16996( 6) - 06-Dec-2023 20:48:35 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 16996 Version: 6 Check-in Time: 06-Dec-2023 20:48:35 STScI Edit Number: 4 Title The ever-changing face of SN 1987A ------------------------------------------------------------------------------------ Type Cycle GO 30 ------------------------------------------------------------------------------------ Investigators Contact? PI: Dr. Josefin Larsson Royal Institute of Technology Y CoI: Prof. Claes Fransson Stockholm University N CoI: Prof. Robert P. Kirshner Harvard University N CoI: Mr. Peter Challis Harvard University N CoI: Dr. Roger A. Chevalier The University of Virginia N CoI: Prof. Kevin France University of Colorado at Boulder N CoI: Prof. Kevin Heng Ludwig Maximilian Universitat of Munich N CoI: Dr. Dennis Alp Royal Institute of Technology N CoI: Dr. Stephen S. Lawrence Hofstra University N CoI: Prof. Peter Lundqvist Stockholm University N CoI: Dr. George Sonneborn NASA Goddard Space Flight Center N CoI: Dr. Seppo Mattila University of Turku N CoI: Dr. Bruno Leibundgut European Southern Observatory - Germany N CoI: Dr. Patrice Bouchet CEA/DSM/Irfu/Service d'Astrophysique - N Laboratoire AIM CoI: Dr. Nicholas B. Suntzeff Texas A & M University N CoI: Dr. Jesper Sollerman Stockholm University N CoI: Dr. Mikako Matsuura Cardiff University N ------------------------------------------------------------------------------------ Abstract SN 1987A is the great supernova (SN) of the HST era. An unbroken string of observations is the essential tool for detecting change and establishing a uniform legacy archive. Recent imaging has shown dramatic changes in the ejecta and the interaction with the circumstellar material. After a steady increase in flux, the inner circumstellar ring reached a maximum in 2009 and is now fading rapidly as it is destroyed by shocks. At the same time, diffuse emission and new spots outside the inner ring are becoming visible, gradually revealing previously unseen material that extends toward the outer rings. Monitoring this emission is required to understand the formation of the rings and the mass-loss history of the progenitor star. In addition, the expanding innermost ejecta reveal asymmetries and mixing in the explosion. As the ejecta expand, X-rays from the inner ring penetrate into the metal-rich core, which results in a brightening in the optical band. We request imaging in narrow and broad filters over the next three cycles to follow these developments. Annual observations are needed to monitor the rapid evolution of the shocks. Imaging in additional filters in one of the cycles will provide flux measurements crucial to estimating the energy budget of the ejecta, that, perhaps, will begin to reveal the elusive compact object. The HST observations have a unique blend of photometric fidelity and angular resolution that make them the indispensable partner to ongoing X-ray, sub-mm ALMA, and ground-based optical/NIR observations. They are also an important complement to the JWST GTO observations in 2022. ------------------------------------------------------------------------------------ 16996( 6) - 06-Dec-2023 20:48:35 - [ 2] Observations Description ------------------------ We request imaging with WFC3/UVIS in Cycles 28, 29, and 30. The total time requested is 4 + 9 + 4 = 17 orbits. Monitoring: We request imaging with F438W, F625W, F502N, and F657N in all three cycles. With these observations, we will follow the light curve and morphology of the ejecta, the ER, and the new spots and diffuse gas outside the ER. To obtain a similar quality as the previous observations, we need half an orbit each for the broad filters, one orbit for F657N and two orbits for F502N. This amounts to 4 X 3 = 12 orbits over three years. Since 2003, all ACS and WFC3 imaging has used a fixed dither strategy to improve the resolution of the HST PSF. Using the same dither strategy and the empirical PSFs by Anderson (2016), we will use PSF-matched difference imaging (Sugerman 2005) across the full ACS/WFC3 dataset and search for faint changes in the rings and outer structures. Additional filters in Cycle 29: We request imaging with F275W, F336W, F555W, F814W and F280N in Cycle 29 only, which is expected to be close in time to the planned JWST GTO observations. In the event of a significant delay in the JWST launch, we would request the STScI Director to move these observations to Cycle 30. The HST observations in this cycle will give complete coverage of the wavelength interval between 2300A-10000A. The primary science objectives for the broad filters are the energy budget for the ejecta and compact object, but the observations will also measure the other emission components in the system, which can verify our models for the shock interaction. The last time that SN 1987A was observed in all these filters was in 2009. We request a full orbit each in F275W and F336W, which is a significant improvement compared to the 400 s UV-band exposures in the 2009 epoch. The longer exposures are motivated by the relatively low transmission as well as the fact that these filters are important for estimating limits on the compact object. We will need one orbit to cover F555W and F814W. The narrow F280N filter covering the Mg II lambda-2800 lines has not previously been used for SN 1987A, though it is known from STIS spectra that the ejecta are strong in Mg II (Larsson et al. 2013). As described above, these lines can also help refine the shock models for the new spots. The F280N filter will cover almost all ejecta emission inside 2500 km/s, while the highest velocities will be included in the F275W image. Given the filter throughput and the expected strength of the lines, we require two orbits for F280N. ------------------------------------------------------------------------------------ 16996( 6) - 06-Dec-2023 20:48:35 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 SN-1987A EXT-STAR, SUPERNOVA RA=05H35M28.0200S, J2000 V = 22 DEC=-69D16'11.07" Reference Frame: Other: SIMBAD Comments: This object was generated by the targetselector and retrieved from the SIMBAD database. Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 2015.5 0.0 0.0 0.0 ------------------------------------------------------------------------------------------------------------------------------------ 16996( 6) - 06-Dec-2023 20:48:35 - [ 4] Patterns ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 1 Primary_Pattern Secondary_Pattern Pattern_Type WFC3-UVIS-DITHER-BOX Pattern_Purpose DITHER Number_Of_Points 4 Point_Spacing 0.173 Line_Spacing 0.112 Coordinate_Frame POS-TARG Pattern_Orient 23.884 Angle_Between_Sides 81.785 Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ 16996( 6) - 06-Dec-2023 20:48:35 - [ 5] Visit: 01 Visit Requirements: ORIENT 78D TO 82 D; ORIENT 168D TO 172 D; ORIENT 258D TO 262 D; ORIENT 348D TO 352 D; BETWEEN 01-MAY-2023:00:00:00 AND 30-SEP-2023; SEQ 01, 02, 03 WITHIN 7 D On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 SN-1987A WFC3/UVI ACCUM UVIS2-C1K F438W FLASH=14 1 300 S PATTERN 1 1-2 S 1C-SUB (1200 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 SN-1987A WFC3/UVI ACCUM UVIS2-C1K F625W FLASH=9 1 270 S S 1C-SUB (1080 S) ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ SN-1987A 1 WFC3/UVI ACCUM UVIS2-C1 F438W 1 none none none 1 N/A S K1C-SUB SN-1987A 1 WFC3/UVI ACCUM UVIS2-C1 F438W 2 none none none 1 N/A S K1C-SUB SN-1987A 1 WFC3/UVI ACCUM UVIS2-C1 F438W 3 none none none 1 N/A S K1C-SUB SN-1987A 1 WFC3/UVI ACCUM UVIS2-C1 F438W 4 none none none 1 N/A S K1C-SUB SN-1987A 2 WFC3/UVI ACCUM UVIS2-C1 F625W 1 none none none 1 N/A S K1C-SUB SN-1987A 2 WFC3/UVI ACCUM UVIS2-C1 F625W 2 none none none 1 N/A S K1C-SUB SN-1987A 2 WFC3/UVI ACCUM UVIS2-C1 F625W 3 none none none 1 N/A S K1C-SUB SN-1987A 2 WFC3/UVI ACCUM UVIS2-C1 F625W 4 none none none 1 N/A S K1C-SUB 16996( 6) - 06-Dec-2023 20:48:35 - [ 6] Visit: 02 Visit Requirements: ORIENT 78D TO 82 D; ORIENT 168D TO 172 D; ORIENT 258D TO 262 D; ORIENT 348D TO 352 D; SEQ 01, 02, 03 WITHIN 7 D On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 SN-1987A WFC3/UVI ACCUM UVIS2-C1K F657N CR-SPLIT=NO, FLASH=15 1 700 S PATTERN 1 1 S 1C-SUB (2800 S) ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ SN-1987A 1 WFC3/UVI ACCUM UVIS2-C1 F657N 1 none none none 1 N/A S K1C-SUB SN-1987A 1 WFC3/UVI ACCUM UVIS2-C1 F657N 2 none none none 1 N/A S K1C-SUB SN-1987A 1 WFC3/UVI ACCUM UVIS2-C1 F657N 3 none none none 1 N/A S K1C-SUB SN-1987A 1 WFC3/UVI ACCUM UVIS2-C1 F657N 4 none none none 1 N/A S K1C-SUB 16996( 6) - 06-Dec-2023 20:48:35 - [ 7] Visit: 03 Visit Requirements: ORIENT 78D TO 82 D; ORIENT 168D TO 172 D; ORIENT 258D TO 262 D; ORIENT 348D TO 352 D; SEQ 01, 02, 03 WITHIN 7 D On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 SN-1987A WFC3/UVI ACCUM UVIS2-C1K F502N CR-SPLIT=NO, FLASH=16 1 700 S PATTERN 1 1-2 S 1C-SUB (2800 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 SN-1987A WFC3/UVI ACCUM UVIS2-C1K F502N CR-SPLIT=NO, FLASH=16 1 700 S S 1C-SUB (2800 S) ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ SN-1987A 1 WFC3/UVI ACCUM UVIS2-C1 F502N 1 none none none 1 N/A S K1C-SUB SN-1987A 1 WFC3/UVI ACCUM UVIS2-C1 F502N 2 none none none 1 N/A S K1C-SUB SN-1987A 1 WFC3/UVI ACCUM UVIS2-C1 F502N 3 none none none 2 N/A S K1C-SUB SN-1987A 1 WFC3/UVI ACCUM UVIS2-C1 F502N 4 none none none 2 N/A S K1C-SUB SN-1987A 2 WFC3/UVI ACCUM UVIS2-C1 F502N 1 none none none 1 N/A S K1C-SUB SN-1987A 2 WFC3/UVI ACCUM UVIS2-C1 F502N 2 none none none 1 N/A S K1C-SUB SN-1987A 2 WFC3/UVI ACCUM UVIS2-C1 F502N 3 none none none 2 N/A S K1C-SUB SN-1987A 2 WFC3/UVI ACCUM UVIS2-C1 F502N 4 none none none 2 N/A S K1C-SUB 16996( 6) - 06-Dec-2023 20:48:35 - [ 8] Visit: 11 Visit Requirements: SCHED 70%; ORIENT 78D TO 82 D; ORIENT 168D TO 172 D; ORIENT 258D TO 262 D; ORIENT 348D TO 352 D; BEFORE 15-MAR-2024:00:00:00; SEQ 11, 12, 13, 14 WITHIN 7 D On Hold Comments: Additional Comments: Repeat of failed visit 01 Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 SN-1987A WFC3/UVI ACCUM UVIS2-C1K F438W FLASH=14 1 300 S PATTERN 1 1-2 S 1C-SUB see below (1040 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 SN-1987A WFC3/UVI ACCUM UVIS2-C1K F625W FLASH=9 1 270 S S 1C-SUB see below (920 S) ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ SN-1987A 1 WFC3/UVI ACCUM UVIS2-C1 F438W 1 none none none 1 260.0 S S K1C-SUB SN-1987A 1 WFC3/UVI ACCUM UVIS2-C1 F438W 2 none none none 1 260.0 S S K1C-SUB SN-1987A 1 WFC3/UVI ACCUM UVIS2-C1 F438W 3 none none none 1 260.0 S S K1C-SUB SN-1987A 1 WFC3/UVI ACCUM UVIS2-C1 F438W 4 none none none 1 260.0 S S K1C-SUB SN-1987A 2 WFC3/UVI ACCUM UVIS2-C1 F625W 1 none none none 1 230.0 S S K1C-SUB SN-1987A 2 WFC3/UVI ACCUM UVIS2-C1 F625W 2 none none none 1 230.0 S S K1C-SUB SN-1987A 2 WFC3/UVI ACCUM UVIS2-C1 F625W 3 none none none 1 230.0 S S K1C-SUB SN-1987A 2 WFC3/UVI ACCUM UVIS2-C1 F625W 4 none none none 1 230.0 S S K1C-SUB 16996( 6) - 06-Dec-2023 20:48:35 - [ 9] Visit: 12 Visit Requirements: SCHED 70%; ORIENT 78D TO 82 D; ORIENT 168D TO 172 D; ORIENT 258D TO 262 D; ORIENT 348D TO 352 D On Hold Comments: Additional Comments: Repeat of failed visit 02 Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 SN-1987A WFC3/UVI ACCUM UVIS2-C1K F657N CR-SPLIT=NO, FLASH=15 1 700 S PATTERN 1 1 S 1C-SUB see below (2472 S) ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ SN-1987A 1 WFC3/UVI ACCUM UVIS2-C1 F657N 1 none none none 1 618.0 S S K1C-SUB SN-1987A 1 WFC3/UVI ACCUM UVIS2-C1 F657N 2 none none none 1 618.0 S S K1C-SUB SN-1987A 1 WFC3/UVI ACCUM UVIS2-C1 F657N 3 none none none 1 618.0 S S K1C-SUB SN-1987A 1 WFC3/UVI ACCUM UVIS2-C1 F657N 4 none none none 1 618.0 S S K1C-SUB 16996( 6) - 06-Dec-2023 20:48:35 - [ 10] Visit: 13 Visit Requirements: SCHED 70%; ORIENT 78D TO 82 D; ORIENT 168D TO 172 D; ORIENT 258D TO 262 D; ORIENT 348D TO 352 D On Hold Comments: Additional Comments: Repeat of failed visit 03 Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 SN-1987A WFC3/UVI ACCUM UVIS2-C1K F502N CR-SPLIT=NO, FLASH=16 1 700 S PATTERN 1 1 S 1C-SUB see below (2472 S) ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ SN-1987A 1 WFC3/UVI ACCUM UVIS2-C1 F502N 1 none none none 1 618.0 S S K1C-SUB SN-1987A 1 WFC3/UVI ACCUM UVIS2-C1 F502N 2 none none none 1 618.0 S S K1C-SUB SN-1987A 1 WFC3/UVI ACCUM UVIS2-C1 F502N 3 none none none 1 618.0 S S K1C-SUB SN-1987A 1 WFC3/UVI ACCUM UVIS2-C1 F502N 4 none none none 1 618.0 S S K1C-SUB 16996( 6) - 06-Dec-2023 20:48:35 - [ 11] Visit: 14 Visit Requirements: SCHED 70%; ORIENT 78D TO 82 D; ORIENT 168D TO 172 D; ORIENT 258D TO 262 D; ORIENT 348D TO 352 D On Hold Comments: Additional Comments: Repeat of failed visit 03 Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 SN-1987A WFC3/UVI ACCUM UVIS2-C1K F502N CR-SPLIT=NO, FLASH=16 1 700 S PATTERN 1 1 S 1C-SUB see below (2472 S) ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ SN-1987A 1 WFC3/UVI ACCUM UVIS2-C1 F502N 1 none none none 1 618.0 S S K1C-SUB SN-1987A 1 WFC3/UVI ACCUM UVIS2-C1 F502N 2 none none none 1 618.0 S S K1C-SUB SN-1987A 1 WFC3/UVI ACCUM UVIS2-C1 F502N 3 none none none 1 618.0 S S K1C-SUB SN-1987A 1 WFC3/UVI ACCUM UVIS2-C1 F502N 4 none none none 1 618.0 S S K1C-SUB 16996( 6) - 06-Dec-2023 20:48:35 - [ 12] Summary Form for Proposal 16996 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures UVIS2-C1K1C-SUB ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFC3/UVIS ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters CR-SPLIT=NO, FLASH=14, FLASH=15, FLASH=16, FLASH=9 ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements BEFORE 15-MAR-2024:00:00:00, BETWEEN 01-MAY-2023:00:00:00 AND 30-SEP-2023, ORIENT 168D TO 172 D, ORIENT 258D TO 262 D, ORIENT 348D TO 352 D, ORIENT 78D TO 82 D, PATTERN 1 1, PATTERN 1 1-2, SCHED 70%, SEQ 01, 02, 03 WITHIN 7 D, SEQ 11, 12, 13, 14 WITHIN 7 D ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F438W, F502N, F625W, F657N ------------------------------------------------------------------------------------------------------------------------------------ Target Names SN-1987A ------------------------------------------------------------------------------------------------------------------------------------