7502( 2) - 02/17/97 09:09 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 7502 Version: 2 Check-in Date: 17-Feb-1997 09:02:19 1.Proposal Title: DETERMINATION OF THE EXTRAGALACTIC DISTANCE SCALE. ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Cycle COSMOLOGY GO 7 ------------------------------------------------------------------------------------ 5. Investigators Contact? PI: JEREMY MOULD THE AUSTRALIAN NATIONAL UNIVERSITY CoI: Sandra Faber University of California Santa Cruz N CoI: Holland Ford Space Telescope Science Institute N CoI: Laura Ferrarese Space Telescope Science Institute N CoI: John Graham Dept of Terrestrial Magnetism, CIW N CoI: James Gunn Princeton University N CoI: Mingsheng Han University of Wisconsin N CoI: Robert Hill Goddard Space Flight Center N CoI: John Hoessel University of Wisconsin N CoI: John Huchra Harvard Smithsonian CFA N CoI: Shaun Hughes Royal Greenwich Observatory N CoI: Garth Illingworth University of California Santa Cruz N CoI: Randy Phelps Observatories of CIW N CoI: Barry Madore Caltech N CoI: Abhijit Saha Space Telescope Science Institute N CoI: Shoko Sakai JPL N CoI: Nancy Silbermann JPL N CoI: Peter Stetson Dominion Astrophysical Observatory N CoI: Brad Gibson Mount Stromlo & Siding Spring N Observatories ------------------------------------------------------------------------------------ 6. Abstract Many fundamental problems in cosmology and astrophysics remain unsettled because the value of the expansion rate is uncertain to a factor of two. The refurbished HST has provided the opportunity to break this impasse. We propose to complete a program, which in combination with other GTO and GO work should lead to a measurement of H_0 to 10\ Our main goal is the observation of Cepheids in 19 fields in 18 nearby galaxies, for the purpose of calibrating the best secondary distance indicators, including the infrared Tully-Fisher relation, the Planetary Nebula Luminosity Function, the Surface Brightness Fluctuation method, the type Ia supernovae standard candle and the type II supernova Expanding Photosphere Method. From Cycle 5 observations we have inferred H_0 = 73 +/- 10 km/sec/Mpc. In Cycle 6 we expect to obtain 10\ Fornax clusters, anchorpoints for most of the key secondary distance indicators which trace the Hubble flow to large distances. In Cycle 7 we simply need to revisit one of the Fornax galaxies in order to eliminate aliases in the periods of its longer period Cepheids. Unique features of this proposal include an end-to- end approach to the extragalactic distance scale, and a careful error budget for the Key Project. ------------------------------------------------------------------------------------ 7502( 2) - 02/17/97 09:09 - [ 2] Observations Description ------------------------ A four-orbit revisit of Cycle 6 galaxy NGC 1326A will strengthen the period determinations of longer period Cepheids. For a detailed description of the observations, see Ferrarese Etal (1996). Real Time Justification ----------------------- Time-critical observations: The revisit for NGC 1326A should occur in August or September a year after the cycle 6 visit. Special orientation: because of undersampling, the position and orientation must be kept fixed at the value adopted for the Cycle 6 observing window. We have conducted and continue with ground-based calibration and follow-up observations at Palomar, Steward, Las Campanas, La Palma and Siding Spring Observatories. Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ Data Distribution Media: 8MM Blocking Factor: 10 Ship To: STScI Ship Via: Email: ford@stsci.edu ------------------------------------------------------------------------------------ 7502( 2) - 02/17/97 09:09 - [ 3] TARGET LIST a) Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 NGC1326A GALAXY, Spiral RA = 3H 25M 04.4S +/- 2", DEC = 2000 V = 1649 SURF(V) = 24 -36D 22' 11" +/- 2" Comments: Return to Cycle 6 target 7502( 2) - 02/17/97 09:09 - [ 4] Visit: 01 Visit Requirements: BETWEEN 7-AUG-98 AND 27-SEP-98 ORIENT 274.500D to 275.500D On Hold Comments: Additional Comments: Return to the same orientation and position as cy 6 Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 NGC1326A WFPC2 IMAGE WFALL-F F555W CR-SPLIT = 0.5,CR-TOLERANCE = 0.1 1 2700 S POS TARG +10.3 , +10.3 IX END ORBIT ------------------------------------------------------------------------------------------------------------------------------------ 2 NGC1326A WFPC2 IMAGE WFALL-F F555W CR-SPLIT = 0.5,CR-TOLERANCE = 0.1 1 2700 S SAME POS AS 1 END ORBIT IX ------------------------------------------------------------------------------------------------------------------------------------ 7502( 2) - 02/17/97 09:09 - [ 5] Summary Form for Proposal 7502 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFPC2 ------------------------------------------------------------------------------------------------------------------------------------ Opmodes IMAGE ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters CR-SPLIT = 0.5 CR-TOLERANCE = 0.1 ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category COSMOLOGY ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements BETWEEN 7-AUG-98 AND 27-SEP-98 ORIENT 274.500D to 275.500D POS TARG +10.3 , +10.3 END ORBIT SAME POS AS 1 END ORBIT ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F555W ------------------------------------------------------------------------------------------------------------------------------------ Target Names NGC1326A ------------------------------------------------------------------------------------------------------------------------------------