0 Assigned ID: 5929 ----- Attempting Submission 1 (Fri Sep 13 18:53:31 GMT 2024) ----- This is the initial submission for this program. We employ a standard 3-point gap dither, but we use POS TARGs to get just 2-point dithers for the short broadband exposures which will have fewer cosmic rays. We specify an orient range which is schedulable from Nov to Dec and should not restrict scheduling much. -- Max Mutchler Edit 10/03/24 V Bajaj: Added tiny subpixel offsets to the postargs to sample pixel phases more evenly. -2140600221 ----- Attempting Submission 1 (Tue Sep 24 18:15:47 GMT 2024) ----- Your proposal could not be saved. Submission aborted. ----- Attempting Submission 2 (Thu Oct 03 21:53:42 GMT 2024) ----- We propose to take deep narrowband imaging of the planetary nebula NGC 2899. Deep H-alpha, [NII], and [OIII] images in F656N, F658N, and F502N will sample different density and temperature regions within the nebula. We will obtain high signal-to-noise imaging of NGC 2899 in narrowband filters F502N, F656N, and F658N as well as broadband filters F436W, F555W and F814W to highlight the atomic emission lines in the nebula and enable color-balancing the stars, respectively. We propose a single WFC3 pointing which will adequately cover the entire object. We expect to be able to complete observations in a single visit, such that matching position angles in the event of any guide star failures is not a concern. NGC 2899 nearly fills the WFC3 field-of-view and can be observed at any available position angle. We will also employ a dither pattern which fills the chip gaps and enables cosmic ray rejection. The dither pattern will ensure that even the outlying parts of the nebula on the long axis are covered. The nebula has a bright limb in an hourglass shape with a fainter cavity in the middle. We calculate exposure times via the WFC ETC and find that we will acquire high signal-to-noise images suitable for public outreach with a minimum of 800 s in F656N, 300 s in F658N, and 400s of [O III] spread across 3 dithers. However, in order to accommodate buffer dumps, the individual exposures for each dither position must be above 370s, except for bookend exposures. We will place the broadband filters on the bookends since they can be much shallower, and cycling through each narrowband dither position will occupy 1 orbit for each dither, such that we require 3 orbits of HST time for this target. Most of the color in the composite image will derive from the contrasting ionization thresholds and density sensitivities for [O III]. [N II], and H-alpha in the F502, F656N, and F658N filters. The broadband filters are included to get a natural color balance on stars in the image. The team has a wealth of experience in making outreach images for the Hubble Space Telescope and is responsible for creating Hubble images viewed by billions of people world-wide, includingthe 31st, 32nd, 33rd, and 34th anniversary images which together were viewed over 3 billion times. The team includes decades of experience in writing Hubble news releases, designing informal educational and outreach products based on Hubble data, as well as instrument expertise specializing in treatment of WFC3 data. Stellar Physics and Stellar Types 0 false SUPPORTED EXT-STAR PLANETARY NEBULA CENTRAL STAR YES This object was generated by the targetselector and retrieved from the SIMBAD database. J2000 J2000 WFC3/UVIS Imaging No No F502N WFC3/UVIS Imaging No No F656N WFC3/UVIS Imaging No No F658N WFC3/UVIS Imaging No No F438W WFC3/UVIS Imaging No No F814W WFC3/UVIS Imaging No No F555W 1727992403351 The scheduling data was generated by CASM 32.1.3. CASM was run in Phase II mode. (Tic-Visit :proposal-id 17855 :visit-id "01" :proposal-version -1 :trans-version "20240604" :date "03-Oct-2024 17:53:22.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 3 :saa-model "29" :si-bright-earth-limb-angle 20.0 :data-volume 4331184 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 17855 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 17855 :visit-id "01" :orbit-number 1 :pcs-time 380 :si-vis-utilization 2699 :al-overhead-at-end 105 :internal-dur-at-end 668 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3099 :pcs-gap 0 ) (Tic-Orbit :proposal-id 17855 :visit-id "01" :orbit-number 2 :pcs-time 380 :si-vis-utilization 2697 :al-overhead-at-end 104 :internal-dur-at-end 668 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3099 :pcs-gap 0 ) (Tic-Orbit :proposal-id 17855 :visit-id "01" :orbit-number 3 :pcs-time 380 :si-vis-utilization 2670 :al-overhead-at-end 127 :internal-dur-at-end 668 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3099 :pcs-gap 0 ) false 3 0