!  File:  1184C.PROP
!  Database:  PEPDB
!  Date:  16-FEB-1994:05:05:53

coverpage:

  title_1:         ULTRAVIOLET ATLAS OF BRIGHT, SUITABLE COMET OF OPPORTUNITY
    sci_cat:       SOLAR SYSTEM
    sci_subcat:    COMETS
    proposal_for:  GTO/HRS
    targ_of_opp:   Y
    pi_fname:      JOHN
    pi_mi:         C.
    pi_lname:      BRANDT
    pi_inst:       LASP-UNIVERSITY OF COLORADO
    pi_country:    USA
    pi_phone:      303-492-3215
    hours_pri:     7.10
    num_pri:       1
    wf_pc:         Y
    fos:           Y
    hrs:           Y
    realtime:      Y
    time_crit:     Y
! end of coverpage

abstract:

    line_1:        This project is a replacement for the Halley's Comet
    line_2:        observations by the HRS outlined in our original proposal.
    line_3:        Our intention is to select a comet of opportunity that is
    line_4:        bright enough to obtain useful observations in the
    line_5:        ultraviolet and that has an orbit which permits
    line_6:        acquisition and tracking by the Space Telescope over an
    line_7:        extended period of time.  The goal is to obtain basically
    line_8:        an HRS atlas concentrating on 20,000 spectral resolution.
    line_9:        The strategy will be to take FOS spectra covering the
    line_10:       entire wavelength region of interest, and then to take HRS
    line_11:       medium and high resolution spectra of specific regions.
    line_12:       The detailed plan for this project depends on the current
    line_13:       capabilities of the HST, and is subject to change.
    line_14:       original limits of GTO time.  This is a priority 1
    line_15:       observing program, cycle TBD.

!
! end of abstract

general_form_proposers:

  lname:           BRANDT
    fname:         JOHN
    title:         PI
    mi:            C.
    inst:          LASP-UNIVERSITY OF COLORADO
    country:       USA

!
! end of general_form_proposers block

general_form_text:

  question:        3
    section:       1
    line_1:        The general approach is as follows.  First FOS spectra with the
    line_2:        high resolution gratings will be taken to cover the spectral range
    line_3:        from 1150 through 3306 A, with moderate S/N.  Then GHRS medium and
    line_4:        high resolution spectra will be taken in various regions of
    line_5:        interest.  One of the main goals will be an extended exposure of
    line_6:        the OH/OD 0-0 transition near 3080 A with echelle B.  A shorter
    line_7:        exposure here using G270M will be obtained to cover the entire OH
    line_8:        0-0 band.  Lyman alpha will be covered with G160M, and various
    line_9:        other transitions will be covered with other medium resolution
    line_10:       gratings.  The target acquisition/tracking procedure is as
    line_11:       follows:  A total of 24 HST orbits will be used, divided into 8
    line_12:       sets of 3 orbits.  It is assumed that each orbit has a total of
    line_13:       52 minutes of charged observing time, bringing the total time for
    line_14:       this proposal to 20.8 hours.  In the first orbit of each set
    line_15:       of 3 orbits we will acquire a real-time image using the
    line_16:       WFC F785LP, putting the cometary nucleus into the apex of
    line_17:       chip 2, which should be the most appropriate position for
    line_18:       subsequent transfer to either the FOS/BL or GHRS.  We will use
    line_19:       the 4.3" FOS aperture and the 2x2" LSA GHRS aperture for the
    line_20:       subsequent observations.  The first two sets of 3 orbits will
    line_21:       be FOS orbits (WFC image followed by 2 FOS orbits), and the next
    line_22:       six sets of 3 orbits will be GHRS orbits (WFC image followed by
    line_23:       2 GHRS orbits).

!

  question:        3
    section:       2
    line_1:        With each WFC image orbit (the first of each set of 3) we will
    line_2:        determine a zero-point ephemeris offset, which will be applied to
    line_3:        both subsequent orbits in the set of 3, in order to center the
    line_4:        nucleus in the FOS (or GHRS) aperture.  The 2nd and 3rd orbits of
    line_5:        the first set of 3 will be identical and will consist of the
    line_6:        following: (1) Guide star acquisition; (2) Uplink of ephemeris
    line_7:        offset to position comet nucleus in 4.3" FOS aperture; (3) FOS
    line_8:        image to confirm positon of target in 4.3" aperture (note that
    line_9:        if the TDRSS link is still open, we may use it to uplink another
    line_10:       offset if the target is poorly centered at this point); (4)
    line_11:       FOS/BL exposure with grating 130H for the remainder of the orbit
    line_12:       observability window.  This exposure is expected to last a
    line_13:       minimum of 16 minutes, yielding 4 spectral readouts of 4-min
    line_14:       exposures.  The second and third orbits of the second set of
    line_15:       3 will be identical to the second and third orbits of the first
    line_16:       set of 3 EXCEPT that in the second orbit of the second set,
    line_17:       grating 190H will be used for the exposure, and in the third
    line_18:       orbit of the second set grating 270H will be used for the
    line_19:       exposure.  The second and third orbits of the 6 remaining sets
    line_20:       of 3 orbits will use the GHRS.  These orbits will consist of
    line_21:       the following: (1) Guide star acquisition; (2) Uplink of
    line_22:       ephemeris offset to position the comet nucleus in the 2x2"
    line_23:       GHRS LSA; (3) GHRS accum exposure for the remainder of the orbit

!

  question:        3
    section:       3
    line_1:        observability window (note that it does not make sense to try to
    line_2:        map the aperture in the UV since the cometary UV profile will be
    line_3:        flat and nuclear position will be poorly defined).  This should
    line_4:        yield approximately 30 minutes of exposure time per orbit
    line_5:        (assuming about 12.5 min for the GS acq and 8.5 min for the
    line_6:        real-time uplink).  The gratings and grating positions used will
    line_7:        depend on the orbit and are delineated below.  The observing plan
    line_8:        is summarized by orbit as:
    line_9:        ORBIT 1: WFC image, F785LP; real-time analysis for ephem. offset.
    line_10:       ORBIT 2: GS acq; Uplink ephem. offset; FOS image; 130H exposure.
    line_11:       ORBIT 3: GS acq; Uplink ephem. offset; FOS image; 130H exposure.
    line_12:       ORBIT 4: WFC image, F785LP; real-time analysis for ephem. offset.
    line_13:       ORBIT 5: GS acq; Uplink ephem. offset; FOS image; 190H exposure.
    line_14:       ORBIT 6: GS acq; Uplink ephem. offset; FOS image; 270H exposure.
    line_15:       ORBIT 7: WFC image, F785LP; real-time analysis for ephem. offset.
    line_16:       ORBIT 8: GS acq; Uplink ephem. offset; HRS Ech-B exp, 3080A.
    line_17:       ORBIT 9: GS acq; Uplink ephem. offset; HRS Ech-B exp, 3080A.
    line_18:       ORBIT 10: WFC image, F785LP; INT ACQ for ephem. offset.
    line_19:       ORBIT 11: GS acq; Uplink ephem. offset; HRS Ech-B exp, 3080A.
    line_20:       ORBIT 12: GS acq; Uplink ephem. offset; HRS Ech-B exp, 3080A.
    line_21:       ORBIT 13: WFC image, F785LP; INT ACQ for ephem. offset.
    line_22:       ORBIT 14: GS acq; Uplink ephem. offset; HRS Ech-B exp, 3080A.
    line_23:       ORBIT 15: GS acq; Uplink ephem. offset; HRS Ech-B exp, 3080A.

!

  question:        3
    section:       4
    line_1:        ORBIT 16: WFC image, F785LP; INT ACQ for ephem. offset.
    line_2:        ORBIT 17: GS acq; Uplink ephem. offset; HRS Ech-B exp, 3080A.
    line_3:        ORBIT 18: GS acq; Uplink ephem. offset; HRS Ech-B, ET=10m,
    line_4:        wave=3085; HRS G160M, ET=20m, wave=1561. (OH, CI)
    line_5:        ORBIT 19: WFC image, F785LP; INT ACQ for ephem. offset.
    line_6:        ORBIT 20: GS acq; Uplink ephem. offset; HRS G270M, ET=5m,
    line_7:        wave=3085; G270M, ET=5m, wave=2576A; G270M, ET=10m, wave=2890A;
    line_8:        G270M, ET=5m, wave=2820; G270M, ET=5m, wave=3142. (OH, CS, CO2+,
    line_9:        OH 1-0, OH 1-1)
    line_10:       ORBIT 21: GS acq; Uplink ephem. offset; HRS G270M, ET=10m,
    line_11:       wave=2321A; HRS G270M, ET=5m, wave=2436A; HRS G270M, ET=15m,
    line_12:       wave=2663; (C2, HI 2nd order, CS)
    line_13:       ORBIT 22: WFC image, F785LP; INT ACQ for ephem. offset.
    line_14:       ORBIT 23: GS acq; Uplink ephem. offset; HRS G200M, ET=10m,
    line_15:       wave=1817A; HRS G200M, ET=20m, wave=2190. (SI, CO+)
    line_16:       ORBIT 24: GS acq; Uplink ephem. offset; HRS G160M, ET=10m,
    line_17:       wave=1216A; HRS G160M, ET=10m, wave=1304A; HRS G160M, ET=10m,
    line_18:       wave=1657A. (Ly-alpha, OI, CI)
    line_19:       Each set of 3 orbits should be performed with a gap of less than
    line_20:       or equal to 1 day before the next set, so that the entire group
    line_21:       of 8 sets (24 orbits) will be executed within the shortest amount
    line_22:       of time possible given the number of RT links available.

!

  question:        3
    section:       5
    line_1:        The sequences described above assume there will be suitable guide
    line_2:        stars available in each orbit, from which we can switch to gyro
    line_3:        control if the guide star pair is lost due to cometary motion.
    line_4:        However, we have also defined an alternate sequence to be used if
    line_5:        siutable guide stars are not available.  This sequence is referred
    line_6:        to as a dummy sequence.  In this case, each logsheet line will be
    line_7:        preceded by a dummy guide star acquisition using a nearby fixed
    line_8:        target.  This will enable us to transfer to gyro control for the
    line_9:        subsequent comet observations.  This will cost an additional
    line_10:       amount of time during each orbit due to the slew time necessary
    line_11:       for transfer from the dummy target to the comet.  The general
    line_12:       procedure described above also assumes that HST will not have
    line_13:       guide star hand-off capabilities. If this capability is available
    line_14:       we will use the hand-offs rather than proceeding to gyro control.
    line_15:       In this case, each FOS orbit or GHRS orbit (the 2 orbits
    line_16:       subsequent to the orbit in which the WFC image is taken) will
    line_17:       begin with a guide star RE-acquisition, rather than a guide star
    line_18:       acq.  With the time saved during the re-acq, we will subsequently
    line_19:       perform an onboard acq to center the comet in the 4.3 arcsec
    line_20:       aperture if it is an FOS orbit, or increase exposure times if
    line_21:       it is a GHRS orbit.
    line_22:       NOTE ADDED BY SPB:  DUMMY exposures were found not to be
    line_23:       necessary, and were removed.

!

  question:        4
    section:       1
    line_1:        This program requires high sensitivity and high UV spectral
    line_2:        resolution observations of a diffuse cometary source.  Only
    line_3:        HST has these capabilities.

!

  question:        5
    section:       1
    line_1:        These observations are to be made on an unknown comet of
    line_2:        opportunity.  A real time uplink will be needed to
    line_3:        position the spectrograph apertures at a known, appropriate
    line_4:        position on the comet to ensure sufficient signal and allow a
    line_5:        clear interpretation of the results.  Comet must be observed at
    line_6:        specific positions in its orbit, hence the science observations
    line_7:        are time critical.

!

  question:        6
    section:       1
    line_1:        N/A.

!

  question:        7
    section:       1
    line_1:        Observations will be reduced using the facilities of the
    line_2:        Laboratory for Atmospheric and Space Physics and software
    line_3:        developed by the GHRS IDT.

!

  question:        8
    section:       1
    line_1:        As per previous agreement with STScI, the time allocated to
    line_2:        this program may be utilized after the end of the GTO period if
    line_3:        no suitable comet of opportunity appears during the GTO period.

!

  question:        9
    section:       1
    line_1:        The only previous HST data were for the GHRS team project on
    line_2:        the quasar 3C 273, and for science verification tests, none of
    line_3:        which are related to this proposal.

!

  question:        10
    section:       1
    line_1:        VAX computer, IBM-compatible PC, Image display device,
    line_2:        Graduate students, Data reduction software (from HRS IDT).

!
!end of general form text

general_form_address:

  lname:           BRANDT
    fname:         JOHN
    mi:            C.
    category:      PI
    inst:          UNIVERSITY OF COLORADO
    addr_1:        UNIVERSITY OF COLORADO
    addr_2:        LABORATORY FOR ATMOSPHERIC
    addr_3:        AND SPACE PHYSICS, CB 392
    city:          BOULDER
    state:         CO
    zip:           80309
    country:       USA
    phone:         303 492 3215

!
! end of general_form_address records

! No fixed target records found

solar_system_targets:

  targnum:         1
    name_1:        COMET
    descr_1:       COMET OF-OPORTUNITY
    lev1_1:        TYPE = COMET,
    lev1_2:        Q = 1.202158, E = 0.704849,
    lev1_3:        O = 81.0530, W = 57.4820,
    lev1_4:        I = 11.8458,
    lev1_5:        T = 03-MAR-93:23:03:33,
    lev1_6:        EQUINOX = J2000,
    lev1_7:        EPOCH = 22-FEB-93, ACQ = 0.25
    comment_1:     GENERIC COMET, FILL IN ACTUAL
    comment_2:     VALUES WHEN AN OPORTUNISTIC
    comment_3:     COMET PRESENTS ITSELF
    fluxnum_1:     1
    fluxval_1:     SURF(V) = 14 +/- 1
    fluxnum_2:     2
    fluxval_2:     SURF-LINE(4315) = 2.5 +/- 1.2 E-14
    fluxnum_3:     3
    fluxval_3:     W-LINE(4315) = 0.029
    fluxnum_4:     4
    fluxval_4:     SURF-LINE(5730) = 2 +/- 1 E-14
    fluxnum_5:     5
    fluxval_5:     W-LINE(5730) = 0.038
    fluxnum_6:     6
    fluxval_6:     SURF-LINE(1478) = 2 +/- 1 E-13
    fluxnum_7:     7
    fluxval_7:     W-LINE(1478) = 0.0099
    fluxnum_8:     8
    fluxval_8:     SURF-LINE(2957) = 1.5 +/- 0.7 E-13
    fluxnum_9:     9
    fluxval_9:     W-LINE(2957) = 0.020
    fluxnum_10:    10
    fluxval_10:    SIZE = 1

!
! end of solar system targets

! No generic target records found

exposure_logsheet:

    linenum:       10.000
    sequence_1:    DEF
    sequence_2:    ACQ-WFC
    targname:      #
    config:        WFC
    opmode:        IMAGE
    aperture:      WF2
    sp_element:    F785LP
    num_exp:       1
    time_per_exp:  5.0 S
    priority:      1
    req_1:         POS TARG -10, +20
    comment_1:     WFC IMAGE TO OBTAIN ZERO-PT
    comment_2:     EPHEMERIS OFFSET. TARGET IN
    comment_3:     CHIP 2 APEX. INTERACTIVE ACQ,
    comment_4:     REQUIRES INT ACQ.  EXP
    comment_5:     MAY CHANGE DEPENDING ON
    comment_6:     BRIGHTNESS OF COMET.

!

    linenum:       20.000
    sequence_1:    DEF
    sequence_2:    ACQ-FOS
    targname:      #
    config:        FOS/BL
    opmode:        ACQ/BINARY
    aperture:      4.3
    sp_element:    MIRROR
    num_exp:       1
    time_per_exp:  1 S
    priority:      1
    comment_1:     ONBOARD ACQ TO BE USED
    comment_2:     IF GS HANDOFFS AVAILABLE.

!

    linenum:       30.000
    sequence_1:    DEF
    sequence_2:    IMAGE-FOS
    targname:      #
    config:        FOS/BL
    opmode:        ACQ
    aperture:      4.3
    sp_element:    MIRROR
    num_exp:       1
    time_per_exp:  1 S
    priority:      1
    comment_1:     IMAGE OF APERTURE TO CONFIRM
    comment_2:     TARGET POSITION.

!

    linenum:       31.000
    sequence_1:    DEF
    sequence_2:    IMAGE-FOS1
    targname:      #
    config:        FOS/BL
    opmode:        ACQ
    aperture:      4.3
    sp_element:    MIRROR
    num_exp:       1
    time_per_exp:  1 S
    priority:      1
    comment_1:     IMAGE OF APERTURE TO CONFIRM
    comment_2:     TARGET POSITION.

!

    linenum:       40.000
    sequence_1:    DEF
    sequence_2:    FOS-130
    targname:      #
    config:        FOS/BL
    opmode:        ACCUM
    aperture:      4.3
    sp_element:    G130H
    num_exp:       1
    time_per_exp:  16M
    priority:      1
    comment_1:     EXPOSE FOR AS MUCH TIME
    comment_2:     AS IS LEFT IN ORBIT AFTER
    comment_3:     GS ACQ AND FOS IMAGE. IF GS PAIR
    comment_4:     IS LOST, SWITCH TO GYROS. ASSUMES
    comment_5:     52-MINUTE OBSERVING WINDOW.

!

    linenum:       50.000
    sequence_1:    DEF
    sequence_2:    FOS-190
    targname:      #
    config:        FOS/BL
    opmode:        ACCUM
    aperture:      4.3
    sp_element:    G190H
    num_exp:       1
    time_per_exp:  16M
    priority:      1
    comment_1:     EXPOSE FOR AS MUCH TIME
    comment_2:     AS IS LEFT IN ORBIT AFTER
    comment_3:     GS ACQ AND FOS IMAGE. IF GS PAIR
    comment_4:     IS LOST, SWITCH TO GYROS. ASSUMES
    comment_5:     52-MINUTE OBSERVING WINDOW.

!

    linenum:       60.000
    sequence_1:    DEF
    sequence_2:    FOS-270
    targname:      #
    config:        FOS/BL
    opmode:        ACCUM
    aperture:      4.3
    sp_element:    G270H
    num_exp:       1
    time_per_exp:  16M
    priority:      1
    comment_1:     EXPOSE FOR AS MUCH TIME
    comment_2:     AS IS LEFT IN ORBIT AFTER
    comment_3:     GS ACQ AND FOS IMAGE. IF GS PAIR
    comment_4:     IS LOST, SWITCH TO GYROS. ASSUMES
    comment_5:     52-MINUTE OBSERVING WINDOW.

!

    linenum:       70.000
    sequence_1:    DEF
    sequence_2:    HRS-OD
    targname:      #
    config:        HRS
    opmode:        ACCUM
    aperture:      2.0
    sp_element:    ECH-B
    wavelength:    3079
    num_exp:       3
    time_per_exp:  10 M
    fluxnum_1:     2
    priority:      1
    param_1:       FP-SPLIT=STD
    comment_1:     SWITCH TO GYROS IF GS LOST.
    comment_2:     EXPOSE AFTER GS ACQ AND
    comment_3:     EPHEMERIS OFFSET UPLINK.
    comment_4:     ASSUMES 52-MINUTE OBSERVING
    comment_5:     WINDOW, 12.5M FOR GS ACQ AND
    comment_6:     8.5M FOR UPLINK.

!

    linenum:       80.000
    sequence_1:    DEF
    sequence_2:    HRS-O18
    targname:      #
    config:        HRS
    opmode:        ACCUM
    aperture:      2.0
    sp_element:    ECH-B
    wavelength:    3085
    num_exp:       1
    time_per_exp:  10 M
    s_to_n:        100
    fluxnum_1:     3
    priority:      1
    param_1:       FP-SPLIT=STD
    comment_1:     SWITCH TO GYROS IF GS LOST.
    comment_2:     EXPOSE AFTER GS ACQ AND
    comment_3:     EPHEMERIS OFFSET UPLINK.
    comment_4:     ORBIT 18.

!

    linenum:       90.000
    sequence_1:    DEF
    sequence_2:    HRS-O18
    targname:      #
    config:        HRS
    opmode:        ACCUM
    aperture:      2.0
    sp_element:    G160M
    wavelength:    1561
    num_exp:       2
    time_per_exp:  10 M
    s_to_n:        6
    fluxnum_1:     4
    priority:      1
    param_1:       FP-SPLIT=STD
    comment_1:     SWITCH TO GYROS IF GS LOST.
    comment_2:     EXPOSE AFTER GS ACQ AND
    comment_3:     EPHEMERIS OFFSET UPLINK.
    comment_4:     ORBIT 18.

!

    linenum:       100.000
    sequence_1:    DEF
    sequence_2:    HRS-O20
    targname:      #
    config:        HRS
    opmode:        ACCUM
    aperture:      2.0
    sp_element:    G270M
    wavelength:    3085
    num_exp:       1
    time_per_exp:  5 M
    s_to_n:        100
    fluxnum_1:     3
    priority:      1
    param_1:       FP-SPLIT=STD
    comment_1:     SWITCH TO GYROS IF GS LOST.
    comment_2:     EXPOSE AFTER GS ACQ AND
    comment_3:     EPHEMERIS OFFSET UPLINK.
    comment_4:     ORBIT 20.

!

    linenum:       110.000
    sequence_1:    DEF
    sequence_2:    HRS-O20
    targname:      #
    config:        HRS
    opmode:        ACCUM
    aperture:      2.0
    sp_element:    G270M
    wavelength:    2576
    num_exp:       1
    time_per_exp:  5 M
    s_to_n:        10
    fluxnum_1:     5
    priority:      1
    param_1:       FP-SPLIT=STD
    comment_1:     SWITCH TO GYROS IF GS LOST.
    comment_2:     EXPOSE AFTER GS ACQ AND
    comment_3:     EPHEMERIS OFFSET UPLINK.
    comment_4:     ORBIT 20.

!

    linenum:       120.000
    sequence_1:    DEF
    sequence_2:    HRS-O20
    targname:      #
    config:        HRS
    opmode:        ACCUM
    aperture:      2.0
    sp_element:    G270M
    wavelength:    2890
    num_exp:       1
    time_per_exp:  10 M
    s_to_n:        10
    fluxnum_1:     6
    priority:      1
    param_1:       FP-SPLIT=STD
    comment_1:     SWITCH TO GYROS IF GS LOST.
    comment_2:     EXPOSE AFTER GS ACQ AND
    comment_3:     EPHEMERIS OFFSET UPLINK.
    comment_4:     ORBIT 20.

!

    linenum:       130.000
    sequence_1:    DEF
    sequence_2:    HRS-O20
    targname:      #
    config:        HRS
    opmode:        ACCUM
    aperture:      2.0
    sp_element:    G270M
    wavelength:    2820
    num_exp:       1
    time_per_exp:  5 M
    s_to_n:        30
    fluxnum_1:     7
    priority:      1
    param_1:       FP-SPLIT=STD
    comment_1:     SWITCH TO GYROS IF GS LOST.
    comment_2:     EXPOSE AFTER GS ACQ AND
    comment_3:     EPHEMERIS OFFSET UPLINK.
    comment_4:     ORBIT 20.

!

    linenum:       140.000
    sequence_1:    DEF
    sequence_2:    HRS-O20
    targname:      #
    config:        HRS
    opmode:        ACCUM
    aperture:      2.0
    sp_element:    G270M
    wavelength:    3142
    num_exp:       1
    time_per_exp:  5 M
    s_to_n:        15
    fluxnum_1:     8
    priority:      1
    param_1:       FP-SPLIT=STD
    comment_1:     SWITCH TO GYROS IF GS LOST.
    comment_2:     EXPOSE AFTER GS ACQ AND
    comment_3:     EPHEMERIS OFFSET UPLINK.
    comment_4:     ORBIT 20.

!

    linenum:       150.000
    sequence_1:    DEF
    sequence_2:    HRS-O21
    targname:      #
    config:        HRS
    opmode:        ACCUM
    aperture:      2.0
    sp_element:    G270M
    wavelength:    2321
    num_exp:       1
    time_per_exp:  10 M
    s_to_n:        6
    fluxnum_1:     9
    priority:      1
    param_1:       FP-SPLIT=STD
    comment_1:     SWITCH TO GYROS IF GS LOST.
    comment_2:     EXPOSE AFTER GS ACQ AND
    comment_3:     EPHEMERIS OFFSET UPLINK.
    comment_4:     ORBIT 21.

!

    linenum:       160.000
    sequence_1:    DEF
    sequence_2:    HRS-O21
    targname:      #
    config:        HRS
    opmode:        ACCUM
    aperture:      2.0
    sp_element:    G270M
    wavelength:    2436
    num_exp:       1
    time_per_exp:  5 M
    s_to_n:        8
    priority:      1
    param_1:       FP-SPLIT=STD
    comment_1:     SWITCH TO GYROS IF GS LOST.
    comment_2:     EXPOSE AFTER GS ACQ AND
    comment_3:     EPHEMERIS OFFSET UPLINK.
    comment_4:     ORBIT 21.

!

    linenum:       170.000
    sequence_1:    DEF
    sequence_2:    HRS-O21
    targname:      #
    config:        HRS
    opmode:        ACCUM
    aperture:      2.0
    sp_element:    G270M
    wavelength:    2663
    num_exp:       2
    time_per_exp:  7.5 M
    s_to_n:        6
    priority:      1
    param_1:       FP-SPLIT=STD
    comment_1:     SWITCH TO GYROS IF GS LOST.
    comment_2:     EXPOSE AFTER GS ACQ AND
    comment_3:     EPHEMERIS OFFSET UPLINK.
    comment_4:     ORBIT 21.

!

    linenum:       180.000
    sequence_1:    DEF
    sequence_2:    HRS-O23
    targname:      #
    config:        HRS
    opmode:        ACCUM
    aperture:      2.0
    sp_element:    G200M
    wavelength:    1817
    num_exp:       1
    time_per_exp:  10 M
    s_to_n:        9
    priority:      1
    param_1:       FP-SPLIT=STD
    comment_1:     SWITCH TO GYROS IF GS LOST.
    comment_2:     EXPOSE AFTER GS ACQ AND
    comment_3:     EPHEMERIS OFFSET UPLINK.
    comment_4:     ORBIT 23.

!

    linenum:       190.000
    sequence_1:    DEF
    sequence_2:    HRS-O23
    targname:      #
    config:        HRS
    opmode:        ACCUM
    aperture:      2.0
    sp_element:    G200M
    wavelength:    2190
    num_exp:       2
    time_per_exp:  10 M
    s_to_n:        5
    priority:      1
    param_1:       FP-SPLIT=STD
    comment_1:     SWITCH TO GYROS IF GS LOST.
    comment_2:     EXPOSE AFTER GS ACQ AND
    comment_3:     EPHEMERIS OFFSET UPLINK.
    comment_4:     ORBIT 23.

!

    linenum:       200.000
    sequence_1:    DEF
    sequence_2:    HRS-O24
    targname:      #
    config:        HRS
    opmode:        ACCUM
    aperture:      2.0
    sp_element:    G160M
    wavelength:    1216
    num_exp:       2
    time_per_exp:  5 M
    s_to_n:        100
    priority:      1
    param_1:       FP-SPLIT=STD
    comment_1:     SWITCH TO GYROS IF GS LOST.
    comment_2:     EXPOSE AFTER GS ACQ AND
    comment_3:     EPHEMERIS OFFSET UPLINK.
    comment_4:     ORBIT 24.

!

    linenum:       203.000
    sequence_1:    DEF
    sequence_2:    HRS-O24
    targname:      #
    config:        HRS
    opmode:        ACCUM
    aperture:      2.0
    sp_element:    G160M
    wavelength:    1304
    num_exp:       1
    time_per_exp:  10 M
    s_to_n:        12
    priority:      1
    param_1:       FP-SPLIT=STD
    comment_1:     SWITCH TO GYROS IF GS LOST.
    comment_2:     EXPOSE AFTER GS ACQ AND
    comment_3:     EPHEMERIS OFFSET UPLINK.
    comment_4:     ORBIT 24.

!

    linenum:       204.000
    sequence_1:    DEF
    sequence_2:    HRS-O24
    targname:      #
    config:        HRS
    opmode:        ACCUM
    aperture:      2.0
    sp_element:    G160M
    wavelength:    1657
    num_exp:       1
    time_per_exp:  10 M
    s_to_n:        12
    priority:      1
    param_1:       FP-SPLIT=STD
    comment_1:     SWITCH TO GYROS IF GS LOST.
    comment_2:     EXPOSE AFTER GS ACQ AND
    comment_3:     EPHEMERIS OFFSET UPLINK.
    comment_4:     ORBIT 24.

!

    linenum:       205.000
    sequence_1:    USE
    sequence_2:    ACQ-WFC
    targname:      COMET
    req_1:         INT ACQ FOR 215-225;
    req_2:         SEQ 205-225 NO GAP;
    req_3:         SELECT 1 OF 205-250 OR 255-300;
    req_4:         COND IF M2 < 9.8 / 205-250;
    req_5:         CRIT OBS / 205-250;
    req_6:         CYCLE 2  / 205-250;
    req_7:         GUIDE TOL 0.6" / 205-250;
    comment_1:     WFC IMAGE TO GET ZERO-PT EPHEMERIS
    comment_2:     FOR NEXT TWO OFFSET. INT-ACQ
    comment_3:     ORBITS IN WHICH FOS MAP AND
    comment_4:     ACCUMS TAKEN. THIS IS 1ST ORBIT.
    comment_5:     SELECT THIS SET IF NUCLEAR
    comment_6:     MAG BRIGHTER THAN 9.8.

!

    linenum:       215.000
    sequence_1:    USE
    sequence_2:    FOS-130
    targname:      COMET
    req_1:         REQ UPLINK;
    comment_1:     SPECTRAL EXPOSURE FOR
    comment_2:     2ND ORBIT.

!

    linenum:       225.000
    sequence_1:    USE
    sequence_2:    FOS-130
    targname:      COMET
    req_1:         REQ UPLINK;
    comment_1:     SPECTRAL EXPOSURE FOR
    comment_2:     3RD ORBIT.

!

    linenum:       230.000
    sequence_1:    USE
    sequence_2:    ACQ-WFC
    targname:      COMET
    req_1:         INT ACQ FOR 240-250;
    req_2:         SEQ 230-250 NO GAP
    comment_1:     WFC IMAGE TO GET ZERO-PT
    comment_2:     EPHEMERIS OFFSET. INT-ACQ
    comment_3:     FOR NEXT TWO ORBITS IN
    comment_4:     WHICH FOS MAP AND ACCUMS
    comment_5:     TAKEN. THIS IS 4TH ORBIT.

!

    linenum:       240.000
    sequence_1:    USE
    sequence_2:    FOS-190
    targname:      COMET
    req_1:         REQ UPLINK;
    comment_1:     SPECTRAL EXPOSURE FOR
    comment_2:     5TH ORBIT.

!

    linenum:       250.000
    sequence_1:    USE
    sequence_2:    FOS-270
    targname:      COMET
    req_1:         REQ UPLINK;
    comment_1:     SPECTRAL EXPOSURE FOR
    comment_2:     6TH ORBIT.

!

    linenum:       255.000
    sequence_1:    USE
    sequence_2:    ACQ-WFC
    targname:      COMET
    req_1:         INT ACQ FOR 260-275;
    req_2:         SEQ 255-275 NO GAP;
    req_3:         CRIT OBS / 255-300;
    req_4:         CYCLE 2  / 255-300;
    req_5:         GUIDE TOL 0.6" / 255-300;
    req_6:         COND IF M2 > 9.8 / 255-300;
    comment_1:     WFC IMAGE TO GET ZERO-PT EPHEMERIS
    comment_2:     FOR NEXT TWO OFFSET. INT-ACQ
    comment_3:     ORBITS IN WHICH FOS MAP AND
    comment_4:     ACCUMS TAKEN. THIS IS 1ST ORBIT.
    comment_5:     SELECT THIS SET IF NUCLEAR
    comment_6:     MAG FAINTER THAN 9.8.

!

    linenum:       260.000
    sequence_1:    USE
    sequence_2:    IMAGE-FOS
    targname:      COMET
    req_1:         REQ UPLINK;
    req_2:         SEQ 260-265 NON-INT
    comment_1:     FOS APERTURE MAP FOR
    comment_2:     2ND ORBIT

!

    linenum:       265.000
    sequence_1:    USE
    sequence_2:    FOS-130
    targname:      COMET
    comment_1:     SPECTRAL EXPOSURE FOR
    comment_2:     2ND ORBIT.

!

    linenum:       270.000
    sequence_1:    USE
    sequence_2:    IMAGE-FOS1
    targname:      COMET
    req_1:         REQ UPLINK;
    req_2:         SEQ 270-275 NON-INT
    comment_1:     FOS APERTURE MAP FOR
    comment_2:     3RD ORBIT

!

    linenum:       275.000
    sequence_1:    USE
    sequence_2:    FOS-130
    targname:      COMET
    comment_1:     SPECTRAL EXPOSURE FOR
    comment_2:     3RD ORBIT.

!

    linenum:       280.000
    sequence_1:    USE
    sequence_2:    ACQ-WFC
    targname:      COMET
    req_1:         INT ACQ FOR 285-300;
    req_2:         SEQ 280-300 NO GAP
    comment_1:     WFC IMAGE TO GET ZERO-PT
    comment_2:     EPHEMERIS OFFSET. INT-ACQ
    comment_3:     FOR NEXT TWO ORBITS IN
    comment_4:     WHICH FOS MAP AND ACCUMS
    comment_5:     TAKEN. THIS IS 4TH ORBIT.

!

    linenum:       285.000
    sequence_1:    USE
    sequence_2:    IMAGE-FOS
    targname:      COMET
    req_1:         REQ UPLINK;
    req_2:         SEQ 285-290 NON-INT
    comment_1:     FOS APERTURE MAP FOR
    comment_2:     5TH ORBIT

!

    linenum:       290.000
    sequence_1:    USE
    sequence_2:    FOS-190
    targname:      COMET
    comment_1:     SPECTRAL EXPOSURE FOR
    comment_2:     5TH ORBIT.

!

    linenum:       295.000
    sequence_1:    USE
    sequence_2:    IMAGE-FOS1
    targname:      COMET
    req_1:         REQ UPLINK;
    req_2:         SEQ 295-300 NON-INT
    comment_1:     FOS APERTURE MAP FOR
    comment_2:     6TH ORBIT

!

    linenum:       300.000
    sequence_1:    USE
    sequence_2:    FOS-270
    targname:      COMET
    comment_1:     SPECTRAL EXPOSURE FOR
    comment_2:     6TH ORBIT.

!

    linenum:       310.000
    sequence_1:    USE
    sequence_2:    ACQ-WFC
    targname:      COMET
    req_1:         INT ACQ FOR 320-330;
    req_2:         SEQ 310-330 NO GAP;
    req_3:         CRIT OBS / 310-480;
    req_4:         GUIDE TOL 0.6" / 310-480;
    req_6:         CYCLE 2  / 310-480;
    comment_1:     WFC IMAGE TO GET ZERO-PT
    comment_2:     EPHEMERIS OFFSET. INT-ACQ
    comment_3:     FOR NEXT TWO ORBITS IN
    comment_4:     WHICH GHRS ACCUMS TAKEN.
    comment_5:     THIS IS 7TH ORBIT.

!

    linenum:       320.000
    sequence_1:    USE
    sequence_2:    HRS-OD
    targname:      COMET
    req_1:         REQ UPLINK;
    comment_1:     SPECTRAL EXPOSURE FOR
    comment_2:     8TH ORBIT. DONE AFTER
    comment_3:     GS ACQ AND UPLINK.

!

    linenum:       330.000
    sequence_1:    USE
    sequence_2:    HRS-OD
    targname:      COMET
    req_1:         REQ UPLINK;
    comment_1:     SPECTRAL EXPOSURE FOR
    comment_2:     9TH ORBIT. DONE AFTER
    comment_3:     GS ACQ AND UPLINK.

!

    linenum:       340.000
    sequence_1:    USE
    sequence_2:    ACQ-WFC
    targname:      COMET
    req_1:         INT ACQ FOR 350-360;
    req_2:         SEQ 340-360 NO GAP
    comment_1:     WFC IMAGE TO GET ZERO-PT
    comment_2:     EPHEMERIS OFFSET. INT-ACQ
    comment_3:     FOR NEXT TWO ORBITS IN
    comment_4:     WHICH GHRS ACCUMS TAKEN.
    comment_5:     THIS IS 10TH ORBIT.

!

    linenum:       350.000
    sequence_1:    USE
    sequence_2:    HRS-OD
    targname:      COMET
    req_1:         REQ UPLINK;
    comment_1:     SPECTRAL EXPOSURE FOR
    comment_2:     11TH ORBIT. DONE AFTER
    comment_3:     GS ACQ AND UPLINK.

!

    linenum:       360.000
    sequence_1:    USE
    sequence_2:    HRS-OD
    targname:      COMET
    req_1:         REQ UPLINK;
    comment_1:     SPECTRAL EXPOSURE FOR
    comment_2:     12TH ORBIT. DONE AFTER
    comment_3:     GS ACQ AND UPLINK.

!

    linenum:       370.000
    sequence_1:    USE
    sequence_2:    ACQ-WFC
    targname:      COMET
    req_1:         INT ACQ FOR 380-390;
    req_2:         SEQ 370-390 NO GAP
    comment_1:     WFC IMAGE TO GET ZERO-PT
    comment_2:     EPHEMERIS OFFSET. INT-ACQ
    comment_3:     FOR NEXT TWO ORBITS IN
    comment_4:     WHICH GHRS ACCUMS TAKEN.
    comment_5:     THIS IS 13TH ORBIT.

!

    linenum:       380.000
    sequence_1:    USE
    sequence_2:    HRS-OD
    targname:      COMET
    req_1:         REQ UPLINK;
    comment_1:     SPECTRAL EXPOSURE FOR
    comment_2:     14TH ORBIT. DONE AFTER
    comment_3:     GS ACQ AND UPLINK.

!

    linenum:       390.000
    sequence_1:    USE
    sequence_2:    HRS-OD
    targname:      COMET
    req_1:         REQ UPLINK;
    comment_1:     SPECTRAL EXPOSURE FOR
    comment_2:     15TH ORBIT. DONE AFTER
    comment_3:     GS ACQ AND UPLINK.

!

    linenum:       400.000
    sequence_1:    USE
    sequence_2:    ACQ-WFC
    targname:      COMET
    req_1:         INT ACQ FOR 410-420;
    req_2:         SEQ 400-420 NO GAP
    comment_1:     WFC IMAGE TO GET ZERO-PT
    comment_2:     EPHEMERIS OFFSET. INT-ACQ
    comment_3:     FOR NEXT TWO ORBITS IN
    comment_4:     WHICH GHRS ACCUMS TAKEN.
    comment_5:     THIS IS 16TH ORBIT.

!

    linenum:       410.000
    sequence_1:    USE
    sequence_2:    HRS-OD
    targname:      COMET
    req_1:         REQ UPLINK;
    comment_1:     SPECTRAL EXPOSURE FOR
    comment_2:     17TH ORBIT. DONE AFTER
    comment_3:     GS ACQ AND UPLINK.

!

    linenum:       420.000
    sequence_1:    USE
    sequence_2:    HRS-O18
    targname:      COMET
    req_1:         REQ UPLINK;
    comment_1:     SPECTRAL EXPOSURES FOR
    comment_2:     18TH ORBIT. DONE AFTER
    comment_3:     GS ACQ AND UPLINK.

!

    linenum:       430.000
    sequence_1:    USE
    sequence_2:    ACQ-WFC
    targname:      COMET
    req_1:         INT ACQ FOR 440-450;
    req_2:         SEQ 430-450 NO GAP
    comment_1:     WFC IMAGE TO GET ZERO-PT
    comment_2:     EPHEMERIS OFFSET. INT-ACQ
    comment_3:     FOR NEXT TWO ORBITS IN
    comment_4:     WHICH GHRS ACCUMS TAKEN.
    comment_5:     THIS IS 19TH ORBIT.

!

    linenum:       440.000
    sequence_1:    USE
    sequence_2:    HRS-O20
    targname:      COMET
    req_1:         REQ UPLINK;
    comment_1:     SPECTRAL EXPOSURES FOR
    comment_2:     20TH ORBIT. DONE AFTER
    comment_3:     GS ACQ AND UPLINK.

!

    linenum:       450.000
    sequence_1:    USE
    sequence_2:    HRS-O21
    targname:      COMET
    req_1:         REQ UPLINK;
    comment_1:     SPECTRAL EXPOSURES FOR
    comment_2:     21TH ORBIT. DONE AFTER
    comment_3:     GS ACQ AND UPLINK.

!

    linenum:       460.000
    sequence_1:    USE
    sequence_2:    ACQ-WFC
    targname:      COMET
    req_1:         INT ACQ FOR 470-480;
    req_2:         SEQ 460-480 NO GAP
    comment_1:     WFC IMAGE TO GET ZERO-PT
    comment_2:     EPHEMERIS OFFSET. INT-ACQ
    comment_3:     FOR NEXT TWO ORBITS IN
    comment_4:     WHICH GHRS ACCUMS TAKEN.
    comment_5:     THIS IS 22ND ORBIT.

!

    linenum:       470.000
    sequence_1:    USE
    sequence_2:    HRS-O23
    targname:      COMET
    req_1:         REQ UPLINK;
    comment_1:     SPECTRAL EXPOSURE FOR
    comment_2:     23RD ORBIT. DONE AFTER
    comment_3:     GS ACQ AND UPLINK.

!

    linenum:       480.000
    sequence_1:    USE
    sequence_2:    HRS-O24
    targname:      COMET
    req_1:         REQ UPLINK;
    comment_1:     SPECTRAL EXPOSURE FOR
    comment_2:     24TH ORBIT. DONE AFTER
    comment_3:     GS ACQ AND UPLINK.

!
! end of exposure logsheet

! No scan data records found