Target 288P: There is no need or capability to test the scheduling of observations of moving targets in Phase I. This warning will go away the next time the proposal is loaded. 0 Assigned ID: 523 ----- Attempting Submission 1 (Fri Apr 07 13:59:33 GMT 2017) ----- HST Phase I Proposal 523 (apt_proposal_agarwal_hst25_288P_binary.pdf.apt) successfully submitted. Receipt: # 523-1 The scheduling of a moving target cannot be tested in Phase I, but we have checked that the target at the proposed epochs of observation is at a solar elongation >50 degrees and that its apparent motion is compatible with the tracking capability of the HST.. The unique ID for this investigator was not found in the STScI database. The unique ID for this investigator was not found in the STScI database. The unique ID for this investigator was not found in the STScI database. The unique ID for this investigator was not found in the STScI database. The unique ID for this investigator was not found in the STScI database. FLASH level may be too low for this exposure or a short subexposure. See extended explanation in the diagnostic browser FLASH level may be too low for this exposure or a short subexposure. See extended explanation in the diagnostic browser FLASH level may be too low for this exposure or a short subexposure. See extended explanation in the diagnostic browser FLASH level may be too low for this exposure or a short subexposure. See extended explanation in the diagnostic browser FLASH level may be too low for this exposure or a short subexposure. See extended explanation in the diagnostic browser FLASH level may be too low for this exposure or a short subexposure. See extended explanation in the diagnostic browser This submission contains an additional visit 6 to replace the failed visit 3 (approved HOPR 89696 from 10 January 2018). 1513513110 ----- Attempting Submission 1 (Mon Jul 03 20:27:08 GMT 2017) ----- ----- Attempting Submission 2 (Tue Jan 16 13:39:57 GMT 2018) ----- The flash warning is not triggered if running the ETC with the zodiacal light calculated for the actual sky positions of the target at the targeted epochs of visit 6. The background on May-15 is 15 e-/px (ETC run WFC3UVIS.im.1045051). The 288P (300163) binary asteroid system is unique and puzzling for its unusual combination of properties. It combines a wide separation with near-equal component sizes, and a high eccentricity with alignment of the mutual and heliocentric orbital planes. In addition, it is one of five known active asteroids with sublimation-driven dust production. Orbital fits to high-resolution data obtained in Cycle 24 are inconclusive regarding the orbital period and therefore the total angular momentum content, crucial to discriminate between formation of the binary system via rotational fission or impact. We request five orbits of HST/WFC3 time to measure the time evolution of the component separation under the favourable viewing geometry along the system's minor axis around the perigee passage in December 2017, to constrain with high certainty the orbital period and eccentricity of the system, and therefore its total angular momentum content. This is crucial to discriminate between the two formation scenarios and to understand the connection between the activity and the binary nature. As 288P is heading towards aphelion, the next opportunity to resolve its components will be in 2021. We propose to observe 288P at five epochs between 2017 August and 2018 February. The timing of each visit is flexible within +/-1 week. The first two visits will distiguish between different groups of orbit solutions compatible with Cycle 24 data. Visits 3-5 will serve to constrain the eccentricity of a Group 1 orbit, and to search for changes in the orbital elements induced by the activity. All five orbits will be suited for the search for additional satellites. We expect each component to have V~22. The orbital visibility for a solar system target near the ecliptic plane is 54 min (Section 6.3 of the HST Primer document). In each orbit, we will take 8 exposures of ~225s using the 1k subarray of WFC3 and perform a subsampling dither box pattern, obtaining 2 exposures at each dither point. We will carefully drizzle our subsampled images to a finer output pixel scale to extract the extra spatial information gathered by our subsampling strategy. This enhanced resolution will give us the highest accuracy in measuring the projected component distance and thus constrain their mutual orbit. The dithering will also enable us to reject hot pixels and cosmic ray hits. This strategy gives us a total exposure time of 1800s = 30min, and estimated overheads of 6min for guide-star acquisition, 2.6min for the first exposure, a total of 14.7min for the subsequent 7 exposures, and 1.5min for the three spacecraft maneuvers required for dithering, which adds up to a total execution time of 54min per orbit. This dither strategy is identical to the one employed successfully during Cycle 24, ensuring maximum comparability of the data. We will use the wide bandpass filter F606W for an optimum trade-off between sensitivity and highest resolution: the bandpass (475 -- 700 nm) covers the maximum of the solar spectrum, and is in the wavelength range where the PSF is smallest (FWHM<0.07 arcsec, from the WFC3 Instrument Handbook for Cycle 25), such that we can optimally exploit our subsampling dither strategy. In addition, F606W is the same filter we used to observe 288P in GO 12597, 14790, 14864, and 14884, enabling a direct comparison of the data sets. The WFC3 exposure time calculator returns for a solar-spectrum point source at V=22, exposure time of 225s, F606W filter, and default background values a signal-to-noise-ratio of 79 within a circle of 0.08 arcsec (ETC Request ID: WFC3UVIS.im.939003). The small aperture is needed to separate the fluxes from the two components as far as possible given the expected overlapping of the PSFs. A point source at V=27.4 will be detectable at SNR=5 in the standard 0.2arcsec aperture after stacking all eight exposures, allowing us to search for additional satellites down to a diameter of 130m that may have been hidden in the dust during all previous HST observations of the system (for an assumed geometric albedo of 0.04, heliocentric and geocentric distances of 3 and 2 AU, respectively, and during opposition). To discriminate between different orbital period regimes (Group 2 vs. Group 1+3), it is critical that the system be observed at very specific times, when the predicted component separation differs maximally between the two regimes. Therefore, Visits 1 and 2 should be scheduled within +/-1 week of 2017 August 28 and November 16. Visits 3 - 5 should follow in ~1 month steps between late December and late February to take full advantage of the perigee passage on December 31, ensuring maximum angular separation and maximum sensitivity of the component separation to the eccentricity at apoapsis. The optimum timing of Visit 1 implies that we request early implementation a month prior to the beginning of Cycle 25 (change request 88265 submitted on June 29, 2017). We could not request this observation in a Cycle 24 mid-cycle proposal, because the last data on which the current orbit fit is based were aquired only one day prior to the second mid-cycle deadline. Solar System 6 false false false false false false SUPPORTED SOLAR SYSTEM NO COMET Comet 288P (300163, VW139) TYPE=COMET,Q=2.433757796112896,E=0.201280124072449,I=3.240701450960771,O=83.19018988764668,W=281.3064762224968,T=16-JUL-2011:11:50:43,TTimeScale=TDB,EQUINOX=J2000,EPOCH=18-AUG-2013:00:00:00,EpochTimeScale=TDB EARTH WFC3/UVIS Imaging No No F606W WFC3/UVIS Imaging No No F606W WFC3/UVIS Imaging No No F606W WFC3/UVIS Imaging No No F606W WFC3/UVIS Imaging No No F606W POS-TARG DITHER 0.173 LINE 0.112 false false 81.785 4 23.884 WFC3-UVIS-DITHER-BOX 1 false 1499070294777 The scheduling data was generated by CASM 25.2. CASM was run in Phase II mode. 1503586365000 268.5 (Tic-Visit :proposal-id 15328 :visit-id "01" :proposal-version -1 :trans-version "20170613" :date "03-Jul-2017 10:24:54.0" :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 142608 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 15328 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 15328 :visit-id "01" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2674 :al-overhead-at-end 0 :internal-dur-at-end 192 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3202 :pcs-gap 0 ) true 1 0 The flash warning is not triggered if running the ETC with the zodiacal light calculated for the actual sky positions of the target at the targeted epochs of visits 1-5. The background is on Aug-20 45 e-/px, and between 17 and 20 e-/px for visits 2-5. (ETC runs WFC3UVIS.im.1004647, 1004651, 1004654,1004655, 1004656). 1499070363366 The scheduling data was generated by CASM 25.2. CASM was run in Phase II mode. 1510281196000 279.2527645037952 (Tic-Visit :proposal-id 15328 :visit-id "02" :proposal-version -1 :trans-version "20170613" :date "03-Jul-2017 10:26:02.0" :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 142608 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 15328 :visit-id "02" :obset-id "02" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 15328 :visit-id "02" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2674 :al-overhead-at-end 0 :internal-dur-at-end 192 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3202 :pcs-gap 0 ) true 1 0 The flash warning is not triggered if running the ETC with the zodiacal light calculated for the actual sky positions of the target at the targeted epochs of visits 1-5. The background is on Aug-20 45 e-/px, and between 17 and 20 e-/px for visits 2-5. (ETC runs WFC3UVIS.im.1004647, 1004651, 1004654,1004655, 1004656). 1499070597403 The scheduling data was generated by CASM 25.2. CASM was run in Phase II mode. 1514388236000 264.2500923895555 (Tic-Visit :proposal-id 15328 :visit-id "03" :proposal-version -1 :trans-version "20170613" :date "03-Jul-2017 10:29:56.0" :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 142608 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 15328 :visit-id "03" :obset-id "03" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 15328 :visit-id "03" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2674 :al-overhead-at-end 0 :internal-dur-at-end 192 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3202 :pcs-gap 0 ) true 1 0 The flash warning is not triggered if running the ETC with the zodiacal light calculated for the actual sky positions of the target at the targeted epochs of visits 1-5. The background is on Aug-20 45 e-/px, and between 17 and 20 e-/px for visits 2-5. (ETC runs WFC3UVIS.im.1004647, 1004651, 1004654,1004655, 1004656). 1499070604674 The scheduling data was generated by CASM 25.2. CASM was run in Phase II mode. (Tic-Visit :proposal-id 15328 :visit-id "04" :proposal-version -1 :trans-version "20170613" :date "03-Jul-2017 10:30:04.0" :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 142608 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 15328 :visit-id "04" :obset-id "04" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 15328 :visit-id "04" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2674 :al-overhead-at-end 0 :internal-dur-at-end 192 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3202 :pcs-gap 0 ) true 1 0 The flash warning is not triggered if running the ETC with the zodiacal light calculated for the actual sky positions of the target at the targeted epochs of visits 1-5. The background is on Aug-20 45 e-/px, and between 17 and 20 e-/px for visits 2-5. (ETC runs WFC3UVIS.im.1004647, 1004651, 1004654,1004655, 1004656). 1499070608692 The scheduling data was generated by CASM 25.2. CASM was run in Phase II mode. (Tic-Visit :proposal-id 15328 :visit-id "05" :proposal-version -1 :trans-version "20170613" :date "03-Jul-2017 10:30:08.0" :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 142608 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 15328 :visit-id "05" :obset-id "05" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 15328 :visit-id "05" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2674 :al-overhead-at-end 0 :internal-dur-at-end 192 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3202 :pcs-gap 0 ) true 1 0 The flash warning is not triggered if running the ETC with the zodiacal light calculated for the actual sky positions of the target at the targeted epochs of visits 1-5. The background is on Aug-20 45 e-/px, and between 17 and 20 e-/px for visits 2-5. (ETC runs WFC3UVIS.im.1004647, 1004651, 1004654,1004655, 1004656). 1516109553420 Using ephemeris for target 15328-06-288P ephemeris data for target 15328-06-288P does not cover planning interval. Physical constraints are assumed to be unschedulable outside of the ephemeris data. Planning interval: 17.205 to 19.091. ephemeris interval: 17.365 to 20.001 The scheduling data was generated by CASM 25.2. CASM was run in Phase II mode. /tmp/OPVisit744441679202648361.xml (Tic-Visit :proposal-id 15328 :visit-id "06" :proposal-version -1 :trans-version "20171009" :date "16-Jan-2018 14:32:32.0" :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 142608 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 15328 :visit-id "06" :obset-id "06" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 15328 :visit-id "06" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2674 :al-overhead-at-end 0 :internal-dur-at-end 192 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3202 :pcs-gap 0 ) true 1 0 The flash warning is not triggered if running the ETC with the zodiacal light calculated for the actual sky positions of the target at the targeted epoch of visit 6. The background on May-15 is 15 e-/px (ETC runs WFC3UVIS.im.1045051).