! File: 3062C.PROP ! Database: PEPDB ! Date: 18-FEB-1994:13:50:47 coverpage: title_1: HST OBSERVATIONS OF COMET LEVY (1990C) sci_cat: SOLAR SYSTEM proposal_for: GO/DD pi_title: DR. pi_fname: HAROLD pi_mi: A. pi_lname: WEAVER pi_inst: STSCI pi_country: USA pi_phone: 301-338-4765 keywords_1: COMET hours_pri: 0.01 num_pri: 1 wf_pc: X time_crit: X funds_date: NOV-90 pi_position: DR. off_fname: H. off_mi: S. off_lname: STOCKMAN off_title: DEPUTY DIRECTOR off_inst: SPACE TELESCOPE SCIENCE INSTITUTE off_addr_1: 3700 SAN MARTIN DRIVE off_city: BALTIMORE off_state: MD off_zip: 21218 off_country: USA off_phone: 301-338-4730 ! end of coverpage abstract: line_1: Comet Levy (1990c) is a bright, new comet that passes line_2: very close to the Earth in Sept., 1990. Imaging observations line_3: of this comet by HST will provide unprecedented spatial line_4: resolution of the near nucleus region. WFPC images of line_5: the comet should be obtained as often as possible during line_6: this period. The optimum observing period is during line_7: the first week of September +/- two weeks (approximately). ! ! end of abstract general_form_proposers: lname: WEAVER fname: HAROLD title: P.I. mi: A. inst: STSCI country: USA ! ! end of general_form_proposers block general_form_text: question: 3 section: 1 line_1: These observations will be executed in the "point and shoot" line_2: mode. No tracking of this target will be attempted. The line_3: HST will be commanded to point at a particular (RA,DEC) at line_4: a particular time. In this sense, the four different science line_5: exposures will be treated as pointings at four different line_6: targets. For the first pointing, GS acq to COARSE TRACK line_7: is requested. Following the first exposure, break GS lock line_8: and slew to the next position (the second pointing). All line_9: subsequent exposures will be under gyro control only. The line_10: four science exposures naturally form a "group", but one line_11: or more exposure may be dropped if all exposures cannot be line_12: fit into one observability window. This group of exposures line_13: should be repeated as often as possible during the line_14: observability window. ! question: 6 section: 1 line_1: These observations are possible only during a two week line_2: window centered on May 25, 1990. ! question: 8 section: 1 line_1: These observations occur during OV. Since this comet is "new", line_2: updates to the orbital elements should be performed at the line_3: latest possible time. Since the comet passes relatively close line_4: to the Earth, the parallax correction is roughly 78 arcsec. line_5: Care must be exercised to ensure that the parallax correction line_6: is done properly. ! !end of general form text general_form_address: lname: WEAVER fname: HAROLD mi: A. category: PI inst: STSCI ! ! end of general_form_address records ! No fixed target records found solar_system_targets: targnum: 1 name_1: COMET-LEVY-1990C descr_1: COMET LEVY 1990C lev1_1: TYPE = COMET, Q = 0.9385760, lev1_2: E = 1.0002440, I = 131.58533, lev1_3: O = 138.66367, W = 242.68127, lev1_4: T = 24-OCT-90:16:44:47, lev1_5: EQUINOX = B1950, lev1_6: EPOCH = 10-SEP-90 comment_1: OPTIMUM OBSERVING TIME IS NEAR comment_2: CLOSEST APPROACH TO EARTH. comment_3: NOMINALLY THIS WILL OCCUR comment_4: DURING LATE AUG AND EARLY SEPT. comment_5: TOTAL COMA VISUAL MAGNITUDE SHOULD comment_6: BE ABOUT 3.5 DURING THE TIME OF comment_7: OBSERVATIONS BUT THIS IS comment_8: UNCERTAIN. fluxnum_1: 1 fluxval_1: SURF(V) = 14 +/- 1 fluxnum_2: 2 fluxval_2: SIZE = 0.1 ! ! end of solar system targets ! No generic target records found exposure_logsheet: linenum: 1.000 sequence_1: DEFINE sequence_2: IMAGE targname: COMET-LEVY-1990C config: WFC opmode: IMAGE aperture: ALL sp_element: F785LP num_exp: 1 time_per_exp: 0.11 S s_to_n: 10 fluxnum_1: 1 fluxnum_2: 2 priority: 1 param_1: PRE-FLASH=YES req_1: SEQ 1-4 NON-INT comment_1: EL 1-4 FORM A GROUP BUT SOME CAN BE comment_2: DROPPED IF ALL CANNOT FIT IN ONE comment_3: ORBIT. OPTIMUM DATE FOR COMET comment_4: OBS IS SEPT 3. WINDOW EXTENDS comment_5: INTO LATE SEPTEMBER AND EARLY comment_6: OCTOBER. ! linenum: 2.000 sequence_1: DEFINE sequence_2: IMAGE targname: COMET-LEVY-1990C config: WFC opmode: IMAGE aperture: ALL sp_element: F785LP num_exp: 1 time_per_exp: 0.5 S s_to_n: 21 fluxnum_1: 1 fluxnum_2: 2 priority: 2 param_1: PRE-FLASH=YES ! linenum: 3.000 sequence_1: DEFINE sequence_2: IMAGE targname: COMET-LEVY-1990C config: WFC opmode: IMAGE aperture: ALL sp_element: F785LP num_exp: 1 time_per_exp: 2 S s_to_n: 43 fluxnum_1: 1 fluxnum_2: 2 priority: 3 param_1: PRE-FLASH=YES ! linenum: 4.000 sequence_1: DEFINE sequence_2: IMAGE targname: COMET-LEVY-1990C config: WFC opmode: IMAGE aperture: ALL sp_element: F439W num_exp: 1 time_per_exp: 0.5 S s_to_n: 10 fluxnum_1: 1 fluxnum_2: 2 priority: 4 param_1: PRE-FLASH=YES ! linenum: 5.000 sequence_1: USE IMAGE comment_1: IDEA HERE IS TO GET AS MANY IMAGES comment_2: AS POSSIBLE. EVEN ONE EXECUTION OF comment_3: THE SEQUENCE WILL SATISFY THE comment_4: MINIMUM GOALS OF THE PROGRAM, BUT comment_5: MULTIPLE EXECUTIONS ARE DESIRABLE. ! linenum: 6.000 sequence_1: USE IMAGE ! linenum: 7.000 sequence_1: USE IMAGE ! linenum: 8.000 sequence_1: USE IMAGE ! linenum: 9.000 sequence_1: USE IMAGE ! linenum: 10.000 sequence_1: USE IMAGE ! linenum: 11.000 sequence_1: USE IMAGE ! linenum: 12.000 sequence_1: USE IMAGE ! linenum: 13.000 sequence_1: USE IMAGE ! linenum: 14.000 sequence_1: USE IMAGE ! ! end of exposure logsheet ! No scan data records found