9233( 4) - 10/01/01 13:29 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 9233 Version: 4 Check-in Date: 01-Oct-2001 13:28:23 1.Proposal Title: FGS Astrometry of the Extrasolar Planet of GL876 ------------------------------------------------------------------------------------ 2. Proposal For 3. Cycle GO 10 ------------------------------------------------------------------------------------ 4. Investigators Contact? PI: Thierry Forveille Observatoire de Grenoble CoI: Dr. G. Fritz Benedict McDonald Observatory N CoI: Dr. Paul Butler Anglo-Australian Observatory N CoI: Dr. Xavier Delfosse Observatorie de Geneve N CoI: Dr. William Jefferys University of Texas N CoI: Dr. Geoffrey W. Marcy Sna Francisco State University N CoI: Prof Michel Mayor Observatorie de Geneve N CoI: Ms. Barbara McArthur McDonald Observatory N CoI: Dr. Edmund Nelan STScI Y CoI: Dr. Christian Perrier Observatorie de Genoble N ------------------------------------------------------------------------------------ 5. Abstract We propose to continue our astrometric observations of GL876 with HST/FGS in Position Mode to confirm the radial velocity detection of an extra-solar planet around the M4 dwarf star. Our objective is to determine the actual mass of the planet without the unknown 1/sini factor of the radial velocity methods. This will be the first extra-solar planet whose mass is actually determined from first principles. In this continuation proposal we observe GL876 and its field of reference stars to determine the star's parallax and proper motion which must be determined to allow us to isolate the star's reflex motion due to its orbit about the system's common center of mass. ------------------------------------------------------------------------------------ 9233( 4) - 10/01/01 13:29 - [ 2] Observations Description ------------------------ We observe the target GL876 and 6 astrometric reference stars within the FGS in one orbit of HST time on two ocassions near the Novemeber epoch of maximum parallax factor to accurately determine the parallax and proper motion of GL876 relative to its reference frame. In the cycle 8 and 9 proposals of the program we observed GL876 with sufficient sampling at the May epoch of maximum parallax factor, but we have only one epoch of FGS3 data for the November time of maximum parallax factor. Therefore, to improve our parallax determination, we will utilize our two HST orbits in this proposal to observe GL876 in November 2001. The orbits will be scheduled to occur near the time of maximum parallax factor and at the same star/planet orbital phase as in the past May and Novemnber visits. Each orbit of HST observing will be filled with multiple measurements of Gl876 and its reference stars by the FGS in Position mode. Once the parallax and proper motion are determined, we anticipate the overall accuracy of our 24 measurements obtained in cycle 8 to approach 0.15mas. With a major axis of 0.55/sin(i) mas for GL876's reflex motion, 0.15 mas represents a 4-sigma detection for the worst case of an edge-on orbit. Real Time Justification ----------------------- The timming of the observations is critical in order to observe the target at times of maximum elongation and near maximum parallax factor. Calibration Justification ------------------------- Additional Comments ------------------- These observations (using FGS3) to determine the parallax and proper motion of GL876 must occur at times of maximum parallax factor (May and November), and at ORIENTS specified in the exposure lines. We continue to use FGS3 because FGS1r is not yet calibrated in POS mode, and because our cycle 8 observations were made with FGS3, and finally, FGS3 had demonstrated remarkable stability of its POS mode calibrations. ------------------------------------------------------------------------------------ 9233( 4) - 10/01/01 13:29 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 GL876 STAR, CALIBRATION, RA=22H 53M 16.73S +/- 1", DEC=- J2000 V = 11.36 ASTROMETRIC 14D 15' 49.3" +/- 1" Coordinate Source: GUIDE_STAR_CATALOG Comments: M4 Dwarf star with massive planet. GSC_ID = 5819.00951 2 GL876-2-REF STAR, CALIBRATION, RA=22H 53M 10.6S +/- 1", DEC=- J2000 V = 15.0+/-0.5 ASTROMETRIC 14D 15' 50.5" +/- 1" Coordinate Source: GUIDE_STAR_CATALOG Comments: GSC ID 5819.00951. 3 GL876-3-REF STAR, CALIBRATION, RA=22H 52M 58.6S +/- 1", DEC=- J2000 V = 14.4+/-0.5 ASTROMETRIC 14D 17' 24.8" +/- 1" Coordinate Source: GUIDE_STAR_CATALOG Comments: GSC ID = 5819.01049. GSC mag V = 14.37 4 GL876-4-REF STAR, CALIBRATION, RA=22H 52M 57.8S +/- 1", DEC=- J2000 V = 15.0+/-0.5 ASTROMETRIC 14D 19' 43.6" +/- 1" Coordinate Source: GUIDE_STAR_CATALOG Comments: GSC ID 5819.010496. GSC mag V=11.59. Star is a binary. Fainter magnitude specification allows for POS mode acquisition. 5 GL876-5-REF STAR, CALIBRATION, RA=22H 53M 44.225S +/- 1", DEC=- J2000 V = 14.4+/-0.3 ASTROMETRIC 14D 14' 19.356" +/- 1" Coordinate Source: GUIDE_STAR_CATALOG Comments: GSC ID 5819.00979. GSC mag V = 14.1 6 GL876-6-REF STAR, CALIBRATION, RA=22H 53M 39.38S +/- 1", DEC=- J2000 V = 15.5+/-0.5 ASTROMETRIC 14D 15' 39.780" +/- 1" Coordinate Source: OTHER_SOURCE Comments: This star is from the USNO A2.0 catalogue. It is not in the GSC. 7 GL876-7-REF STAR, CALIBRATION, RA=22H 53M 56.60S +/- 1", DEC=- J2000 V = 14.2+/-0.5 ASTROMETRIC 14D 16' 12.540" +/- 1" Coordinate Source: GUIDE_STAR_CATALOG Comments: GSC_ID = 5819.00940 8 GL876-8-REF STAR, CALIBRATION, RA=22H 54M .672S +/- 1", DEC=- J2000 V = 15.46 ASTROMETRIC 14D 15' 34.740" +/- 1" Coordinate Source: GUIDE_STAR_CATALOG Comments: GSC_ID = 5819.00987 9233( 4) - 10/01/01 13:29 - [ 4] Visit: 01 Visit Priority: Visit Requirements: ORIENT 63.0D TO 70.0D SCHED 40% BETWEEN 15-Nov-2001 AND 17-Nov-2001 On Hold Comments: Additional Comments: This visit is critically timed for determination of the object's parallax and proper motion at constant orbital phase of companion. Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 10 GL876 FGS POS 3 F583W 1 15 S SEQ 10-160 NON-INT POS TARG -75.0,-80.0 GS ACQ SCENARIO SINGLE ------------------------------------------------------------------------------------------------------------------------------------ 20 GL876-5-REF FGS POS 3 F583W 1 30 S SAME POS AS 10 ------------------------------------------------------------------------------------------------------------------------------------ 30 GL876-2-REF FGS POS 3 F583W 1 35 S SAME POS AS 10 ------------------------------------------------------------------------------------------------------------------------------------ 40 GL876-3-REF FGS POS 3 F583W 1 30 S SAME POS AS 10 ------------------------------------------------------------------------------------------------------------------------------------ 50 GL876 FGS POS 3 F583W 1 20 S SAME POS AS 10 ------------------------------------------------------------------------------------------------------------------------------------ 60 GL876-5-REF FGS POS 3 F583W 1 30 S SAME POS AS 10 ------------------------------------------------------------------------------------------------------------------------------------ 70 GL876-6-REF FGS POS 3 F583W 1 30 S SAME POS AS 10 ------------------------------------------------------------------------------------------------------------------------------------ 80 GL876 FGS POS 3 F583W 1 20 S SAME POS AS 10 ------------------------------------------------------------------------------------------------------------------------------------ 90 GL876-2-REF FGS POS 3 F583W 1 35 S SAME POS AS 10 ------------------------------------------------------------------------------------------------------------------------------------ 100 GL876-3-REF FGS POS 3 F583W 1 30 S SAME POS AS 10 ------------------------------------------------------------------------------------------------------------------------------------ 110 GL876 FGS POS 3 F583W 1 20 S SAME POS AS 10 ------------------------------------------------------------------------------------------------------------------------------------ 120 GL876-5-REF FGS POS 3 F583W 1 30 S SAME POS AS 10 ------------------------------------------------------------------------------------------------------------------------------------ 130 GL876-6-REF FGS POS 3 F583W 1 30 S SAME POS AS 10 ------------------------------------------------------------------------------------------------------------------------------------ 140 GL876-2-REF FGS POS 3 F583W 1 35 S SAME POS AS 10 ------------------------------------------------------------------------------------------------------------------------------------ 150 GL876 FGS POS 3 F583W 1 20 S SAME POS AS 10 ------------------------------------------------------------------------------------------------------------------------------------ 160 GL876-3-REF FGS POS 3 F583W 1 30 S SAME POS AS 10 ------------------------------------------------------------------------------------------------------------------------------------ 9233( 4) - 10/01/01 13:29 - [ 5] Visit: 02 Visit Priority: Visit Requirements: ORIENT 64.0D TO 70.0D SCHED 40% BETWEEN 27-Nov-2001 AND 03-Dec-2001 On Hold Comments: Additional Comments: This visit is critically timed for determination of the object's parallax and proper motion at constant orbital phase of companion. Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 10 GL876 FGS POS 3 F583W 1 15 S SEQ 10-160 NON-INT POS TARG -75.0,-80.0 GS ACQ SCENARIO SINGLE ------------------------------------------------------------------------------------------------------------------------------------ 20 GL876-5-REF FGS POS 3 F583W 1 30 S SAME POS AS 10 ------------------------------------------------------------------------------------------------------------------------------------ 30 GL876-2-REF FGS POS 3 F583W 1 35 S SAME POS AS 10 ------------------------------------------------------------------------------------------------------------------------------------ 40 GL876-3-REF FGS POS 3 F583W 1 30 S SAME POS AS 10 ------------------------------------------------------------------------------------------------------------------------------------ 50 GL876 FGS POS 3 F583W 1 20 S SAME POS AS 10 ------------------------------------------------------------------------------------------------------------------------------------ 60 GL876-5-REF FGS POS 3 F583W 1 30 S SAME POS AS 10 ------------------------------------------------------------------------------------------------------------------------------------ 70 GL876-6-REF FGS POS 3 F583W 1 30 S SAME POS AS 10 ------------------------------------------------------------------------------------------------------------------------------------ 80 GL876 FGS POS 3 F583W 1 20 S SAME POS AS 10 ------------------------------------------------------------------------------------------------------------------------------------ 90 GL876-2-REF FGS POS 3 F583W 1 35 S SAME POS AS 10 ------------------------------------------------------------------------------------------------------------------------------------ 100 GL876-3-REF FGS POS 3 F583W 1 30 S SAME POS AS 10 ------------------------------------------------------------------------------------------------------------------------------------ 110 GL876 FGS POS 3 F583W 1 20 S SAME POS AS 10 ------------------------------------------------------------------------------------------------------------------------------------ 120 GL876-5-REF FGS POS 3 F583W 1 30 S SAME POS AS 10 ------------------------------------------------------------------------------------------------------------------------------------ 130 GL876-6-REF FGS POS 3 F583W 1 30 S SAME POS AS 10 ------------------------------------------------------------------------------------------------------------------------------------ 140 GL876-2-REF FGS POS 3 F583W 1 35 S SAME POS AS 10 ------------------------------------------------------------------------------------------------------------------------------------ 150 GL876 FGS POS 3 F583W 1 20 S SAME POS AS 10 ------------------------------------------------------------------------------------------------------------------------------------ 160 GL876-3-REF FGS POS 3 F583W 1 30 S SAME POS AS 10 ------------------------------------------------------------------------------------------------------------------------------------ 9233( 4) - 10/01/01 13:29 - [ 6] Summary Form for Proposal 9233 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures 3 ------------------------------------------------------------------------------------------------------------------------------------ Configurations FGS ------------------------------------------------------------------------------------------------------------------------------------ Opmodes POS ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ORIENT 63.0D TO 70.0D SCHED 40% BETWEEN 15-Nov-2001 AND 17-Nov-2001 SEQ 10-160 NON-INT POS TARG -75.0,-80.0 GS ACQ SCENARIO SINGLE SAME POS AS 10 ORIENT 64.0D TO 70.0D SCHED 40% BETWEEN 27-Nov-2001 AND 03-Dec-2001 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F583W ------------------------------------------------------------------------------------------------------------------------------------ Target Names GL876 GL876-5-REF GL876-2-REF GL876-3-REF GL876-6-REF ------------------------------------------------------------------------------------------------------------------------------------