NASA Hubble Space Telescope Daily Report # 3436
HUBBLE SPACE TELESCOPE
DAILY REPORT # 3436
PERIOD COVERED: DOY 239
OBSERVATIONS SCHEDULED
ACS 9675
CCD Daily Monitor
This program consists of basic tests to monitor, the read noise, the
development of hot pixels and test for any source of noise in ACS CCD
detectors. This programme will be executed once a day for the entire
lifetime of ACS.
ACS 9984
Cosmic Shear With ACS Pure Parallels
Small distortions in the shapes of background galaxies by foreground
mass provide a powerful method of directly measuring the amount and
distribution of dark matter. Several groups have recently detected
this weak lensing by large-scale structure, also called cosmic shear.
The high resolution and sensitivity of HST/ACS provide a unique
opportunity to measure cosmic shear accurately on small scales. Using
260 parallel orbits in Sloan textiti {F775W} we will measure for the
first time: beginlistosetlength sep0cm setlengthemsep0cm setlength
opsep0cm em the cosmic shear variance on scales <0.7 arcmin, em the
skewness of the shear distribution, and em the magnification effect.
endlist Our measurements will determine the amplitude of the mass
power spectrum sigma_8Omega_m^0.5, with signal-to-noise {s/n} ~ 20,
and the mass density Omega_m with s/n=4. They will be done at small
angular scales where non-linear effects dominate the power spectrum,
providing a test of the gravitational instability paradigm for
structure formation. Measurements on these scales are not possible
from the ground, because of the systematic effects induced by PSF
smearing from seeing. Having many independent lines of sight reduces
the uncertainty due to cosmic variance, making parallel observations
ideal.
ACS/HRC 9823
Rings of Uranus: Dynamics, Particle Properties and Shepherding Moons
We propose to image the rings and small inner satellites of Uranus
using the High Resolution Channel of the ACS. The revolutionary
capabilities of the ACS will allow us to address a variety of
important questions relating to ring properties and ring-moon
interactions. Observations at a range of wavelengths and phase angles
will reveal the opposition surges of these rings and moons, providing
information on color and surface structure. Measurements of the ring
in front of the planet will provide complementary information on
optical depth; any variations of optical depth with wavelength will
reveal the rings’ poorly-constrained population of embedded dust. The
rings of Uranus are closing rapidly as the planet approaches equinox
in 2007, an event that takes place only every 42 years. Using this
opportunity, our observations will be repeated at different solar and
terrestrial tilt angles; this sequence of images will be particularly
valuable for constraining the physical thickness and packing density
of the rings. We will place particular emphasis on the rotational
variations of the Epsilon Ring, whose radial width {and therefore its
packing density} varies by a factor of five. In addition, a set of
deep exposures targeted just off the planet will enable us to detect
any 4-5 km moons embedded within the ring system. Dynamicists invoke
numerous such moons to "shepherd" the many sharp ring boundaries, so
this will serve as a definitive test of the theory.
ACS/WFC 9891
A snapshot survey of rich stellar clusters in the Large and Small
Magellanic Clouds
Rich stellar clusters are vital to a wide variety of astrophysical
research, from stellar evolution studies to the formation and
evolution of galaxies. In this context, it is important to understand
how rich star clusters form and evolve. The cluster systems in the LMC
and SMC are particularly important in achieving this, because they are
the only systems which contain clusters at all stages of evolution
while being close enough to be studied as fully resolved stellar
populations – although in general this requires the capabilities of
HST. We have recently investigated the structural evolution of LMC and
SMC clusters using archival WFPC2 data, and demonstrated a dramatic
trend in the sizes of these clusters with age. We have shown that this
trend likely represents genuine structural evolution in these
clusters, although it is not clear whether we are observing a
dynamical process or the signature of changing formation conditions.
This result has implications for all astronomical research involving
massive stellar clusters. To develop this work further requires the
extension of our two samples, so that they are statistically
quantifiable. This will allow a number of key questions regarding the
structural evolution trend to be answered. We propose a two-colour
ACS/WFC SNAP survey of rich Magellanic Cloud clusters to achieve this
aim. The unique resolution and sensitivity of ACS/WFC is required for
success, because of the crowded nature of the targets. The SNAP data
will have a large number of additional applications, both to globular
cluster and Magellanic Cloud research.
ACS/WFPC2 9488
Cosmic Shear – with ACS Pure Parallel Observations
The ACS, with greater sensitivity and sky coverage, will extend our
ability to measure the weak gravitational lensing of galaxy images
caused by the large scale distribution of dark matter. We propose to
use the ACS in pure parallel {non- proprietary} mode, following the
guidelines of the ACS Default Pure Parallel Program. Using the HST
Medium Deep Survey WFPC2 database we have measured cosmic shear at
arc-min angular scales. The MDS image parameters, in particular the
galaxy orientations and axis ratios, are such that any residual
corrections due to errors in the PSF or jitter are much smaller than
the measured signal. This situation is in stark contrast with
ground-based observations. We have also developed a statistical
analysis procedure to derive unbiased estimates of cosmic shear from a
large number of fields, each of which has a very small number of
galaxies. We have therefore set the stage for measurements with the
ACS at fainter apparent magnitudes and smaller, 10 arc-second scales
corresponding to larger cosmological distances. We will adapt existing
MDS WFPC2 maximum likelihood galaxy image analysis algorithms to work
with the ACS. The analysis would also yield an online database similar
to that in archive.stsci.edu/mds/
FGS 9969
FGS Astrometry of the Extrasolar Planet of Epsilon Eridani
We propose observations with HST/FGS in Position Mode to determine the
astrometric elements {perturbation orbit semimajor axis and
inclination} of the candidate extra-solar planet around the K2 V star
Epsilon Eridani that has been detected by Doppler spectroscopy. These
observations will also permit us to determine the actual mass of the
planet by providing the sin{i} factor which can not be determined with
the radial velocity method. High precision radial velocity {RV}
measurements spanning the years 1980.8–2000.0 for the nearby {3.22
pc} star Epsilon Eri show convincing variations with a period of ~ 7
yrs. These data represent a combination of six independent data sets
taken with four different telescopes. A least squares orbital solution
using robust estimation yields orbital parameters of period, P = 6.9
yrs, velocity K- amplitude = 19 m/s, eccentricity e = 0.6, projected
companion mass M_B sin{i} = 0.83 M_Jupiter. An estimate of the
inclination yields a perturbation semi-major axis, Alpha = 0arcs0022,
easily within the reach of HST/FGS astrometry.
NIC1/NIC2/STIS/CCD/WFPC2 9738
Spectroscopy and Polarimetry of Mars at Closest Approach
We plan a coordinated program of spectroscopy, imaging, and
spectropolarimetry of Mars during the August 2003 opposition to study
the composition and physical state of surface materials and airborne
aerosols. The observations include {a} Moderate spectral resolution
290 to 570 nm STIS long-slit push-broom imaging spectroscopy of Mars,
to constrain the properties of airborne aerosol particles and to
search for and globally map iron-bearing minerals that are diagnostic
of specific past climatic conditions; {b} WFPC2 UV-VIS images designed
primarily to quantify the effects of ice and dust aerosols on our STIS
spectra; {c} NICMOS near-IR images to search for and globally map the
presence of hydrated surface minerals; and {d} ACS multispectral
polarizer images to provide critical phase function measurements
needed to constrain the physical properties of the Martian surface
layer. The observations are timed to take advantage of the closest
approach of Mars to Earth for the next several hundred years. Images
and spectra will be acquired at a spatial scale comparable to existing
spacecraft orbital spectroscopy data {~10 km/pixel} and in wavelength
regions not sampled by past or current Mars spacecraft
instrumentation. These observations also provide complementary
scientific and calibration measurements in support of current and
future NASA and ESA Mars exploration missions.
NICMOS 8791
NICMOS Post-SAA calibration – CR Persistence Part 2
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.
STIS 9606
CCD Dark Monitor-Part 2
Monitor the darks for the STIS CCD.
STIS 9608
CCD Bias Monitor – Part 2
Monitor the bias in the 1×1, 1×2, 2×1, and 2×2 bin settings at gain=1,
and 1×1 at gain = 4, to build up high-S/N superbiases and track the
evolution of hot columns.
STIS 9633
STIS parallel archive proposal – Nearby Galaxies – Imaging and
Spectroscopy
Using parallel opportunities with STIS which were not allocated by the
TAC, we propose to obtain deep STIS imagery with both the Clear
{50CCD} and Long-Pass {F28X50LP} filters in order to make
color-magnitude diagrams and luminosity functions for nearby galaxies.
For local group galaxies, we also include G750L slitless spectroscopy
to search for e.g., Carbon stars, late M giants and S-type stars. This
survey will be useful to study the star formation histories, chemical
evolution, and distances to these galaxies. These data will be placed
immediately into the Hubble Data Archive.
STIS/CCD 10000
STIS Pure Parallel Imaging Program: Cycle 12
This is the default archival pure parallel program for STIS during
cycle 12.
STIS/CCD 9839
Recombination Lines and Temperature Structure in Planetary Nebulae
A high-spatial resolution study of recombination lines {RLs} in bright
compact planetary nebulae {PNs} is proposed. Many PNs show a large
discrepancy between abundances derived from O II RLs and those derived
from [O III]. Others show little or no discrepancy. The PNs with small
discrepancies are more compact and high surface brightness. This
program seeks to understand why PNs show such differences by studying
the RLs at high spatial resolution in the compact PNs NGC 6572 and NGC
6790, which show no discrepancy between O II and [O III], to compare
with ground-based studies of the larger PNs NGC 6153 and NGC 6720. The
goal is to determine if the distribution of RL emission in NGC 6572
and NGC 6790 is more consistent with radiative recombination than in
NGC 6720, where the RL emission is more centrally peaked than [O III].
This will allow us to demonstrate whether or not it is the RLs that
are preferentially enhanced in the nebulae with large discrepancies.
The Cat’s Eye nebula NGC 6543 will also be observed, to determine if
the enhanced RL emission is connected to the presence of X-ray
emitting gas, as might be expected if the enhanced RLs are a result of
high temperature dielectronic recombination.
STIS/MA2 9804
Experimental Proof of the Neutrino Process in SN from Boron Isotope
Measurements
The light elements Li, Be, and B are formed in the Big Bang {Li} and
by Cosmic Ray {CR} spallation. But the abundance of 11B has never been
satisfactorily explained: 11B/10B in the solar system is 4.0, CR
spallation predicts 2.5. There needs to be another source of 11B.
Woosely et al. {1990} predict the large flux of neutrinos in Type II
supernovae will sythesize elements, including converting 12C to 11B.
This "neutrino process" has never been experimentally verified. A
"smoking gun" would be to find a metal poor star whose elements came
primarily from Type II SN and whose B is pure 11B — only the neutrino
process could produce that. In a previous cycle we obtained STIS
measurements of a metal poor star and were able to clearly show that
11B/10B <= 4. We now ask for additional observations of higher S/N,
which can distinguish if 11B/10B = 4, or if the mix is pure 11B. In
either case we will end up with a precise measure of how much 11B in
old stars is NOT produced by CRs, and likely due to SN, and can place
a new constraint on the temperature and density of SN models in the
region where neutrino-induced nucleosynthesis is thought to take
place. Although this test could be made in a single star, we ask to
observe two, to increase the confidence in what is a subtle isotopic
measurement. We propose to observe the brightest two suitable metal
poor stars. One is in the CVZ.
WFPC2 10065
Mars at Closest Approach
We will take highest-quality HST images of Mars at it’s closest
approach in ca 50,000 years.
WFPC2 9595
WFPC2 CYCLE 11 SUPPLEMENTAL DARKS pt3/3
This dark calibration program obtains 3 dark frames every day to
provide data for monitoring and characterizing the evolution of hot
pixels.
WFPC2 9709
POMS Test Proposal: WFII parallel archive proposal
This is the generic target version of the WFPC2 Archival Pure Parallel
program. The program will be used to take parallel images of random
areas of the sky, following the recommendations of the 2002 Parallels
Working Group.
WFPC2 9964
Dynamical Masses of White Dwarfs from Resolved Sirius-Like Binaries
In Cycle 8 we initiated a WFPC2 snapshot survey for resolved,
“Sirius-like” systems containing hot white-dwarf companions of
cooler main-sequence stars. Out of 17 systems observed to date, 8 have
been resolved with WFPC2 by using UV filters. Two of the resolved
systems—56 Persei and Zeta Cygni—have predicted or known orbital
periods short enough that dynamical masses can be determined for the
white dwarfs within reasonable times. These would thus add to the
extremely small number of white dwarfs presently having accurately and
directly measured masses. We propose to image them annually in the UV
with WFPC2. In addition, we will observe Zeta Cyg with FGS in order to
measure the absolute motion of the optical component, needed for the
mass solution. We also propose to observe Sirius itself with WFPC2
over the next 3 Cycles. The resulting astrometric data will not only
greatly improve the precision of the binary orbit and the dynamical
mass measurements for both the main-sequence and white-dwarf
components, but will also test definitively for the claimed presence
of a third body in this famous system.
WFPC2/ACS/WFC 9720
Age-dating Star Clusters in M101
M101 represents perhaps our best chance to study the stellar
population of a luminous, late type spiral galaxy, due to both its
proximity and its face-on orientation. For these reasons, 13 orbits of
HST ACS observing time were allocated in Cycle 11 to obtain a 4×4
mosaic image of M101 in BVI . Unfortunately, a degeneracy between age
and reddening exists when only these three bands are available. Hence,
we propose to augment these observations by obtaining WFPC2 U band and
ACS H alpha images. This will enable the accurate determination of
ages for the young clusters, secure identifications of 75-100 old
globular clusters, and allow a quantitative study of the HII region
sizes and structures. Some of the specific questions we will address
are: How do the young clusters form and evolve? What fraction of the
clusters dissolve and on what timescales? Do clusters evolve with a
continuum of properties? Using WFPC2 and ACS in parallel, and making
use of the fact that M101 is in the CVZ, allows us to greatly enhance
the science return of previous HST observations for the cost of only 4
orbits.
FLIGHT OPERATIONS SUMMARY:
Significant Spacecraft Anomalies: (The following are preliminary
reports of potential non-nominal performance that will be
investigated.)
HSTAR 9129: FHST Full Maneuver (U1,3FM) Updates @ 239/09:29:59Z and
09:32:44Z using FHST 2 an failed with Error Box
indicating mnemonics QEBSTFG0, QEBSTFG1, and
QEBSTFG2. Subsequent GS A 239/09:35:29Z with
Primary FGS Search Radius = 55 successful. Under
investigation.
COMPLETED OPS REQs: NONE
OPS NOTES EXECUTED: NONE
SCHEDULED SUCCESSFUL FAILURE TIMES FGS GSacq 11 11 FGS REacq 05 05 FHST Update 21 19 239/0930z (HSTAR 9129) LOSS of LOCK
SIGNIFICANT EVENTS:
HST Command Timing test scheduled 240/11:00Z – 20:00Z with GDOC, SOC,
HITT, and CCS using CCS "C" String with Release 4.0.3 and PRD D06300
and CCS "D" String with Release 5.0.3 and PRD D06300S. The purpose of
this testing is to run comparison testing with CCS Release 5.0.3 on
the "D" String and CCS Release 4.0.3 on the "C" String.
HST Checkout of HSTUPS to ANCC scheduled 240/13:00Z – 15:00Z with WSC
TC, GDOC, HITT, STScI, PSS DEV, System Administrators. The purpose of
this testing is to verify the functionality of the new HSTUPS Software
Release 14.