#1
|
|||
|
|||
DAILY REPORT #3911
HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science
DAILY REPORT #3911 PERIOD COVERED: UT July 27, 2005 (DOY 208) OBSERVATIONS SCHEDULED ACS/HRC 10435 Merger-Induced Populations in Early-Type Galaxy Cores Hierarchical formation models predict that early-type galaxies are built up over an extended period from mergers of smaller systems, a process which should leave long- lived signatures in their light profiles and stellar population colors. Merger events should have continued up to relatively recent times {the last 1-5 Gyr}, and many ellipticals and S0 bulges should therefore show evidence of multiple, discrete, intermediate-age populations. Although there is substantial observational support for a dissipational merger origin for some early-type galaxies, most do not exhibit the expected anomalies in either their light profiles or color distributions. However, existing searches {mainly in the V and I bands} have not probed very deeply. Here we propose high resolution, broad-band, near-ultraviolet {2500-3400 A} imaging of the cores of bright early-type galaxies. This is the most sensitive probe available for the detection of spatially-segregated, multiple population components with ages in the range 1-5 Gyr. Our sample consists of dust- and AGN-free systems with both normal and mildly anomalous central light profiles. There is very little existing information on the near-UV structure of early-type galaxies, and our program would effectively explore new terrain. ACS/HRC/WFC 10389 ACS CCDs daily monitor - Cycle 13 - Part 2 This program consists of a set of basic tests to monitor, the read noise, the development of hot pixels and test for any source of noise in ACS CCD detectors. The files, biases and dark will be used to create reference files for science calibration. This program will be for the entire lifetime of ACS. ACS/HRC/WFC 10400 Unravelling NGC 3125-1: The Most Extreme Wolf-Rayet Star Cluster Known in the Local Universe Based on cycle 10 STIS UV spectroscopy, we have recently discovered a star cluster, NGC 3125-1, which has the strongest known He II 1640 emission {of stellar origin} in the local universe. The number of implied WR stars is more than an order of magnitude higher than for any other well-studied giant HII region. Because strong He II 1640 emission has been discovered in the composite spectra of redshift 3 Lyman Break Galaxies, NGC 3125-1 potentially provides a unique opportunity to study a nearby object with direct implications for the stellar populations observed in the early universe. In order to understand the origin of this anomalously strong WR feature, we propose to obtain the first high resolution imaging of NGC 3125-1, at wavelengths from the far ultraviolet through the near infrared. This will allow us to simultaneously place it in the context of more familiar objects, such as R136 in 30 Doradus, while also unravelling the physics responsible for the observed UV spectral signature. ACS/HRC/WFC/WFPC2 10384 Focus Monitor The focus of HST is measured from WFPC2/PC and ACS/HRC images of stars. Multiple exposures are taken in parallel over an orbit to determine the influence of breathing on the derived mean focus. Observations are taken of clusters with suitable orientations to ensure stars appear in all fields. ACS/WFC/WFPC2 10499 Life Before the Fall: Morphological Evolution of Galaxies in Groups Prior to Cluster Assembly at z=0.37 We propose to obtain a deep ACS/WFC mosaic of a protocluster comprised of 4 distinct galaxy groups that are gravitationally bound to each other at z=0.37. The galaxy groups have a total combined mass comparable to the Coma cluster and already have twice as many absorption line galaxies as the field. The SG1120 complex thus provides an unprecedented opportunity for determining whether "pre-processing" in the group environment is responsible for the bulk of observed diffences between galaxies in nearby clusters and those in the field. High resolution imaging with HST is needed to morphologically classify the group members and measure their structural parameters. By combining the early-type fraction and morphology-density relation in SG1120 with results from our wide-field spectroscopic survey, we will test whether spectral and morphological transformation timescales are decoupled on group scales and isolate the environmental mechanisms responsible for such evolution. We will also measure the Fundamental Plane and M/L ratios of the early-type members to constrain their formation epoch and how their stellar populations have evolved. Observations of the multiple galaxy groups in SG1120 provide a unique dataset to the community and will aid our understanding of how galaxies evolve in the still poorly studied group regime. NIC1/NIC2/NIC3 8793 NICMOS Post-SAA calibration - CR Persistence Part 4 A new procedure proposed to alleviate the CR-persistence problem of NICMOS. Dark frames will be obtained immediately upon exiting the SAA contour 23, and every time a NICMOS exposure is scheduled within 50 minutes of coming out of the SAA. The darks will be obtained in parallel in all three NICMOS Cameras. The POST-SAA darks will be non-standard reference files available to users with a USEAFTER date/time mark. The keyword 'USEAFTER=date/time' will also be added to the header of each POST-SAA DARK frame. The keyword must be populated with the time, in addition to the date, because HST crosses the SAA ~8 times per day so each POST-SAA DARK will need to have the appropriate time specified, for users to identify the ones they need. Both the raw and processed images will be archived as POST-SAA DARKSs. Generally we expect that all NICMOS science/calibration observations started within 50 minutes of leaving an SAA will need such maps to remove the CR persistence from the science images. Each observation will need its own CRMAP, as different SAA passages leave different imprints on the NICMOS detectors. NIC2 10428 The colours of QSO host galaxies at z=2 and the evolution of their stellar masses We propose to use NICMOS imaging to measure the rest-frame optical/UV colours of a complete sample of 10 QSO host galaxies at redshifts between z=1.5 and z=2. From our cycle 11 HST observations {the GEMS project} we know that QSO host galaxies at redshifts of z~1 show blue colors despite having early-type morphologies. This is in excellent agreement with recent SDSS results on low-z AGN hosts, suggesting that QSO- type activity in galaxies correlates strongly with the presence of a young stellar population. Our proposed NICMOS observations will allow us to test the validity of this hypothesis out to z~2, by relating the observed QSO host colours to those of normal galaxies at similar redshifts taken from GOODS. We have already established within GEMS that the QSO hosts in our sample possess substantial UV luminosities, most likely originating from young stars. Knowing rest-frame colors, we can estimate stellar ages and stellar masses. For the first time will it be possible to determine the evolution of stellar masses in QSO host galaxies from z=2, the epoch of maximum QSO activity, to the present. Our results will shed light on the relation between nuclear activity and the star formation history of galaxies, and how these processes may jointly drive the cosmic evolution of QSOs and galaxies. FLIGHT OPERATIONS SUMMARY: Significant Spacecraft Anomalies: (The following are preliminary reports of potential non-nominal performance that will be investigated.) HSTARS: (None) COMPLETED OPS REQUEST: #17482-1: FSW 2.8A EEPROM Installation @ 208/1457z COMPLETED OPS NOTES: (None) SCHEDULED SUCCESSFUL FGS Gsacq 04 04 FGS Reacq 10 10 FHST Update 08 08 SIGNIFICANT EVENTS: FSW 2.8 Release A was successfully installed in HST486 EEPROM at 208/14:54:53z. The 2.8A EEPROM load was completed at 208/13:34:26z. The baseline EEPROM memory dump was completed at 208/14:47:29z and verified by FSW. |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
NASA PDF - Apollo Experience Reports - 114 reports | Rusty | History | 1 | July 27th 05 03:52 AM |
Ed Conrad's NEW Letter to Prof. Michael Behe | Ed Conrad | Astronomy Misc | 0 | June 21st 05 10:50 AM |
NASA Voyager PDF's 1963 - 1967 | Rusty | History | 1 | April 1st 05 12:05 AM |
NASA PDF Mercury, Gemini, Apollo reports free online | Rusty Barton | History | 81 | October 3rd 04 05:33 PM |
DEATH DOES NOT EXIST -- Coal Mine Rescue Proves It | Ed Conrad | Space Shuttle | 4 | August 2nd 03 01:00 AM |