14157( 3) - 03-Mar-2016 15:10:58 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 14157 Version: 3 Check-in Time: 03-Mar-2016 15:10:58 STScI Edit Number: 0 Title Testing Model Atmospheres with the Coldest Known Brown Dwarf ------------------------------------------------------------------------------------ Type Cycle GO 23 ------------------------------------------------------------------------------------ Investigators Contact? PI: Prof. Kevin Luhman The Pennsylvania State University Y CoI: Mr. Taran Esplin The Pennsylvania State University N ------------------------------------------------------------------------------------ Abstract Last year, we discovered a brown dwarf, WISE 0855-0714, that has a distance of 2.3 pc and a temperature of ~250 K, making it the 4th closest neighbor of the Sun and the coldest known brown dwarf. Because of its extreme proximity and temperature, it represents an unparallaled laboratory for studying planet-like atmospheres in an unexplored temperature regime. In Cycle 22, we obtained images of WISE 0855-0714 in the single most sensitive band of WFC3 for brown dwarfs (F110W) to assess the feasibility of spectroscopy and multi-band photometry, and to begin using it to test the colors predicted by model atmospheres. We have detected WISE 0855-0714 in those data, and the resulting photometry indicates that it is too faint for spectroscopy, but that photometry in additional HST bands is feasible. Therefore, we propose to observe WISE 0855-0714 with ACS and WFC3 in three bands that are well-suited for testing and discriminating between competing models of very cold atmospheres. ------------------------------------------------------------------------------------ Observations Description ------------------------ This program consists of WFC3/IR and ACS/WFC images in F105W, F127M, and F850LP of a single faint point source during 18 orbits (6 orbits per filter). The observations have been designed to maximize the total exposure time, optimize the spatial resolution, and provide sufficient flexibility for scheduling. For each of the three filters, the images will be obtained through three identical two-orbit visits. In each orbit, one exposure (SPARS100, NSAMP=10, 900 sec for WFC3; 810 sec for ACS) will be collected at each position in a three-point dither pattern. In each visit, the dither patterns in the two orbits will be offset from each other by 3.5 pixels along the x-axis of the array. The target will be observed at the IR and WFC1-1K apertures for WFC3 and ACS, respectively. ------------------------------------------------------------------------------------ 14157( 3) - 03-Mar-2016 15:10:58 - [ 2] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 WISE0855-071 STAR, BROWN DWARF RA=08H55M7.8289S +/- 0.1", J2000 V = 35 4 DEC=-07D14'38.75" +/- 0.1" Reference Frame: ICRS Extended: NO Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 2016 -0.5443449912234706 0.7 0.433 ------------------------------------------------------------------------------------------------------------------------------------ 14157( 3) - 03-Mar-2016 15:10:58 - [ 3] Patterns ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 1 Primary_Pattern Secondary_Pattern Pattern_Type LINE WFC3-IR-DITHER-LINE-3PT Pattern_Purpose DITHER DITHER Number_Of_Points 2 3 Point_Spacing 0.4725 0.605 Line_Spacing Coordinate_Frame POS-TARG POS-TARG Pattern_Orient 0 41.788 Angle_Between_Sides Center_Pattern NO NO ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 2 Primary_Pattern Secondary_Pattern Pattern_Type LINE ACS-WFC-DITHER-LINE Pattern_Purpose DITHER DITHER Number_Of_Points 2 3 Point_Spacing 0.1726 0.170 Line_Spacing Coordinate_Frame POS-TARG POS-TARG Pattern_Orient 0 47.23 Angle_Between_Sides Center_Pattern NO NO ------------------------------------------------------------------------------------------------------------------------------------ 14157( 3) - 03-Mar-2016 15:10:58 - [ 4] Visit: 01 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| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 WISE0855-07 WFC3/IR MULTIAC IR F105W NSAMP=10, SAMP-SEQ=SPARS100 1 DEF PATTERN 1 1 14 CUM (5417.611 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 | ------------------------------------------------------------------------------------------------------------------------------------ WISE0855-0714 1 WFC3/IR MULTIAC IR F105W 1 1 none none 1 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F105W 1 2 none none 1 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F105W 1 3 none none 1 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F105W 2 1 none none 2 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F105W 2 2 none none 2 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F105W 2 3 none none 2 N/A CUM 14157( 3) - 03-Mar-2016 15:10:58 - [ 5] Visit: 02 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| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 WISE0855-07 WFC3/IR MULTIAC IR F105W NSAMP=10, SAMP-SEQ=SPARS100 1 DEF PATTERN 1 1 14 CUM (5417.611 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 | ------------------------------------------------------------------------------------------------------------------------------------ WISE0855-0714 1 WFC3/IR MULTIAC IR F105W 1 1 none none 1 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F105W 1 2 none none 1 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F105W 1 3 none none 1 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F105W 2 1 none none 2 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F105W 2 2 none none 2 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F105W 2 3 none none 2 N/A CUM 14157( 3) - 03-Mar-2016 15:10:58 - [ 6] Visit: 03 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| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 WISE0855-07 WFC3/IR MULTIAC IR F105W NSAMP=10, SAMP-SEQ=SPARS100 1 DEF PATTERN 1 1 14 CUM (5417.611 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 | ------------------------------------------------------------------------------------------------------------------------------------ WISE0855-0714 1 WFC3/IR MULTIAC IR F105W 1 1 none none 1 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F105W 1 2 none none 1 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F105W 1 3 none none 1 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F105W 2 1 none none 2 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F105W 2 2 none none 2 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F105W 2 3 none none 2 N/A CUM 14157( 3) - 03-Mar-2016 15:10:58 - [ 7] Visit: 04 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| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 WISE0855-07 WFC3/IR MULTIAC IR F127M NSAMP=10, SAMP-SEQ=SPARS100 1 DEF PATTERN 1 1 14 CUM (5417.611 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 | ------------------------------------------------------------------------------------------------------------------------------------ WISE0855-0714 1 WFC3/IR MULTIAC IR F127M 1 1 none none 1 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F127M 1 2 none none 1 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F127M 1 3 none none 1 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F127M 2 1 none none 2 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F127M 2 2 none none 2 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F127M 2 3 none none 2 N/A CUM 14157( 3) - 03-Mar-2016 15:10:58 - [ 8] Visit: 05 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| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 WISE0855-07 WFC3/IR MULTIAC IR F127M NSAMP=10, SAMP-SEQ=SPARS100 1 DEF PATTERN 1 1 14 CUM (5417.611 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 | ------------------------------------------------------------------------------------------------------------------------------------ WISE0855-0714 1 WFC3/IR MULTIAC IR F127M 1 1 none none 1 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F127M 1 2 none none 1 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F127M 1 3 none none 1 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F127M 2 1 none none 2 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F127M 2 2 none none 2 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F127M 2 3 none none 2 N/A CUM 14157( 3) - 03-Mar-2016 15:10:58 - [ 9] Visit: 06 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| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 WISE0855-07 WFC3/IR MULTIAC IR F127M NSAMP=10, SAMP-SEQ=SPARS100 1 DEF PATTERN 1 1 14 CUM (5417.611 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 | ------------------------------------------------------------------------------------------------------------------------------------ WISE0855-0714 1 WFC3/IR MULTIAC IR F127M 1 1 none none 1 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F127M 1 2 none none 1 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F127M 1 3 none none 1 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F127M 2 1 none none 2 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F127M 2 2 none none 2 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F127M 2 3 none none 2 N/A CUM 14157( 3) - 03-Mar-2016 15:10:58 - [ 10] Visit: 07 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| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 WISE0855-07 ACS/WFC ACCUM WFC1-CTE F850LP 1 810 S PATTERN 2 1 14 see below (4878 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 | ------------------------------------------------------------------------------------------------------------------------------------ WISE0855-0714 1 ACS/WFC ACCUM WFC1-CTE F850LP 1 1 none none 1 781.0 S WISE0855-0714 1 ACS/WFC ACCUM WFC1-CTE F850LP 1 2 none none 1 781.0 S WISE0855-0714 1 ACS/WFC ACCUM WFC1-CTE F850LP 1 3 none none 1 781.0 S WISE0855-0714 1 ACS/WFC ACCUM WFC1-CTE F850LP 2 1 none none 2 845.0 S WISE0855-0714 1 ACS/WFC ACCUM WFC1-CTE F850LP 2 2 none none 2 845.0 S WISE0855-0714 1 ACS/WFC ACCUM WFC1-CTE F850LP 2 3 none none 2 845.0 S 14157( 3) - 03-Mar-2016 15:10:58 - [ 11] Visit: 08 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| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 WISE0855-07 ACS/WFC ACCUM WFC1-CTE F850LP 1 810 S PATTERN 2 1 14 see below (4878 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 | ------------------------------------------------------------------------------------------------------------------------------------ WISE0855-0714 1 ACS/WFC ACCUM WFC1-CTE F850LP 1 1 none none 1 781.0 S WISE0855-0714 1 ACS/WFC ACCUM WFC1-CTE F850LP 1 2 none none 1 781.0 S WISE0855-0714 1 ACS/WFC ACCUM WFC1-CTE F850LP 1 3 none none 1 781.0 S WISE0855-0714 1 ACS/WFC ACCUM WFC1-CTE F850LP 2 1 none none 2 845.0 S WISE0855-0714 1 ACS/WFC ACCUM WFC1-CTE F850LP 2 2 none none 2 845.0 S WISE0855-0714 1 ACS/WFC ACCUM WFC1-CTE F850LP 2 3 none none 2 845.0 S 14157( 3) - 03-Mar-2016 15:10:58 - [ 12] Visit: 09 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| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 WISE0855-07 ACS/WFC ACCUM WFC1-CTE F850LP 1 810 S PATTERN 2 1 14 see below (4878 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 | ------------------------------------------------------------------------------------------------------------------------------------ WISE0855-0714 1 ACS/WFC ACCUM WFC1-CTE F850LP 1 1 none none 1 781.0 S WISE0855-0714 1 ACS/WFC ACCUM WFC1-CTE F850LP 1 2 none none 1 781.0 S WISE0855-0714 1 ACS/WFC ACCUM WFC1-CTE F850LP 1 3 none none 1 781.0 S WISE0855-0714 1 ACS/WFC ACCUM WFC1-CTE F850LP 2 1 none none 2 845.0 S WISE0855-0714 1 ACS/WFC ACCUM WFC1-CTE F850LP 2 2 none none 2 845.0 S WISE0855-0714 1 ACS/WFC ACCUM WFC1-CTE F850LP 2 3 none none 2 845.0 S 14157( 3) - 03-Mar-2016 15:10:58 - [ 13] Summary Form for Proposal 14157 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures IR, WFC1-CTE ------------------------------------------------------------------------------------------------------------------------------------ Configurations ACS/WFC, WFC3/IR ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACCUM, MULTIACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters NSAMP=10, SAMP-SEQ=SPARS100 ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements PATTERN 1 1, PATTERN 2 1 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F105W, F127M, F850LP ------------------------------------------------------------------------------------------------------------------------------------ Target Names WISE0855-0714 ------------------------------------------------------------------------------------------------------------------------------------