The current Call for Proposals is for HST Cycle 34. WST Cycle 5 joint JWST - HST proposal. Followed instructions provided by STScI support office. -540050107 Assigned ID: 6958 ----- Attempting Submission 1 (Mon Mar 30 13:59:42 GMT 2026) ----- I was instructed to select cycle33. this is a joint JWST-HST proposal with GO 9734 ORBITAL VISIBILITY OVERRUN ORBITAL VISIBILITY OVERRUN ORBITAL VISIBILITY OVERRUN 0 ----- Attempting Submission 1 (Mon May 04 19:54:09 GMT 2026) ----- ----- Attempting Submission 2 (Thu May 14 20:42:55 GMT 2026) ----- the warnings are related to 23 sec orbit overrun. If this is a problem I'm happy to reduce the single exp time of 10 sec. Feedback in Low-metallicity Environments from Emerging sTar clusters (FLEET) JWST has opened a unique window into the earliest phases of star formation where dust, ionized gas, and massive stars interact while consuming the gas reservoir. The duration of the emerging phase of star formation is among the most challenging to constrain. Analyses in metal-rich spirals find that the 3.3 micron PAH feature, a tracer of photo-dissociation regions (PDRs), remains associated with emerging young star clusters (eYSCs) for about 4 Myr, too long for large fractions of ionizing radiation to escape. At low metallicity, however, harder radiation fields and altered dust composition may change this picture. FLEET will target nine dwarf galaxies (3-8 Mpc) with vigorous star formation, spanning metallicities of 10-40% Zsun, to sample eYSCs (10^3-10^5 Msun) and their associated H II regions and PDRs at 1-5 pc resolution. From multiband NIRCam and MIRI imaging (complemented by HST observations), we will determine the timescales for clusters to emerge from their natal clouds as a function of their mass. By controlling for proximity and cluster properties (emerging stage, mass, age), we will trace PAH grain composition and its evolution, testing model predictions (inhibited growth vs. destruction) that diverge at the probed metallicity range. We will calibrate the PAH and 21 micron emission as unobscured tracers of star formation. The results of the FLEET program will establish whether cluster emergence is sufficiently short (<<4 Myr) to allow ionizing photon escape, and provide a benchmark for studies of distant dwarf galaxies and simulations of emission and dust content in low-metallicity molecular clouds across a broad range of eYSC properties. The program will acquire 3 orbits with WFC3/UVIS to observe NGC625 in the F336W, F438W, F547M, F657N, F814W filters standard for optical studies. For Visit 1 (NGC625) we use as pattern WFC3-UVIS-GAP-LINE with 3 dithers which cover the gap while sampling the PSF(half px). We cover 1 dither step in each orbit, acquiring 5 exposures (one per filter). For the target ESO245 we use the WFC3-UVIS-MOS-DITH-LINE with 4 positions to cover the gap while appling small dither to better sample the gap. Single exposures include POSTFLASH to reduce CTE effects. joint JWST-HST program, with HST as secondary Galaxies Stellar Populations and the Interstellar Medium 6 false false false false false false false true SECONDARY JWST 9734 false SUPPORTED GALAXY DWARF COMPACT STAR FORMING REGION This object was generated by the targetselector and retrieved from the SIMBAD database. J2000 J2000 GALAXY DWARF COMPACT STAR FORMING REGION This object was generated by the targetselector and retrieved from the SIMBAD database. J2000 J2000 WFC3/UVIS Imaging No No F336W WFC3/UVIS Imaging No No F438W WFC3/UVIS Imaging No No F547M WFC3/UVIS Imaging No No F657N WFC3/UVIS Imaging No No F814W WFC3/UVIS Imaging No No F657N POS-TARG MOSAIC DITHER 4 2.414 WFC3-UVIS-DITHER-BOX false 81.785 true 0.112 0.173 3 85.759 POS-TARG WFC3-UVIS-GAP-LINE 23.884 1 false POS-TARG MOSAIC DITHER 2 2.4 WFC3-UVIS-MOS-DITH-LINE false true 0.119 2 85.754 POS-TARG WFC3-UVIS-MOS-DITH-LINE 33.606 2 true /private/var/folders/b0/zs2vqn9x4qvbbzp70f69k49m0000gn/T/OPVisit13233782835324217871.xml The scheduling data was generated by CASM 34.0. CASM was run in Phase II mode. (Tic-Visit :proposal-id 18240 :visit-id "01" :proposal-version -1 :trans-version "20250929" :date "14-May-2026 22:38:01.0" :trans-errors '(:WARNINGS 2 :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 4331232 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 18240 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 18240 :visit-id "01" :orbit-number 1 :pcs-time 380 :si-vis-utilization 2621 :al-overhead-at-end 123 :internal-dur-at-end 668 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3001 :pcs-gap 0 ) (Tic-Orbit :proposal-id 18240 :visit-id "01" :orbit-number 2 :pcs-time 380 :si-vis-utilization 2644 :al-overhead-at-end 123 :internal-dur-at-end 668 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3001 :pcs-gap 0 ) (Tic-Orbit :proposal-id 18240 :visit-id "01" :orbit-number 3 :pcs-time 380 :si-vis-utilization 2644 :al-overhead-at-end 123 :internal-dur-at-end 668 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3001 :pcs-gap 0 ) true 3 2 /private/var/folders/b0/zs2vqn9x4qvbbzp70f69k49m0000gn/T/OPVisit198115287303233760.xml The scheduling data was generated by CASM 34.0. CASM was run in Phase II mode. (Tic-Visit :proposal-id 18240 :visit-id "02" :proposal-version -1 :trans-version "20250929" :date "14-May-2026 22:37:06.0" :trans-errors '(:WARNINGS 1 :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 1154992 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 18240 :visit-id "02" :obset-id "02" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 18240 :visit-id "02" :orbit-number 1 :pcs-time 380 :si-vis-utilization 2625 :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 3001 :pcs-gap 0 ) true 1 1