11180( 2) - 05/10/07 11:38 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 11180 Version: 2 Check-in Time: 10-May-2007 15:38:28 STScI Edit Number: 0 Title The Morphology of the Post-Red Supergiant IRC+10420's Circumstellar Ejecta ------------------------------------------------------------------------------------ Type Cycle Parallel Pointing Tolerance GO 16 ------------------------------------------------------------------------------------ Investigators Contact? PI: Dr. Roberta M. Humphreys University of Minnesota - Twin Cities CoI: Dr. Kris Davidson University of Minnesota - Twin Cities N CoI: Dr. Terry J. Jones University of Minnesota - Twin Cities N ------------------------------------------------------------------------------------ Abstract The extremely luminous post-red supergiant and powerful OH/IR source IRC +10420 is surrounded by a complex circumstellar nebula. Numerous small condensations, arcs, jet-like rays of knots, and intriguing semi-circular structures are easily visible in our previous WFPC2 images. We have suggested that these spatially recognizable features may be evidence for episodic mass loss events possibly from localized active regions. We now propose to obtain second epoch WFPC2 images with the Planetary Camera to measure the transverse motions of these ejecta. Spatially resolved spectra from STIS showed that the embedded arcs are kinematically distinct from the spherically expanding diffuse nebulosity. The transverse motions in combination with radial velocities from the STIS spectra, will let us determine the morphology of IRC +10420's nebula and the structures embedded in it, its mass loss history, and provide clues to the mass loss mechanism responsible for the discrete ejections. ------------------------------------------------------------------------------------ 11180( 2) - 05/10/07 11:38 - [ 2] Observations Description ------------------------ Our proposed second epoch images will repeat the 1996 obervations with the Planetary Camera. We used the F547M and F467M filters with a wide range of exposure times to image the bright embedded star, material close to it, and the faint outer nebulosity. These observations take one orbit. In addition to repeating the 1996 imaging we also propose to add a series of images with the F675W filter with a range of integration times, including a long exposure intended to look or a faint outer reflection shell at about 8 arcsec reported by Kastner & Weintraub (1995) at 1.25 microns. This feature was not visible in our first epoch blue and visual images, and at its distance from the star, it may be a remnant of a prior red supergiant stage. The F675W filter will be dominated by the flux of IRC +10420's very strong Halpha emission line and so will in effect be an Halpha image. However, since IRC +10420 is a reflection nebula we are not trying to separate the Halpha emission from the continuum. We are also adding a series of exposures with the F1042M filter. The images of VY CMa (Smith et al 2001) with this filter yielded a different view of the ejecta showing the distribution of the reddest and dustiest features. We don't know what this may show for IRC +10420, but its 2 micron image showed evidence for bipolarity not apparent in the visual HST images and the 8 arcsec shell was detected at 1.25 microns. The F675W and F1042M images together will take one additional orbit. Real Time Justification ----------------------- Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ 11180( 2) - 05/10/07 11:38 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 IRC+10420 STAR, A4-A9 III-I RA=19H26M48.0300S +/- 0.1", J2000 V = 11.0+/-0.5 DEC=+11D21'16.70" +/- 1" B-V = 2.7 Reference Frame: Other: SIMBAD Comments: This object was generated by the targetselector and retrieved from the SIMBAD database. 11180( 2) - 05/10/07 11:38 - [ 4] Patterns ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 1 Primary_Pattern Secondary_Pattern Pattern_Type WFPC2-LINE Pattern_Purpose DITHER Number_Of_Points 3 Point_Spacing 0.3535 Line_Spacing Coordinate_Frame POS-TARG Pattern_Orient 45.0 Angle_Between_Sides Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 2 Primary_Pattern Secondary_Pattern Pattern_Type WFPC2-LINE Pattern_Purpose DITHER Number_Of_Points 2 Point_Spacing 0.322 Line_Spacing Coordinate_Frame POS-TARG Pattern_Orient 45.0 Angle_Between_Sides Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 3 Primary_Pattern Secondary_Pattern Pattern_Type WFPC2-LINE Pattern_Purpose DITHER Number_Of_Points 2 Point_Spacing 0.161 Line_Spacing Coordinate_Frame POS-TARG Pattern_Orient 45.0 Angle_Between_Sides Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ 11180( 2) - 05/10/07 11:38 - [ 5] Visit: 01 Visit Priority: Visit Requirements: 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| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 IRC+10420 WFPC2 IMAGE PC1 F467M 1 12 S Comments: Short exposure to avoid bleeding of central star. ------------------------------------------------------------------------------------------------------------------------------------ 2 IRC+10420 WFPC2 IMAGE PC1 F467M 1 30 S PATTERN 3 2 Comments: two 30s exposures dithered to duplicate the dither used in GO 6475. ------------------------------------------------------------------------------------------------------------------------------------ 3 IRC+10420 WFPC2 IMAGE PC1 F467M 1 140 S PATTERN 2 3 Comments: two 140s exposures dithered with same spacing used in GO 6475. ------------------------------------------------------------------------------------------------------------------------------------ 4 IRC+10420 WFPC2 IMAGE PC1 F547M 1 0.5 S Comments: Short exposure to avoid bleeding by central star. ------------------------------------------------------------------------------------------------------------------------------------ 5 IRC+10420 WFPC2 IMAGE PC1 F547M 1 3 S ------------------------------------------------------------------------------------------------------------------------------------ 6 IRC+10420 WFPC2 IMAGE PC1 F547M 2 10 S ------------------------------------------------------------------------------------------------------------------------------------ 7 IRC+10420 WFPC2 IMAGE PC1 F547M 1 40 S ------------------------------------------------------------------------------------------------------------------------------------ 8 IRC+10420 WFPC2 IMAGE PC1 F547M CR-SPLIT=DEF 1 300 S ------------------------------------------------------------------------------------------------------------------------------------ 9 IRC+10420 WFPC2 IMAGE PC1 F675W 1 0.5 S Comments: Short exposure to avoid bleeding by central star ------------------------------------------------------------------------------------------------------------------------------------ 10 IRC+10420 WFPC2 IMAGE PC1 F675W 1 5 S ------------------------------------------------------------------------------------------------------------------------------------ 11 IRC+10420 WFPC2 IMAGE PC1 F675W 1 30 S PATTERN 1 11 Comments: Three 30s exposures in a line dither pattern ------------------------------------------------------------------------------------------------------------------------------------ 12 IRC+10420 WFPC2 IMAGE PC1 F675W CR-SPLIT=DEF 1 600 S ------------------------------------------------------------------------------------------------------------------------------------ 13 IRC+10420 WFPC2 IMAGE PC1 F1042M 1 0.5 S Comments: Short exposure to avoid bleeding ------------------------------------------------------------------------------------------------------------------------------------ 14 IRC+10420 WFPC2 IMAGE PC1 F1042M 1 5 S ------------------------------------------------------------------------------------------------------------------------------------ 11180( 2) - 05/10/07 11:38 - [ 6] Exposures ----------------------------------------------------------------------------------------------------------------------------------- Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| | Requirements ----------------------------------------------------------------------------------------------------------------------------------- 15 IRC+10420 WFPC2 IMAGE PC1 F1042M 1 30 S ------------------------------------------------------------------------------------------------------------------------------------ 16 IRC+10420 WFPC2 IMAGE PC1 F1042M 1 100 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 | ------------------------------------------------------------------------------------------------------------------------------------ IRC+10420 1 WFPC2 IMAGE PC1 F467M none none none none 1 N/A IRC+10420 2 WFPC2 IMAGE PC1 F467M 1 none none none 1 N/A IRC+10420 2 WFPC2 IMAGE PC1 F467M 2 none none none 1 N/A IRC+10420 3 WFPC2 IMAGE PC1 F467M 1 none none none 1 N/A IRC+10420 3 WFPC2 IMAGE PC1 F467M 2 none none none 1 N/A IRC+10420 4 WFPC2 IMAGE PC1 F547M none none none none 1 N/A IRC+10420 5 WFPC2 IMAGE PC1 F547M none none none none 1 N/A IRC+10420 6 WFPC2 IMAGE PC1 F547M none none 1 none 1 N/A IRC+10420 6 WFPC2 IMAGE PC1 F547M none none 2 none 1 N/A IRC+10420 7 WFPC2 IMAGE PC1 F547M none none none none 1 N/A IRC+10420 8 WFPC2 IMAGE PC1 F547M none none none none 1 N/A IRC+10420 9 WFPC2 IMAGE PC1 F675W none none none none 2 N/A IRC+10420 10 WFPC2 IMAGE PC1 F675W none none none none 2 N/A IRC+10420 11 WFPC2 IMAGE PC1 F675W 1 none none none 2 N/A IRC+10420 11 WFPC2 IMAGE PC1 F675W 2 none none none 2 N/A IRC+10420 11 WFPC2 IMAGE PC1 F675W 3 none none none 2 N/A IRC+10420 12 WFPC2 IMAGE PC1 F675W none none none none 2 N/A IRC+10420 13 WFPC2 IMAGE PC1 F1042M none none none none 2 N/A IRC+10420 14 WFPC2 IMAGE PC1 F1042M none none none none 2 N/A IRC+10420 15 WFPC2 IMAGE PC1 F1042M none none none none 2 N/A IRC+10420 16 WFPC2 IMAGE PC1 F1042M none none none none 2 N/A 11180( 2) - 05/10/07 11:38 - [ 7] Summary Form for Proposal 11180 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures PC1 ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFPC2 ------------------------------------------------------------------------------------------------------------------------------------ Opmodes IMAGE ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters CR-SPLIT=DEF ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements PATTERN 3 2; PATTERN 2 3; PATTERN 1 11; ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F467M F547M F675W F1042M ------------------------------------------------------------------------------------------------------------------------------------ Target Names IRC+10420 ------------------------------------------------------------------------------------------------------------------------------------