0 Assigned ID: 6489 ----- Attempting Submission 1 (Thu Apr 10 15:46:29 GMT 2025) ----- A target acquisition should probably be performed before doing spectroscopy or coronography with STIS or COS. A target acquisition should probably be performed before doing spectroscopy or coronography with STIS or COS. Phase 2 re-submission for HST Program 18109 (PI Jacobson-Galan). Updated "TIME-TAG" and buffer times. -253031075 ----- Attempting Submission 1 (Wed Aug 13 17:17:19 GMT 2025) ----- ----- Attempting Submission 2 (Tue Dec 02 04:48:56 GMT 2025) ----- ----- Attempting Submission 3 (Fri Jan 30 06:40:15 GMT 2026) ----- HST Phase II Proposal 18109 successfully submitted. Receipt: # 18109-3 ----- Attempting Submission 4 (Fri Jan 30 16:10:16 GMT 2026) ----- Warnings Lightning Strikes Twice: A Panchromatic View of Shock Power in the Closest Type II Supernovae of the Decade Late-time observations of type II supernovae (SNe II) are a window into the uncertain mass-loss history of their red supergiant (RSG) star progenitors as well as a direct probe of the physics of shock interaction as SN ejecta collide with distant circumstellar material (CSM). We propose a long term monitoring program to obtain HST UV spectroscopy of SNe II 2023ixf and 2024ggi, the closest SNe of the decade, that currently show excess X-ray-to-radio emission at late-times from on-going CSM interaction. This unprecedented multi-wavelength campaign will enable the first spectral energy distributions of their kind, capable of directly constraining the unknown thermalization efficiency of radiation produced by the SN shock and the characterization of UV emission line spectra from the post-shock gas. These observations will also directly constrain the highly debated mass-loss histories of RSGs in the final centuries-to-millenia before core-collapse. This program is to observe SN 2023ixf and SN 2024ggi in the FUV and NUV. Each object will be observed once during Cycle 33 with 4 orbits (2 FUV, 2 NUV) per object. The faintest SN 2023ixf will be during the cycle is V=20mag and the faintest SN 2024ggi will be is V=21 mag. Dr. Wynn Jacobson-Galan is a NASA Hubble Fellow with extensive experience analyzing and reducing data from CSM-interacting supernovae (4 published papers). Prof. Raffaella Margutti is a leading expert on X-ray and radio observations of interacting supernovae. Dr. Luc Dessart is one of the world's leading experts on radiative transfer codes (CMFGEN) and hydrodynamics simulations (HERACLES). Drs. Armin Rest, Charles Kilpatrick, Matthew Siebert and Melissa Shahbandeh have significant experience in reduction and analysis of JWST NIRCam/MIRI imaging/spectroscopy data, including the prime instruments used in these proposed observations. Dr. Ori Fox is one of the world's leading experts on dust formation in type II supernovae. Profs. Ryan Foley, Ryan Chornock, and Alex Filippenko are an expert in transient surveys and follow up of all types of explosive transients. Dr. Qinan Wang and Mr. Kyle Davis will assist with data reduction and analysis of all targets obtained through these programs. Dr. Nayana AJ is leading the radio follow-up campaign for SN 2023ixf. Stellar Physics and Stellar Types 0 false true false false false false false SUPPORTED EXT-STAR SUPERNOVA TYPE II This object was generated by the targetselector and retrieved from the SIMBAD database. J2000 J2000 EXT-STAR SUPERNOVA TYPE II This object was generated by the targetselector and retrieved from the SIMBAD database. J2000 J2000 EXT-STAR K V-IV g=20.48, r=20.43, z=20.39 J2000 STIS/FUV-MAMA Spectroscopic No No G140L 1425 STIS/NUV-MAMA Spectroscopic No No G230L 2376 STIS/FUV-MAMA Spectroscopic No No G140L 1425 STIS/NUV-MAMA Spectroscopic No No G230L 2376 /System/Volumes/Data/solaris/user1/royle/OP-cache/18109-v01.xml The scheduling data was generated by CASM 34.0. CASM was run in Phase II mode. 1778917550000 177.5771921830393 (Tic-Visit :proposal-id 18109 :visit-id "01" :proposal-version -1 :trans-version "20260319" :date "22-Jun-2026 17:58:19.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 2 :saa-model "24" :si-bright-earth-limb-angle 20.0 :data-volume 313920 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 18109 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 18109 :visit-id "01" :orbit-number 1 :pcs-time 380 :si-vis-utilization 2646 :al-overhead-at-end 0 :internal-dur-at-end 178 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3026 :pcs-gap 0 ) (Tic-Orbit :proposal-id 18109 :visit-id "01" :orbit-number 2 :pcs-time 380 :si-vis-utilization 2646 :al-overhead-at-end 0 :internal-dur-at-end 440 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3026 :pcs-gap 0 ) true 2 0 /System/Volumes/Data/solaris/user1/royle/OP-cache/18109-v02.xml The scheduling data was generated by CASM 34.0. CASM was run in Phase II mode. 1778933966000 177.5771921830393 (Tic-Visit :proposal-id 18109 :visit-id "02" :proposal-version -1 :trans-version "20260319" :date "22-Jun-2026 17:58:20.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 2 :saa-model "24" :si-bright-earth-limb-angle 20.0 :data-volume 313920 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 18109 :visit-id "02" :obset-id "02" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 18109 :visit-id "02" :orbit-number 1 :pcs-time 380 :si-vis-utilization 2646 :al-overhead-at-end 0 :internal-dur-at-end 178 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3026 :pcs-gap 0 ) (Tic-Orbit :proposal-id 18109 :visit-id "02" :orbit-number 2 :pcs-time 380 :si-vis-utilization 2646 :al-overhead-at-end 0 :internal-dur-at-end 440 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3026 :pcs-gap 0 ) true 2 0 The scheduling data was generated by CASM 34.1. CASM was run in Phase II mode. /System/Volumes/Data/solaris/user1/royle/OP-cache/18109-v52.xml (Tic-Visit :proposal-id 18109 :visit-id "52" :proposal-version -1 :trans-version "20260319" :date "22-Jun-2026 17:57:35.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "24" :si-bright-earth-limb-angle 20.0 :data-volume 156960 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 18109 :visit-id "52" :obset-id "52" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 18109 :visit-id "52" :orbit-number 1 :pcs-time 380 :si-vis-utilization 2646 :al-overhead-at-end 0 :internal-dur-at-end 440 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3026 :pcs-gap 0 ) true 1 0 /System/Volumes/Data/solaris/user1/royle/OP-cache/18109-v03.xml The scheduling data was generated by CASM 34.0. CASM was run in Phase II mode. (Tic-Visit :proposal-id 18109 :visit-id "03" :proposal-version -1 :trans-version "20260319" :date "22-Jun-2026 17:58:20.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 2 :saa-model "24" :si-bright-earth-limb-angle 20.0 :data-volume 386688 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 18109 :visit-id "03" :obset-id "03" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 18109 :visit-id "03" :orbit-number 1 :pcs-time 380 :si-vis-utilization 2607 :al-overhead-at-end 0 :internal-dur-at-end 178 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 2987 :pcs-gap 0 ) (Tic-Orbit :proposal-id 18109 :visit-id "03" :orbit-number 2 :pcs-time 380 :si-vis-utilization 2607 :al-overhead-at-end 0 :internal-dur-at-end 440 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 2987 :pcs-gap 0 ) true 2 0 /System/Volumes/Data/solaris/user1/royle/OP-cache/18109-v04.xml The scheduling data was generated by CASM 34.0. CASM was run in Phase II mode. (Tic-Visit :proposal-id 18109 :visit-id "04" :proposal-version -1 :trans-version "20260319" :date "22-Jun-2026 17:58:20.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 2 :saa-model "24" :si-bright-earth-limb-angle 20.0 :data-volume 386688 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 18109 :visit-id "04" :obset-id "04" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 18109 :visit-id "04" :orbit-number 1 :pcs-time 380 :si-vis-utilization 2607 :al-overhead-at-end 0 :internal-dur-at-end 178 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 2987 :pcs-gap 0 ) (Tic-Orbit :proposal-id 18109 :visit-id "04" :orbit-number 2 :pcs-time 380 :si-vis-utilization 2607 :al-overhead-at-end 0 :internal-dur-at-end 440 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 2987 :pcs-gap 0 ) true 2 0