! 6697.prop 
! Ray Lucas - 10 July, 1996
!
! Modifications as of 10 July, 1996 consisted of the following:
! - Added GS Plate-ID=0688 to Target #1 since it was the only GS plate from
!   which the guide stars used to make the FOC observations could have come.
!   ( The coords were near the middle of the GS Plate, and there was no other
!   special plate for that field, so no part of the FOC or FGS fields of view
!   could fall into a GS plate overlap region for either the FOC or the FOS
!   observations. ) This determination about the GS Plate ID was made by Ray
!   Lucas using the GSSS Plate database, and Conrad Sturch verified that there
!   was no other special plate used for this globular cluster in the GSC.
! - Removed references to Plate epoch since addition of GS Plate ID fixes all 
!   problems related to that by virtue of the fact that the 1994 observations
!   and positions were made based on the GS reference frame of the plate used
!   to provide GSs for that observation, which was in fact the following:
!   Equinox J2000.0/Epoch 1987.70
!   and which is by definition also the reference frame which will be used for
!   the GSs and pointing/target position for the FOS observations since the 
!   GS Plate ID 0688 ( XV181 ) is the only one which can be used for GSs.
! - Added comments to Target #1 comments explaining the above changes.
! - Added info about GS star IDs used to make the FOC observations and taken
!   by Ray Lucas from the .shh file ( x2g10101t.shh ) for those observations.
!   This info was added to the Visit comments for Visit 01.
! - Updated Texp for Stages 1-3 ( Exp Log lines 1-3 ) in Visit 01 as per the
!   Contact Scientist review from Michael Dahlem.
! Made the following change on 16 July, 1996 - RAL
! - Changed aperture to 0.5 in Exp Log line 24 as per Rex Saffer's email.
!
! Proposal 6697, submission 1
! PI: Guido De Marchi
! Received Tue Feb 20 20:25:22 EST 1996
! From: saffer@stsci.edu
Proposal_Information                           ! Section 4
              Title:  The Blue Stragglers in the Core of NGC
                      6397
  Proposal_Category:  GO
Scientific_Category:  HOT STARS
             Cycle:    6

Investigators
     PI_name:         Guido De Marchi
     PI_Institution:  Space Telescope Science Institute

          CoI_Name:   Mario Livio
   CoI_Institution:   Space Telescope Science Institute
           Contact:             ! Y or N (designate at most one contact)

          CoI_Name:   Dante Minniti
   CoI_Institution:   European Southern Observatory
           Contact:             ! Y or N (designate at most one contact)

          CoI_Name:   Nino Panagia
   CoI_Institution:   Space Telescope Science Institute
           Contact:             ! Y or N (designate at most one contact)

          CoI_Name:   Francesco Paresce
   CoI_Institution:   European Southern Observatory
           Contact:             ! Y or N (designate at most one contact)

          CoI_Name:   Rex Saffer
   CoI_Institution:   Space Telescope Science Institute
           Contact:   Y          ! Y or N (designate at most one contact)


Abstract:                                ! Free format text (please update)
    Six bright blue stragglers dominate the core of the globular
    cluster NGC 6397. They are the most massive objects detected
    in this cluster. No other blue stragglers are found within one
    core radius of the cluster center, and although a total of 26
    blue stragglers are known in NGC 6397, none of them is as
    bright as the six objects in the core. Photometric data and
    low resolution spectroscopy that we obtained with the HST in
    the UV classify them in the late-B to mid-A spectral type
    range. Although a merger of two stars is likely to have given
    birth to these stars (in view of their mass, estimated
    photometrically), no direct indication exists on their
    formation mechanism: both hypotheses of a binary merger (in
    which stars in full contact evolve into coalescence after mass
    transfer) as well as coalescence following a collision are
    compatible with the available data. We, therefore, propose to
    obtain medium resolution FOS spectra to investigate the nature
    of these objects. From the spectral analysis of the Balmer
    jump and Balmer line profiles and from the known UV colors, we
    will be able to determine T(eff)\ and \logg. Knowing the
    distance to the cluster, masses will accurately be determined
    for the first time, and will allow us to assess more reliably
    the formation mechanism. To better understand their
    evolutionary scenario, we will also compare their photospheric
    He abundances (higher after a collision) and rotational
    velocities (higher in a merged binary) with those of a blue
    horizontal branch star near the core.

Questions                       ! Free format text (please update)

     Observing_Description:
         NOTE: The original observing description below mentions the
         0.3 aperture as the aperture of choice, but this has been 
         modified after further discussions between the Contact Scientist
         and the observers.  
         
         Original text:
         We propose to obtain optical (G400H, G570H) spectra through
         the 0.26"\ ( 0.3) circular aperture of six very blue and
         bright blue stragglers (BSS) in the core of NGC 6397. We have
         performed simulations, analysing synthetic spectra to which
         noise has been added, showing that with a signal-to-noise
         ratio (S/N) of 30, precise estimates of the atmospheric
         parameters T(eff)\ and \logg\ can be made (DeltaT(eff)\ ~ 500
         K, Delta\logg\ ~ 0.1 dex). Saffer (1991) has shown
         convincingly that despite the correlation of effective
         temperature and surface gravity errors, the internal error
         estimates (precision) agree well with external estimates
         based on repeated observations of standard stars. Further,
         for a subsample of bright, well-studied objects analyzed by
         Saffer et al. (1994), the zero points (accuracy) also agree
         well with temperature and gravity determinations based on a
         variety of independent analysis techniques in the literature.
         The random and systematic errors associated with the proposed
         analysis thus are shown to be well understood, and the error
         estimates cited above are reliable. Combined with the
         distance to NGC 6397, the temperature and gravity
         determinations will allow mass estimates to within ~ 25\%. To
         discriminate efficiently between the two competing hypotheses
         of BSS formation in this cluster (binary mergers and
         collisions), we also intend to compare the photospheric He
         abundance of these stars as well as their rotational
         velocities with those of a bright, blue horizontal branch
         (HB) star (V~eq 13), located ~ 10" away from the cluster
         center (outside the field shown in Figure 1). We intend to
         use this star as representative of the properties of the
         cluster population of hot stars, and therefore propose to
         obtain a spectrum with S/N ~eq 100 (with an exposure time of
         ~ 5 min). Should the BSS have anomalously high He abundance,
         this would be evident from a comparison of the HeI Lambda4026
         and Lambda4471 lines in their spectra with the corresponding
         features in the spectrum of the HB star. We expect these
         lines to be easier to detect in the spectra of the two bluer
         BSS objects (Figure 1), for which we intend to obtain longer
         exposures in order to reach S/N of ~ 50 (with an exposure
         time of ~ 10--15 min). Rotational velocities, if larger than
         ~ 250 kms, would result in a noticeable broadening,
         detectable by analyzing the profiles of the HeI and Balmer
         \balpha\ lines. We have used the  calcspec task in the STSDAS
         synphot package to calculate the FOS count rates for our
         selected targets, which predict exposure times ranging from 3
         to 6 minutes to achieve spectra having S/N = 30. These count
         rates and exposure time estimates agree to within 5\% with
         those made using Tables 1--7 and 1--8. Using the FOS
         Worksheet and following the guidelines in the Cycle 6 Phase I
         proposal instructions, we have calculated we require 6
         spacecraft orbits to properly acquire and observe all our
         targets. The steps that we intend to adopt are the following:
         acquire the bright HB star and place it securely inside the
         0.3 aperture; obtain two spectra of it (with the G570H and
         G400H gratings); offset to the first of the six bright BSS
         and acquire it, with a 3 * 3 step peakup sequence within the
         aperture; obtain two spectra (one per grating); move
         consecutively to all the other BSS and repeat these steps for
         all of them. We have already collected FOC F/48 images of a
         field larger than that shown in Figure 1, which includes the
         HB star as well as all the six BSS. These images provide us
         with extremely precise positions for our targets with respect
         to the aquisition stars (better than ~ 0.05" ). This will
         allow us to accurately locate the BSS inside the FOS  0.3
         aperture. We notice here that we can accomodate the short
         exposures needed to obtain a spectrum of the HB star right
         into the target acquisition orbit, so that no additional
         spacecraft time will be required to obtain this ``free''
         observation. The brightness of the HB star and of the six BSS
         makes the acquisition procedure very reliable and accurate,
         and ensures that contamination due to possible nearby objects
         will be negligible. As reported in the Observing Summary on
         page 2 of this proposal, a total of 6 orbits are requested
         for the observations proposed here.

   Real_Time_Justification:
         There are no special calibration requirements; standard
         pipeline wavelength and flux calibrations will suffice for
         our analysis.

Calibration_Justification:              ! Move appropriate text from Real_Time_Justification

      Additional_Comments: The following Phase II proposal utilizes a
non-standard 4-stage peakup acquisition procedure designed by the
proposer. The offset star is too bright to acquire with ACQ/BIN and
the MIRROR element. The sequence will use existing Patterns A and B1,
followed by new Pattern C2 (3X3 at 0.23 arcsec in the (0.5) aperture),
and finally existing Pattern E4 to achieve a critical peakup pointing
accuracy of 0.04 arcsec. I (Rex A. Saffer, Contact CoI) have had
extensive discussions with Instrument Scientists Tony Keyes and
Michael Dahlem about the pointing accuracies resulting from the
procedure, and I am confident that the procedure has an extremely high
probability of success. I am grateful for their expert assistance and
advice.

Fixed_Targets                           ! Section 5.1
  Target_Number: 1
    Target_Name: NGC6397-HB1
    Description: STAR, HORIZONTAL BRANCH STAR
       Position: RA = 17H 40M 41.14S +/- 0.06S,
                 DEC = -53D 40' 25.27" +/- 0.5",
                 PLATE-ID=0688
        Equinox: 2000
           Flux: V = 13.65 +/- 0.1,
                 B-V = +0.16 +/- 0.1
       Comments: Plate ID is for Region XV181. The target is located at x,y
                 coords 6777.7,9938.3 out of 14000x14000 pixels, so there is
                 no overlap possible with other adjacent GS plates, even for
                 the FGSs. It was also checked with Conrad Sturch of GSSS to
                 verify that there were no other special catalogs in place 
                 in the GSC for this target so that the GSs have to have come 
                 from XV181, Plate-ID=0688. ( Reference to pixels above is 
                 referring to the digitized GSSS Plate. Also, the epoch is
                 just the epoch of that plate which is automatically accounted
                 for since the GSs used to make the 1994 FOC observations 
                 were already in the Equinox J2000.0/Epoch 1987.70 reference 
                 frame of XV181 = Plate-ID 0688. )
                 - Ray Lucas - 9 July, 1996

  Target_Number: 2
    Target_Name: NGC6397-BSS1
    Description: STAR, BLUE STRAGGLER
       Position: RA-OFF = +0.765S +/- 0.011S,
                 DEC-OFF = -0.63" +/- 0.10",
                 FROM 1
        Equinox: 2000
           Flux: V = 14.57 +/- 0.1,
                     B-V = +0.29 +/- 0.1

  Target_Number: 3
    Target_Name: NGC6397-BSS2
    Description: STAR, BLUE STRAGGLER
       Position: RA-OFF = +0.810S +/- 0.011S,
                 DEC-OFF = -1.94" +/- 0.10",
                 FROM 1
        Equinox: 2000
           Flux: V = 14.27 +/- 0.1,
                     B-V = +0.33 +/- 0.1

  Target_Number: 4
    Target_Name: NGC6397-BSS3
    Description: STAR, BLUE STRAGGLER
       Position: RA-OFF = +0.950S +/- 0.011S,
                 DEC-OFF = -3.93" +/- 0.10",
                 FROM 1
        Equinox: 2000
           Flux: V = 14.42 +/- 0.1,
                     B-V = +0.16 +/- 0.1

  Target_Number: 5
    Target_Name: NGC6397-BSS4
    Description: STAR, BLUE STRAGGLER
       Position: RA-OFF = +1.185S +/- 0.011S,
                 DEC-OFF = -5.23" +/- 0.10",
                 FROM 1
        Equinox: 2000
           Flux: V = 14.91 +/- 0.1,
                     B-V = +0.22 +/- 0.1

  Target_Number: 6
    Target_Name: NGC6397-BSS5
    Description: STAR, BLUE STRAGGLER
       Position: RA-OFF = +1.095S +/- 0.011S,
                 DEC-OFF = -6.85" +/- 0.10",
                 FROM 1
        Equinox: 2000
           Flux: V = 14.42 +/- 0.1,
                     B-V = +0.23 +/- 0.1

  Target_Number: 7
    Target_Name: NGC6397-BSS6
    Description: STAR, BLUE STRAGGLER
       Position: RA-OFF = +1.315S +/- 0.011S,
                 DEC-OFF = -7.39" +/- 0.10",
                 FROM 1
        Equinox: 2000
           Flux: V = 14.43 +/- 0.1,
                     B-V = +0.24 +/- 0.1

! This is a template for a single visit containing a single exposure
! Repeat exposure and visit blocks as needed

Visits                                  ! Section 6
      Visit_Number: 1
Visit_Requirements:                     ! Section 7.1

! Uncomment or copy visit level special requirements needed
! Most of these requirements (including ORIENT) will limit scheduling

        ! PCS MODE [Fine | Gyro]
        ! GUIDing TOLerance <angle>
        ! DROP TO GYRO IF NECESSARY [NO REACQuisition]
        ! ORIENTation <angle1> TO <angle2>
        ! ORIENTation <angle1> TO <angle2> FROM <visit>
        ! ORIENTation <angle1> TO <angle2> FROM NOMINAL
        ! SAME ORIENTation AS <visit>
        ! CVZ
        ! PARallel
        ! SCHEDulability <percentage>
        ! AFTER <visit> [BY <time1> [TO <time2>]]
        ! AFTER <date>
        ! BEFORE <date>
        ! BETWEEN <date1> AND <date2>
        ! GROUP <visit-list> WITHIN <time>
        ! PERIOD <time> AND ZERO-PHASE <date>
        ! SEQ <visit-list> WITHIN <time>
        ! ON HOLD [FOR <visit-list>]

  On_Hold_Comments:
    Visit_Comments: USE SAME GUIDE STARS AS FOR GO 5644, RELEVANT
                    DATA FOLLOW:
                    Visit Nr: 1                                 
		    SU ID:   01                                 
		    Target:  NGC6397                            
		    Config:  FOC/96                             
		    Start:   Aug 19, 1994 05:10:23 UT (1994.231)
		    End:     Aug 19, 1994 10:59:41 UT (1994.231)
                    GS Star IDs from GO 5644 dataset x2g10101t.shh are:
                    Dominant GS:    0872901553F1  ( Star in FGS1 )
                    Subdominant GS: 0872902125F3  ( Star in FGS3 ) 
                    ( GS info from Ray Lucas - 9 July, 1996 )
 
     Exposure_Number: 1                  ! Section 6.5
        Target_Name: NGC6397-HB1
              Config: FOS/RD
              Opmode: ACQ/PEAK
            Aperture: 4.3
          Sp_Element: G190H
   Time_Per_Exposure: 2.0S
 Optional_Parameters: SCAN-STEP-Y = 1.23,
                      SEARCH-SIZE-X = 1,
                      SEARCH-SIZE-Y = 3
Special_Requirements: ONBOARD ACQ FOR 4
            Comments: Target Acquisition Pattern A
                      Texp revised upward to 2.0s as per Michael Dahlem.

     Exposure_Number: 2                 ! Section 6.5
         Target_Name: NGC6397-HB1
              Config: FOS/RD
              Opmode: ACQ/PEAK
            Aperture: 1.0
          Sp_Element: G190H
   Time_Per_Exposure: 2.0S
 Optional_Parameters: SCAN-STEP-X = 0.61,
                      SCAN-STEP-Y = 0.61,
                      SEARCH-SIZE-X = 6,
                      SEARCH-SIZE-Y = 2
Special_Requirements: ONBOARD ACQ FOR 4
            Comments: Target Acquisition Pattern B1
                      Texp revised upward to 2.0s as per Michael Dahlem.

     Exposure_Number: 3                 ! Section 6.5
         Target_Name: NGC6397-HB1
              Config: FOS/RD
              Opmode: ACQ/PEAK
            Aperture: 0.5
          Sp_Element: G190H
   Time_Per_Exposure: 2.0S
 Optional_Parameters: SCAN-STEP-X = 0.23,
                      SCAN-STEP-Y = 0.23,
                      SEARCH-SIZE-X = 3,
                      SEARCH-SIZE-Y = 3
Special_Requirements: ONBOARD ACQ FOR 4
            Comments: Target Acquisition Pattern C2
                      Texp revised upward to 2.0s as per Michael Dahlem.

     Exposure_Number: 4                 ! Section 6.5
         Target_Name: NGC6397-HB1
              Config: FOS/RD
              Opmode: ACCUM
            Aperture: 1.0
          Sp_Element: G570H
   Time_Per_Exposure: 720S

     Exposure_Number: 5               ! Section 6.5
         Target_Name: NGC6397-HB1
              Config: FOS/RD
              Opmode: ACCUM
            Aperture: 1.0
          Sp_Element: G400H
   Time_Per_Exposure: 600S
Special_Requirements: SAME POS AS 4

     Exposure_Number: 6                 ! Section 6.5
         Target_Name: NGC6397-HB1
              Config: FOS/RD
              Opmode: ACQ/PEAK
            Aperture: 0.3
          Sp_Element: G400H
   Time_Per_Exposure: 1.8S
 Optional_Parameters: SCAN-STEP-X = 0.052,
                      SCAN-STEP-Y = 0.052,
                      SEARCH-SIZE-X = 4,
                      SEARCH-SIZE-Y = 4
Special_Requirements: ONBOARD ACQ FOR 8
            Comments: Target Acquisition Pattern E3, CRITICAL PEAKUP, 
                      EXPOSURE TIME 10X FOR V=13.65

     Exposure_Number: 7                 ! Section 6.5
         Target_Name: NGC6397-BSS2
              Config: FOS/RD
              Opmode: ACQ/PEAK
            Aperture: 0.3
          Sp_Element: G400H
   Time_Per_Exposure: 3.2S
 Optional_Parameters: SCAN-STEP-X = 0.052,
                      SCAN-STEP-Y = 0.052,
                      SEARCH-SIZE-X = 3,
                      SEARCH-SIZE-Y = 3
Special_Requirements: ONBOARD ACQ FOR 8
            Comments: CRITICAL PEAKUP, EXPOSURE TIME 10X FOR V=14.27

     Exposure_Number: 8                ! Section 6.5
         Target_Name: NGC6397-BSS2
              Config: FOS/RD
              Opmode: ACCUM
            Aperture: 0.5
          Sp_Element: G400H
   Time_Per_Exposure: 300S

     Exposure_Number: 9                ! Section 6.5
         Target_Name: NGC6397-BSS2
              Config: FOS/RD
              Opmode: ACCUM
            Aperture: 0.5
          Sp_Element: G570H
   Time_Per_Exposure: 360S
Special_Requirements: SAME POS AS 8

     Exposure_Number: 10                ! Section 6.5
         Target_Name: NGC6397-BSS4
              Config: FOS/RD
              Opmode: ACQ/PEAK
            Aperture: 0.3
          Sp_Element: G570H
   Time_Per_Exposure: 5.8S
 Optional_Parameters: SCAN-STEP-X = 0.052,
                      SCAN-STEP-Y = 0.052,
                      SEARCH-SIZE-X = 3,
                      SEARCH-SIZE-Y = 3
Special_Requirements: ONBOARD ACQ FOR 11
            Comments: CRITICAL PEAKUP, EXPOSURE TIME 10X FOR V=14.91

     Exposure_Number: 11               ! Section 6.5
         Target_Name: NGC6397-BSS4
              Config: FOS/RD
              Opmode: ACCUM
            Aperture: 0.5
          Sp_Element: G570H
   Time_Per_Exposure: 640S

     Exposure_Number: 12                ! Section 6.5
         Target_Name: NGC6397-BSS4
              Config: FOS/RD
              Opmode: ACCUM
            Aperture: 0.5
          Sp_Element: G400H
   Time_Per_Exposure: 530S
Special_Requirements: SAME POS AS 11

     Exposure_Number: 13                 ! Section 6.5
         Target_Name: NGC6397-BSS1
              Config: FOS/RD
              Opmode: ACQ/PEAK
            Aperture: 0.3
          Sp_Element: G400H
   Time_Per_Exposure: 4.2S
 Optional_Parameters: SCAN-STEP-X = 0.052,
                      SCAN-STEP-Y = 0.052,
                      SEARCH-SIZE-X = 3,
                      SEARCH-SIZE-Y = 3
Special_Requirements: ONBOARD ACQ FOR 14
            Comments: CRITICAL PEAKUP, EXPOSURE TIME 10X FOR V=14.57

     Exposure_Number: 14                 ! Section 6.5
         Target_Name: NGC6397-BSS1
              Config: FOS/RD
              Opmode: ACCUM
            Aperture: 0.5
          Sp_Element: G400H
   Time_Per_Exposure: 390S

     Exposure_Number: 15                 ! Section 6.5
         Target_Name: NGC6397-BSS1
              Config: FOS/RD
              Opmode: ACCUM
            Aperture: 0.5
          Sp_Element: G570H
   Time_Per_Exposure: 470S
Special_Requirements: SAME POS AS 14

     Exposure_Number: 16                ! Section 6.5
         Target_Name: NGC6397-BSS3
              Config: FOS/RD
              Opmode: ACQ/PEAK
            Aperture: 0.3
          Sp_Element: G570H
   Time_Per_Exposure: 3.7S
 Optional_Parameters: SCAN-STEP-X = 0.052,
                      SCAN-STEP-Y = 0.052,
                      SEARCH-SIZE-X = 3,
                      SEARCH-SIZE-Y = 3
Special_Requirements: ONBOARD ACQ FOR 17
            Comments: CRITICAL PEAKUP, EXPOSURE TIME 10X FOR V=14.42

     Exposure_Number: 17                ! Section 6.5
         Target_Name: NGC6397-BSS3
              Config: FOS/RD
              Opmode: ACCUM
            Aperture: 0.5
          Sp_Element: G570H
   Time_Per_Exposure: 470S

     Exposure_Number: 18               ! Section 6.5
         Target_Name: NGC6397-BSS3
              Config: FOS/RD
              Opmode: ACCUM
            Aperture: 0.5
          Sp_Element: G400H
   Time_Per_Exposure: 400S
Special_Requirements: SAME POS AS 17

     Exposure_Number: 19                ! Section 6.5
         Target_Name: NGC6397-BSS5
              Config: FOS/RD
              Opmode: ACQ/PEAK
            Aperture: 0.3
          Sp_Element: G400H
   Time_Per_Exposure: 3.7S
 Optional_Parameters: SCAN-STEP-X = 0.052,
                      SCAN-STEP-Y = 0.052,
                      SEARCH-SIZE-X = 3,
                      SEARCH-SIZE-Y = 3
Special_Requirements: ONBOARD ACQ FOR 20
            Comments: CRITICAL PEAKUP, EXPOSURE TIME 10X FOR V=14.42

     Exposure_Number: 20                ! Section 6.5
         Target_Name: NGC6397-BSS5
              Config: FOS/RD
              Opmode: ACCUM
            Aperture: 0.5
          Sp_Element: G400H
   Time_Per_Exposure: 460S

     Exposure_Number: 21                ! Section 6.5
         Target_Name: NGC6397-BSS5
              Config: FOS/RD
              Opmode: ACCUM
            Aperture: 0.5
          Sp_Element: G570H
   Time_Per_Exposure: 470S
Special_Requirements: SAME POS AS 20

     Exposure_Number: 22                ! Section 6.5
         Target_Name: NGC6397-BSS6
              Config: FOS/RD
              Opmode: ACQ/PEAK
            Aperture: 0.3
          Sp_Element: G570H
   Time_Per_Exposure: 3.7S
 Optional_Parameters: SCAN-STEP-X = 0.052,
                      SCAN-STEP-Y = 0.052,
                      SEARCH-SIZE-X = 3,
                      SEARCH-SIZE-Y = 3
Special_Requirements: ONBOARD ACQ FOR 23
            Comments: CRITICAL PEAKUP, EXPOSURE TIME 10X FOR V=14.43

     Exposure_Number: 23                ! Section 6.5
         Target_Name: NGC6397-BSS6
              Config: FOS/RD
              Opmode: ACCUM
            Aperture: 0.5
          Sp_Element: G570H
   Time_Per_Exposure: 470S

     Exposure_Number: 24                ! Section 6.5
         Target_Name: NGC6397-BSS6
              Config: FOS/RD
              Opmode: ACCUM
            Aperture: 0.5
          Sp_Element: G400H
   Time_Per_Exposure: 400S
Special_Requirements: SAME POS AS 23

Data_Distribution                       ! Defaults indicated; change if desired

         Medium:        8MM             ! 8MM or 6250BPI or 1600BPI
Blocking_Factor:        10              ! 10 or 1
                                        ! Only astronomers with very old 9-
                                        ! track tape drives should consider
                                        ! a blocking factor of 1

        Ship_To:        Rex A. Saffer
                        3700 San Martin Drive
			Baltimore            
                        21218                
                                        !
                                        !
       Ship_Via:        UPS             ! UPS (2-day) or OVERNIGHT
                                        ! Overnight shipping done at PI expense

Recipient_Email:        saffer@stsci.edu