Note that the time windows are almost notional. There is a lot of flexibility to adapt to scheduling constraints
but this will be left to a phase II effort if this request is approved.-2035724945Assigned ID: 1104
----- Attempting Submission 1 (Wed Apr 22 00:23:27 GMT 2020) -----Be very careful mixing POS TARG and Center_Pattern = Yes
Be very careful mixing POS TARG and Center_Pattern = Yes
Be very careful mixing POS TARG and Center_Pattern = Yes0----- Attempting Submission 1 (Thu Apr 23 16:45:32 GMT 2020) -----The POSTARG and center flag have been used and tested before on other programs as designed here.HIgh-precision astrometry of (15094) Polymele in support of the Lucy MissionWe propose a targeted set of observations of (15094) Polymele which is the smallest prime target for the Lucy mission. The goal of these observations is to get high-precision astrometry at three epochs. This astrometry will be used to reduce the uncertainties of Polymele's orbit estimate needed to enable a high-chord-density occultation observation later in 2020.All visits are independent and identical except for when they need to execute. We will take 5 full-frame WFC3/UVIS images of the field containing Polymele. The exposure time is set to fully utilize the visibility window and small adjustments are acceptible to adapt to slight changes in the visibility window. The placement of Polymele is initially set for the default location (POSTARG=0). All observations will track Polymele meaning the stars will be trailed by target motion and HST motion-induced parallax.
As work begins to schedule each visit, we need an opportunity to check the candidate windows for suitability. We have a system in place that allows checking for sufficient Gaia DR2 reference stars in the field and to avoid overlap with the target at the star trails given a table of candidate window from STScI. This is the same process that we have been using for all of our Arrokoth, Oumuamua, and Borisov observations with HST. Field star interference is grounds for rejecting a window. The use of POSTARG and small changes to roll angle are used in cases where the field star density is low and an adjustment is needed to increase the number of field stars. We will not use these adjustments unless absolutely necessary. They are not for optimizing the visit but rather to improve one option to get even a single candidate that will work. So far, that has only been necessary for the Oumuamua observations. For reference, getting 6 or so field stars has generally been good enough but having fewer means we will look for better options.
The scheduling windows are meaningful but there is additional flexibility available if the initial windows prove to be too restrictive. Notionally, we want to attempt observations in June, July, and September. The overall requirement is to spread out the three visits between the end of the solar exclusion window and the occultation in September. The initial placement of the first two visits gives us a backup window in August in case one of these fails. The September window is set to be just before the occultation with sufficient width to be schedulable and provide sufficient time after observation to process the data, update the orbit fit, and provide an occultaiton prediction update. The end of the window is the more stringent constraint.Buie - Lead on data analysis and extraction of high-precision astrometry and also lead on occultation deployments. Lucy science team member.
Noll - Experience with HST observations and project scientist for the Lucy mission.
Levison - PI of the Lucy mission and provides project goals and uses project results for the mission development.
Olkin - deputy PI of the Lucy mission, also providing project goals and use of project results for mission development.Solar System Astronomy0falseSUPPORTEDSOLAR SYSTEMUpdates to the orbit during the execution of this program are unlikely. We have already worked with JPL to produce this orbit and any future updates will only be important for occultaiton planning and not at all important for HST.ASTEROIDLucy mission targetTYPE=ASTEROID,A=5.168430829356419,E=0.09482321984419208,I=12.98961897481968
,O=50.31762273700706,W=4.401542022614581,M=295.7073098559924,EQUINOX=J2000,EPOCH=05-AUG-2019:00:00:00,EpochTimeScale=TDBEARTHWFC3/UVISImagingNoNoF350LPWFC3/UVISImagingNoNoF350LPWFC3/UVISImagingNoNoF350LPCELESTIALOTHER0.03LINEfalsetrue50LINE1falseUsing ephemeris for target 16112-01-POLYMELEephemeris data for target 16112-01-POLYMELE does not cover planning interval. Physical constraints are assumed to be unschedulable outside of the ephemeris data. Planning interval: 19.213 to 21.091. ephemeris interval: 20.091 to 22.091The scheduling data was generated by CASM 28.0.CASM was run in Phase II mode.All visits have the same structure with 5 long, dithered exposures that fill the orbit. The only variable is how the visits are scheduled.1591911816000243.74293543154477(Tic-Visit
:proposal-id 16112
:visit-id "01"
:proposal-version -1
:trans-version "20191203"
:date "23-Apr-2020 10:43:53.0"
:trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0
:FATAL-ERRORS 0 :CONTINUABLE-FATALS 0)
:number-of-orbits 1
:saa-model "29"
:si-bright-earth-limb-angle 20.0
:data-volume 1443744
:tdrss-contact-duration 0
:coron NIL
)
(Tic-Obset
:proposal-id 16112
:visit-id "01"
:obset-id "01"
:pcs-mode "FGS"
)
(Tic-Orbit
:proposal-id 16112
:visit-id "01"
:orbit-number 1
:pcs-time 393
:si-vis-utilization 2721
:al-overhead-at-end 0
:internal-dur-at-end 668
:dark-offset NIL
:dark-utilization 0
:max-dark-utilization 1920
:low-sky "N"
:pcs-visibility 3142
:pcs-gap 0
)true10Using ephemeris for target 16112-02-POLYMELEephemeris data for target 16112-02-POLYMELE does not cover planning interval. Physical constraints are assumed to be unschedulable outside of the ephemeris data. Planning interval: 19.213 to 21.091. ephemeris interval: 20.091 to 22.091The scheduling data was generated by CASM 28.0.CASM was run in Phase II mode.All visits have the same structure with 5 long, dithered exposures that fill the orbit. The only variable is how the visits are scheduled.1594062499000242.8910769771436(Tic-Visit
:proposal-id 16112
:visit-id "02"
:proposal-version -1
:trans-version "20191203"
:date "23-Apr-2020 10:43:53.0"
:trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0
:FATAL-ERRORS 0 :CONTINUABLE-FATALS 0)
:number-of-orbits 1
:saa-model "29"
:si-bright-earth-limb-angle 20.0
:data-volume 1443744
:tdrss-contact-duration 0
:coron NIL
)
(Tic-Obset
:proposal-id 16112
:visit-id "02"
:obset-id "02"
:pcs-mode "FGS"
)
(Tic-Orbit
:proposal-id 16112
:visit-id "02"
:orbit-number 1
:pcs-time 393
:si-vis-utilization 2721
:al-overhead-at-end 0
:internal-dur-at-end 668
:dark-offset NIL
:dark-utilization 0
:max-dark-utilization 1920
:low-sky "N"
:pcs-visibility 3142
:pcs-gap 0
)false10Using ephemeris for target 16112-03-POLYMELEephemeris data for target 16112-03-POLYMELE does not cover planning interval. Physical constraints are assumed to be unschedulable outside of the ephemeris data. Planning interval: 19.213 to 21.091. ephemeris interval: 20.091 to 22.091The scheduling data was generated by CASM 28.0.CASM was run in Phase II mode.All visits have the same structure with 5 long, dithered exposures that fill the orbit. The only variable is how the visits are scheduled.(Tic-Visit
:proposal-id 16112
:visit-id "03"
:proposal-version -1
:trans-version "20200619"
:date "22-Jul-2020 10:15:58.0"
:trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0
:FATAL-ERRORS 0 :CONTINUABLE-FATALS 0)
:number-of-orbits 1
:saa-model "29"
:si-bright-earth-limb-angle 20.0
:data-volume 1443744
:tdrss-contact-duration 0
:coron NIL
)
(Tic-Obset
:proposal-id 16112
:visit-id "03"
:obset-id "03"
:pcs-mode "FGS"
)
(Tic-Orbit
:proposal-id 16112
:visit-id "03"
:orbit-number 1
:pcs-time 393
:si-vis-utilization 2721
:al-overhead-at-end 0
:internal-dur-at-end 668
:dark-offset NIL
:dark-utilization 0
:max-dark-utilization 1920
:low-sky "N"
:pcs-visibility 3142
:pcs-gap 0
)false10