenum: 6.000 sequence_1: USE sequence_2: THERMAL ! linenum: 7.000 sequence_1: USE sequence_2: THERMAL ! linenum: 8.000 sequence_1: USE sequence_2: THERMAL ! linenum: 9.000 sequence_1: USE sequence_2: THERMAL ! linenum: 10.000 sequence_1: USE sequence_2: THERMAL ! linenum: 11.000 sequence_1: USE sequence_2: THERMAL ! linenum: 12.000 sequence_1: USE sequence_2: THERMAL ! linenum: 13.000 sequence_1: USE sequence_2: THERMAL ! linenum: 14.000 sequence_1: USE sequence_2: THERMAL ! linenum: 15.000 sequence_1: USE sequence_2: THERMAL ! linenum: 16.000 sequence_1: USE sequence_2: THERMAL ! linenum: 17.000 sequence_1: USE sequence_2: THERMAL ! linenum: 18.000 sequence_1: USE sequence_2: THERMAL ! linenum: 19.000 sequence_1: USE sequence_2: THERMAL ! linenum: 20.000 sequence_1: USE sequence_2: THERMAL ! linenum: 21.000 sequence_1: USE sequence_2: THERMAL ! linenum: 22.000 sequence_1: USE sequence_2: THERMAL ! ! end of exposure logsheet ! No scan data records found