15289( 3) - 15-Feb-2018 21:08:59 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 15289 Version: 3 Check-in Time: 15-Feb-2018 21:08:59 STScI Edit Number: 0 Title Imaging Shock Fronts in the Outer Ejecta of Eta Carinae ------------------------------------------------------------------------------------ Type Cycle GO 25 ------------------------------------------------------------------------------------ Investigators Contact? PI: Dr. Nathan Smith University of Arizona Y CoI: Dr. Jon A. Morse BoldlyGo Institute N ------------------------------------------------------------------------------------ Abstract Although Eta Car has been imaged many times with HST to monitor the central star and the bright Homunculus Nebula, we propose the first WFC3 imaging of Eta Car to study the more extended "Outer Ejecta" from previous eruptions. WFC3 has two key filters that have not been used before to image Eta Car, which will provide critical physical information about its eruptive history: (1) F280N with WFC3/UVIS will produce the first Mg II 2800 image of Eta Car, the sharpest image of its complex Outer Ejecta, and will unambiguously trace shock fronts, and (2) F126N with WFC3/IR will sample [Fe II] 12567 arising in the densest post-shock gas. Eta Car is surrounded by a bright, soft X-ray shell seen in Chandra images, which arises from the fastest 1840s ejecta overtaking slower older material. Our recent proper motion measurements show that the outer knots were ejected in two outbursts several hundred years before the 1840s eruption, and spectroscopy of light echoes has recently revealed extremely fast ejecta during the 1840s that indicate an explosive event. Were those previous eruptions explosive as well? If so, were they as energetic, did they also have such fast ejecta, and did they have the same geometry? The structure and excitation of the Outer Ejecta hold unique clues for reconstructing Eta Car's violent mass loss history. The locations of shock fronts in circumstellar material provide critical information, because they identify past discontinuities in the mass loss. This is one of the only ways to investigate the long term (i.e. centuries) evolution and duty cycle of eruptive mass loss in the most massive stars. ------------------------------------------------------------------------------------ Observations Description ------------------------ These observations aim to obtain an image of the extended Mg II 2800 emission and the [Fe II] 1.2567 um emission of the Outer Ejecta nebulosity around the Homunculus of Eta Carinae. For the MgII 2800 line, we use the WFC3/UVIS F280N filter. For the near-IR [Fe II] emission, we use the WFC3/IR F126N emission line filter and the F130N filter for off-line continuum to subtract. The IR images will use a 4-point dither pattern with a gap in the middel to avoid the central star, which is extremely bright in the IR. ------------------------------------------------------------------------------------ 15289( 3) - 15-Feb-2018 21:08:59 - [ 2] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 ETA-CAR STAR, CIRCUMSTELLAR RA=10H45M3.5460S, J2000 V = 6.21 MATTER, EMISSION LINE DEC=-59D41'3.95" NEBULA, EMISSION LINE STAR, ETA CARINAE STAR, LUMINOUS BLUE VARIABLE Reference Frame: Other: SIMBAD Extended: YES Comments: This object was generated by the targetselector and retrieved from the SIMBAD database. ------------------------------------------------------------------------------------------------------------------------------------ 15289( 3) - 15-Feb-2018 21:08:59 - [ 3] Patterns ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 1 Primary_Pattern Secondary_Pattern Pattern_Type WFC3-UVIS-MOS-DITH-LINE Pattern_Purpose MOSAIC Number_Of_Points 3 Point_Spacing 2.4 Line_Spacing Coordinate_Frame POS-TARG Pattern_Orient 85.754 Angle_Between_Sides Center_Pattern YES ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 2 Primary_Pattern Secondary_Pattern Pattern_Type LINE LINE Pattern_Purpose MOSAIC MOSAIC Number_Of_Points 2 2 Point_Spacing 94 104 Line_Spacing Coordinate_Frame POS-TARG POS-TARG Pattern_Orient 40 134 Angle_Between_Sides Center_Pattern YES YES ------------------------------------------------------------------------------------------------------------------------------------ 15289( 3) - 15-Feb-2018 21:08:59 - [ 4] Visit: 01 (MgII) Visit Requirements: CVZ; ORIENT 345D TO 359 D On Hold Comments: Additional Comments: MgII line emission image of the Outer Ejecta. 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 ETA-CAR WFC3/UVI ACCUM UVIS-CENT F280N CR-SPLIT=2, FLASH=2.0 1 1310 S PATTERN 1 1 S ER (3930 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 | ------------------------------------------------------------------------------------------------------------------------------------ ETA-CAR 1 WFC3/UVI ACCUM UVIS-CEN F280N 1 none none 1 1 N/A S TER ETA-CAR 1 WFC3/UVI ACCUM UVIS-CEN F280N 1 none none 2 1 N/A S TER ETA-CAR 1 WFC3/UVI ACCUM UVIS-CEN F280N 2 none none 1 1 N/A S TER ETA-CAR 1 WFC3/UVI ACCUM UVIS-CEN F280N 2 none none 2 1 N/A S TER ETA-CAR 1 WFC3/UVI ACCUM UVIS-CEN F280N 3 none none 1 1 N/A S TER ETA-CAR 1 WFC3/UVI ACCUM UVIS-CEN F280N 3 none none 2 1 N/A S TER 15289( 3) - 15-Feb-2018 21:08:59 - [ 5] Visit: 02 (FeII) Visit Requirements: DROP TO GYRO IF NECESSARY ; CVZ; ORIENT 350D TO 5 D On Hold Comments: Additional Comments: FeII and continuum images of Outer Ejecta. 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 ETA-CAR WFC3/IR MULTIAC IR-FIX F126N NSAMP=15, SAMP-SEQ=STEP50 1 DEF PATTERN 2 1-2 CUM (1996.937 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 ETA-CAR WFC3/IR MULTIAC IR-FIX F130N NSAMP=15, SAMP-SEQ=STEP50 1 DEF CUM (1996.937 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 | ------------------------------------------------------------------------------------------------------------------------------------ ETA-CAR 1 WFC3/IR MULTIAC IR-FIX F126N 1 1 none none 1 N/A CUM ETA-CAR 1 WFC3/IR MULTIAC IR-FIX F126N 1 2 none none 1 N/A CUM ETA-CAR 1 WFC3/IR MULTIAC IR-FIX F126N 2 1 none none 1 N/A CUM ETA-CAR 1 WFC3/IR MULTIAC IR-FIX F126N 2 2 none none 1 N/A CUM ETA-CAR 2 WFC3/IR MULTIAC IR-FIX F130N 1 1 none none 1 N/A CUM ETA-CAR 2 WFC3/IR MULTIAC IR-FIX F130N 1 2 none none 1 N/A CUM ETA-CAR 2 WFC3/IR MULTIAC IR-FIX F130N 2 1 none none 1 N/A CUM ETA-CAR 2 WFC3/IR MULTIAC IR-FIX F130N 2 2 none none 1 N/A CUM 15289( 3) - 15-Feb-2018 21:08:59 - [ 6] Summary Form for Proposal 15289 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures IR-FIX, UVIS-CENTER ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFC3/IR, WFC3/UVIS ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACCUM, MULTIACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters CR-SPLIT=2, FLASH=2.0, NSAMP=15, SAMP-SEQ=STEP50 ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements CVZ, DROP TO GYRO IF NECESSARY , ORIENT 345D TO 359 D, ORIENT 350D TO 5 D, PATTERN 1 1, PATTERN 2 1-2 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F126N, F130N, F280N ------------------------------------------------------------------------------------------------------------------------------------ Target Names ETA-CAR ------------------------------------------------------------------------------------------------------------------------------------