10477( 4) - 09/07/05 18:32 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 10477 Version: 4 Check-in Time: 07-Sep-2005 22:31:41 Title The Masses of the O-type Binary 15 Monocerotis ------------------------------------------------------------------------------------ Type Cycle Parallel Pointing Tolerance GO 14 ------------------------------------------------------------------------------------ Investigators Contact? PI: Dr. Douglas R. Gies Georgia State University Research Foundation CoI: Dr. William G. Bagnuolo Jr. Georgia State University Research N Foundation CoI: Dr. William I. Hartkopf United States Naval Observatory N CoI: Dr. Brian D. Mason United States Naval Observatory N CoI: Dr. Harold A. McAlister Georgia State University Research N Foundation CoI: Dr. Edmund Nelan Space Telescope Science Institute N CoI: Dr. Debra J. Wallace NASA Goddard Space Flight Center N ------------------------------------------------------------------------------------ Abstract The O-type star 15 Mon (HD 47839) was recently discovered to be an astrometric and spectroscopic binary with a period of 25 years; it is the first known O-star system to bridge the observational gap between the period regimes normally probed by these techniques. An analysis of both the radial velocity curve and astrometric orbit yields the masses of the components and distance to the system. Continuing radial velocity and HST/FGS astrometric measurements will lead to a definitive orbit and yield key information about the masses of O-type stars. FGS TRANS mode measurements of separation, position angle, and magnitude difference (begun in Cycle 5) are needed to link existing speckle observations and anticipated observations with the CHARA Array optical interferometer. In addition, field astrometry measurements (FGS POS mode) will provide the proper motion, parallax, and the binary motion around the center of mass. The POS data will provide an accurate estimate of the mass ratio and an improved estimate of distance, and taken together with the spectroscopic and astrometric orbital data, we will obtain masses for both components accurate to a few percent. ------------------------------------------------------------------------------------ 10477( 4) - 09/07/05 18:32 - [ 2] Observations Description ------------------------ We are continuing our long term program which has successfully run for 2 orbits in each of Cycles 5 - 13. Our first goal is to obtain FGS TRANS mode measurements of the separation, position angle, and magnitude difference of 15 Mon twice each year. We are aiming for a positional accuracy of a few mas and a photometric accuracy of 0.1 mag, both of which have been achieved in recent binary studies with the FGS. Our second goal is to obtain complementary POS mode observations of nearby reference stars so that we can determine the proper motion, parallax, and stellar orbital motion around the system barycenter. We need two visits each year near the times of maximum parallax shift. Because of the relative brightness of the star, the observations will be made with the 5 mag neutral density filter, F5ND. We plan to obtain approximately 10 scans in the TRANS mode of operation which should require approximately 20 minutes exposure time. The remaining 13 minutes in the orbit would be used for POS mode observations. The success of the past observations demonstrates the feasibility of the project. We also need contemporaneous scans of the calibration target, mu Col, but we understand that plans exist for the Observatory to obtain these on a routine basis through future Cycles. Real Time Justification ----------------------- The observations need to be scheduled near the times of maximum parallax shift (early October) and at a later date near small parallax. Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ 10477( 4) - 09/07/05 18:32 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 HD47839 STAR, MAIN SEQUENCE O RA=06H40M58.6600S +/- 0.00005S, J2000 V = 22.0 V = 4.65+/-0.02 DEC=+09D53'44.74" +/- 0.005" Coordinate Source: HIPPARCOS/TYCHO_CATALOGUE Comments: B-V=-0.25+/-0.02, TYPE=O7V((f)), LONG PERIOD BINARY Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 1991.25 -0.000040000 -0.0025 0.0010 2 REF8 CALIBRATION, RA=06H41M4.5300S +/- 1", J2000 V = 0.0 V = 10.36+/-0.1 ASTROMETRIC DEC=+09D54'44.21" +/- 1", PLATE- ID=03QQ Coordinate Source: GUIDE_STAR_CATALOG Comments: #10 IN DATA FROM 2000 TO 2003 3 REF10 CALIBRATION, RA=06H40M59.2900S +/- 1", J2000 V = 0.0 V = 12.4+/-0.1 ASTROMETRIC DEC=+09D55'20.60" +/- 1", PLATE- ID=03QQ Coordinate Source: GUIDE_STAR_CATALOG Comments: #12 IN DATA FROM 2000 TO 2003 4 REF11 CALIBRATION, RA=06H41M0.0000S +/- 1", J2000 V = 0.0 V = 9.88+/-0.1 ASTROMETRIC DEC=+09D52'18.16" +/- 1", PLATE- ID=03QQ Coordinate Source: GUIDE_STAR_CATALOG Comments: #13 IN DATA FROM 2000 TO 2003 5 REF13 CALIBRATION, RA=06H41M11.2000S +/- 1", J2000 V = 0.0 V = 10.0+/-0.1 ASTROMETRIC DEC=+09D52'54.00" +/- 1", PLATE- ID=03QQ Coordinate Source: GUIDE_STAR_CATALOG Comments: #15 IN DATA FROM 2000 TO 2003 6 REF14 CALIBRATION, RA=06H41M10.2000S +/- 1", J2000 V = 0.0 V = 9.3+/-0.1 ASTROMETRIC DEC=+09D53'2.00" +/- 1", PLATE- ID=03QQ Coordinate Source: GUIDE_STAR_CATALOG Comments: #16 IN DATA FROM 2000 TO 2003 7 REF15 CALIBRATION, RA=06H40M56.4000S +/- 1", J2000 V = 0.0 V = 12.4+/-0.1 ASTROMETRIC DEC=+09D54'7.50" +/- 1", PLATE- ID=03QQ Coordinate Source: GUIDE_STAR_CATALOG Comments: #17 IN DATA FROM 2000 TO 2003 8 REF2 CALIBRATION, RA=06H41M16.4700S +/- 1", J2000 V = 0.0 V = 12.65+/-0.1 ASTROMETRIC DEC=+09D52'13.80" +/- 1", PLATE- ID=03QQ Coordinate Source: GUIDE_STAR_CATALOG Comments: #4 IN DATA FROM 2000 TO 2003 9 REF3 CALIBRATION, RA=06H40M41.3100S +/- 1", J2000 V = 0.0 V = 13.56+/-0.1 ASTROMETRIC DEC=+09D54'14.58" +/- 1", PLATE- ID=03QQ Coordinate Source: GUIDE_STAR_CATALOG Comments: #5 IN DATA FROM 2000 TO 2003 10477( 4) - 09/07/05 18:32 - [ 4] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 10 REF4 CALIBRATION, RA=06H41M12.5400S +/- 1", J2000 V = 0.0 V = 13.74+/-0.1 ASTROMETRIC DEC=+09D52'31.91" +/- 1", PLATE- ID=03QQ Coordinate Source: GUIDE_STAR_CATALOG Comments: #6 IN DATA FROM 2000 TO 2003 11 REF6 CALIBRATION, RA=06H40M49.4900S +/- 1", J2000 V = 0.0 V = 11.38+/-0.1 ASTROMETRIC DEC=+09D53'23.42" +/- 1", PLATE- ID=03QQ Coordinate Source: GUIDE_STAR_CATALOG Comments: #8 IN DATA FROM 2000 TO 2003 10477( 4) - 09/07/05 18:32 - [ 5] Visit: 01 Visit Priority: Visit Requirements: SCHED 60%; ORIENT 280.0D TO 290.0 D; BETWEEN 05-OCT-2005:00:00:00 AND 15- OCT-2005:00:00:00 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 HD47839 FGS TRANS 1 F5ND SCANS=23,STEP-SIZE=1.0 1 488 S POS TARG 0, 0; SEQ 1-21 NON-INT ------------------------------------------------------------------------------------------------------------------------------------ 2 HD47839 FGS POS 1 F5ND 1 10 S SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 3 REF15 FGS POS 1 F583W 1 10 S SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 4 REF11 FGS POS 1 F583W 1 10 S SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 5 REF6 FGS POS 1 F583W 1 10 S SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 6 REF3 FGS POS 1 F583W 1 10 S SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 7 HD47839 FGS POS 1 F5ND 1 10 S SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 8 REF15 FGS POS 1 F583W 1 10 S SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 9 REF2 FGS POS 1 F583W 1 10 S SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 10 REF4 FGS POS 1 F583W 1 10 S SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 11 REF13 FGS POS 1 F583W 1 10 S SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 12 REF14 FGS POS 1 F583W 1 10 S SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 13 REF11 FGS POS 1 F583W 1 10 S SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 14 HD47839 FGS POS 1 F5ND 1 10 S SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 15 REF8 FGS POS 1 F583W 1 10 S SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 16 REF10 FGS POS 1 F583W 1 10 S SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 17 REF3 FGS POS 1 F583W 1 10 S SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 18 REF6 FGS POS 1 F583W 1 10 S SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 19 REF11 FGS POS 1 F583W 1 10 S SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 10477( 4) - 09/07/05 18:32 - [ 6] Exposures ----------------------------------------------------------------------------------------------------------------------------------- Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| | Requirements ----------------------------------------------------------------------------------------------------------------------------------- 20 HD47839 FGS POS 1 F5ND 1 10 S SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 21 REF15 FGS POS 1 F583W 1 10 S SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 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 | ------------------------------------------------------------------------------------------------------------------------------------ HD47839 1 FGS TRANS 1 F5ND none none none none 1 N/A HD47839 2 FGS POS 1 F5ND none none none none 1 N/A REF15 3 FGS POS 1 F583W none none none none 1 N/A REF11 4 FGS POS 1 F583W none none none none 1 N/A REF6 5 FGS POS 1 F583W none none none none 1 N/A REF3 6 FGS POS 1 F583W none none none none 1 N/A HD47839 7 FGS POS 1 F5ND none none none none 1 N/A REF15 8 FGS POS 1 F583W none none none none 1 N/A REF2 9 FGS POS 1 F583W none none none none 1 N/A REF4 10 FGS POS 1 F583W none none none none 1 N/A REF13 11 FGS POS 1 F583W none none none none 1 N/A REF14 12 FGS POS 1 F583W none none none none 1 N/A REF11 13 FGS POS 1 F583W none none none none 1 N/A HD47839 14 FGS POS 1 F5ND none none none none 1 N/A REF8 15 FGS POS 1 F583W none none none none 1 N/A REF10 16 FGS POS 1 F583W none none none none 1 N/A REF3 17 FGS POS 1 F583W none none none none 1 N/A REF6 18 FGS POS 1 F583W none none none none 1 N/A REF11 19 FGS POS 1 F583W none none none none 1 N/A HD47839 20 FGS POS 1 F5ND none none none none 1 N/A REF15 21 FGS POS 1 F583W none none none none 1 N/A 10477( 4) - 09/07/05 18:32 - [ 7] Visit: 02 Visit Priority: Visit Requirements: SCHED 60%; ORIENT 280.0D TO 290.0 D; BETWEEN 01-DEC-2005:00:00:00 AND 17- DEC-2005:00:00:00 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 HD47839 FGS TRANS 1 F5ND SCANS=23,STEP-SIZE=1.0 1 488 S POS TARG 0, 0; SEQ 1-21 NON-INT ------------------------------------------------------------------------------------------------------------------------------------ 2 HD47839 FGS POS 1 F5ND 1 10 S SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 3 REF15 FGS POS 1 F583W 1 10 S SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 4 REF11 FGS POS 1 F583W 1 10 S SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 5 REF6 FGS POS 1 F583W 1 10 S SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 6 REF3 FGS POS 1 F583W 1 10 S SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 7 HD47839 FGS POS 1 F5ND 1 10 S SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 8 REF15 FGS POS 1 F583W 1 10 S SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 9 REF2 FGS POS 1 F583W 1 10 S SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 10 REF4 FGS POS 1 F583W 1 10 S SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 11 REF13 FGS POS 1 F583W 1 10 S SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 12 REF14 FGS POS 1 F583W 1 10 S SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 13 REF11 FGS POS 1 F583W 1 10 S SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 14 HD47839 FGS POS 1 F5ND 1 10 S SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 15 REF8 FGS POS 1 F583W 1 10 S SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 16 REF10 FGS POS 1 F583W 1 10 S SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 17 REF3 FGS POS 1 F583W 1 10 S SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 18 REF6 FGS POS 1 F583W 1 10 S SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 19 REF11 FGS POS 1 F583W 1 10 S SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 10477( 4) - 09/07/05 18:32 - [ 8] Exposures ----------------------------------------------------------------------------------------------------------------------------------- Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| | Requirements ----------------------------------------------------------------------------------------------------------------------------------- 20 HD47839 FGS POS 1 F5ND 1 10 S SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 21 REF15 FGS POS 1 F583W 1 10 S SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 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 | ------------------------------------------------------------------------------------------------------------------------------------ HD47839 1 FGS TRANS 1 F5ND none none none none 1 N/A HD47839 2 FGS POS 1 F5ND none none none none 1 N/A REF15 3 FGS POS 1 F583W none none none none 1 N/A REF11 4 FGS POS 1 F583W none none none none 1 N/A REF6 5 FGS POS 1 F583W none none none none 1 N/A REF3 6 FGS POS 1 F583W none none none none 1 N/A HD47839 7 FGS POS 1 F5ND none none none none 1 N/A REF15 8 FGS POS 1 F583W none none none none 1 N/A REF2 9 FGS POS 1 F583W none none none none 1 N/A REF4 10 FGS POS 1 F583W none none none none 1 N/A REF13 11 FGS POS 1 F583W none none none none 1 N/A REF14 12 FGS POS 1 F583W none none none none 1 N/A REF11 13 FGS POS 1 F583W none none none none 1 N/A HD47839 14 FGS POS 1 F5ND none none none none 1 N/A REF8 15 FGS POS 1 F583W none none none none 1 N/A REF10 16 FGS POS 1 F583W none none none none 1 N/A REF3 17 FGS POS 1 F583W none none none none 1 N/A REF6 18 FGS POS 1 F583W none none none none 1 N/A REF11 19 FGS POS 1 F583W none none none none 1 N/A HD47839 20 FGS POS 1 F5ND none none none none 1 N/A REF15 21 FGS POS 1 F583W none none none none 1 N/A 10477( 4) - 09/07/05 18:32 - [ 9] Summary Form for Proposal 10477 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures 1 ------------------------------------------------------------------------------------------------------------------------------------ Configurations FGS ------------------------------------------------------------------------------------------------------------------------------------ Opmodes TRANS POS ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters SCANS=23 STEP-SIZE=1.0 ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements SCHED 60%; ORIENT 280.0D TO 290.0 D; BETWEEN 05-OCT-2005 00 00 00 AND 15-OCT-2005 00 00 00 POS TARG 0, 0; SEQ 1-21 NON-INT SAME POS AS 1 SCHED 60%; ORIENT 280.0D TO 290.0 D; BETWEEN 01-DEC-2005 00 00 00 AND 17-DEC-2005 00 00 00 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F5ND F583W ------------------------------------------------------------------------------------------------------------------------------------ Target Names HD47839 REF15 REF11 REF6 REF3 REF2 REF4 REF13 REF14 REF8 REF10 ------------------------------------------------------------------------------------------------------------------------------------