13802( 3) - 12-Mar-2015 12:27:54 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 13802 Version: 3 Check-in Time: 12-Mar-2015 12:27:54 STScI Edit Number: 0 Title Characterizing the Sun's 4th Closest Neighbor and the Coldest Known Brown Dwarf ------------------------------------------------------------------------------------ Type Cycle GO 22 ------------------------------------------------------------------------------------ Investigators Contact? PI: Prof. Kevin Luhman The Pennsylvania State University Y ------------------------------------------------------------------------------------ Abstract I have conducted a search for high proper motion brown dwarfs using multi-epoch all-sky mid-infrared images from the WISE satellite. Through this work, I have discovered an object with a parallactic distance of 2.2 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. I propose to obtain deep near-IR images of this object in the single most sensitive band of WFC3 in order to 1) test the predicted near- to mid-IR colors of the coldest brown dwarfs, 2) assess the feasibility of more detailed observations through multi-band photometry and spectroscopy, 3) improve the accuracy of its parallax measurement, and 4) better constrain its multiplicity. ------------------------------------------------------------------------------------ Observations Description ------------------------ This program consists of WFC3/IR images in F110W of a single faint point source during six orbits. The observations have been designed to maximize the total exposure time, optimize the spatial resolution, and provide sufficient flexibility for scheduling. The images will be obtained through three identical two-orbit visits. In each orbit, one exposure (SPARS100, NSAMP=10, 900 sec) will be collected at each position in a three-point dither pattern (WFC3-IR-DITHER-LINE-3PT). In each visit, the dither patterns in the two orbits will be offset by 3.5 pixels along the x-axis of the array. ------------------------------------------------------------------------------------ 13802( 3) - 12-Mar-2015 12:27:54 - [ 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=08H55M8.9000S +/- 0.1", J2000 V = 35 4 DEC=-07D14'40.02" +/- 0.1" Reference Frame: ICRS Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 2014.052 -0.5416572917439062 0.69 0.455 ------------------------------------------------------------------------------------------------------------------------------------ 13802( 3) - 12-Mar-2015 12:27:54 - [ 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 ------------------------------------------------------------------------------------------------------------------------------------ 13802( 3) - 12-Mar-2015 12:27:54 - [ 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 F110W 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 F110W 1 1 none none 1 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F110W 1 2 none none 1 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F110W 1 3 none none 1 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F110W 2 1 none none 2 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F110W 2 2 none none 2 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F110W 2 3 none none 2 N/A CUM 13802( 3) - 12-Mar-2015 12:27:54 - [ 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 F110W 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 F110W 1 1 none none 1 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F110W 1 2 none none 1 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F110W 1 3 none none 1 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F110W 2 1 none none 2 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F110W 2 2 none none 2 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F110W 2 3 none none 2 N/A CUM 13802( 3) - 12-Mar-2015 12:27:54 - [ 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 F110W 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 F110W 1 1 none none 1 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F110W 1 2 none none 1 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F110W 1 3 none none 1 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F110W 2 1 none none 2 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F110W 2 2 none none 2 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F110W 2 3 none none 2 N/A CUM 13802( 3) - 12-Mar-2015 12:27:54 - [ 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 F110W 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 F110W 1 1 none none 1 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F110W 1 2 none none 1 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F110W 1 3 none none 1 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F110W 2 1 none none 2 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F110W 2 2 none none 2 N/A CUM WISE0855-0714 1 WFC3/IR MULTIAC IR F110W 2 3 none none 2 N/A CUM 13802( 3) - 12-Mar-2015 12:27:54 - [ 8] Summary Form for Proposal 13802 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures IR ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFC3/IR ------------------------------------------------------------------------------------------------------------------------------------ Opmodes MULTIACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters NSAMP=10, SAMP-SEQ=SPARS100 ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements PATTERN 1 1 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F110W ------------------------------------------------------------------------------------------------------------------------------------ Target Names WISE0855-0714 ------------------------------------------------------------------------------------------------------------------------------------