Daily # 4249

HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science

DAILY REPORT # 4249

PERIOD COVERED: UT November 29, 2006 (DOY 333)

OBSERVATIONS SCHEDULED

ACS/HRC/WFC 10758

ACS CCDs daily monitor

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 programme will be
for the entire lifetime of ACS. Changes from cycle 13:- The default
gain for WFC is 2 e-/DN. As before bias frames will be collected for
both gain 1 and gain 2. Dark frames are acquired using the default
gain {2}. This program cover the period May, 31 2006- Oct, 1-2006. The
first half of the program has a different proposal number: 10729.

ACS/SBC 10578

Eclipsing Binaries in the Local Group: Calibration of the Zero-point
of the Cosmic Distance Scale and

The Andromeda Galaxy {M31} is potentially a crucial calibrator for the
Cosmic Distance Scale, and thus for determining the age and evolution
of the Universe. Yet currently the M31 distance modulus {~750 kpc} is
is still uncertain to within 0.1-0.15 mag. We have demonstrated in our
work on the LMC distance that double-lined eclipsing binaries can
serve as excellent "standard candles''. Distances derived from
eclipsing binaries are basically geometric and essentially free from
many assumptions and uncertainties that plague other less direct
methods, such as metallicity differences and calibration zeropoints.
The absolute radii of the component stars of eclipsing binaries can be
determined to better than a few percent from the time-tested analyses
of their light and radial velocity curves. With accurate radii and
temperatures, it is possible to determine reliable distances. We are
extending our program of using eclipsing binaries as standard candles
to determine an accurate distance to M31. As a first step, we are
proposing to carry out HST spectroscopy of two carefully selected 19th
mag early-B eclipsing binaries in M31. HST/ACS prism/grism
low-resolution spectrophotometry {115-900 nm} is only missing key
element of this program and is used to determine reliable values for
T_eff, [Fe/H], and ISM extinction. These quantities, when combined
with the results from our existing light and radial velocity curves
for the two targets, will yield the stellar masses, radii,
luminosities, and, importantly, the distances. The resulting
fundamental stellar properties will be the first determined for stars
in M31. Based on our previous experience, we expect to reduce the
uncertainty of the M31 distance to better than 5%, thereby leading to
a firmer calibration of the Cosmic Distance Scale and the zeropoint of
H_0.

ACS/WFC 10521

ACS Imaging of a Unique Spitzer Field: Morphology of mid-IR Variable
Sources

We propose to observe the IRAC Dark Field, an extragalactic field 15
arcminutes in diameter near the north ecliptic pole, using 50 orbits
of ACS imaging at I-band. This field is extraordinarily deep and is
uniquely suited to detecting variable objects in the mid-infrared. The
high spatial resolution ACS imaging will be used to derive
morphological information about the galaxies in the field, which will
then be correlated with mid-infrared variable objects {specifically
AGN and supernovae} we have discovered. This field is the dark current
calibration target for the Spitzer Space Telescope, the infrared
counterpart to HST. Because the field is observed frequently as part
of routine operations, it is now similar in size and depth to the
infrared component of the GOODS program, and is confusion-limited in
the mid-infrared. More importantly, due to the periodicity of the
observations, the Spitzer observations are sensitive to variability on
week timescales, ultimately spanning a baseline of five years, and are
the only mid-infrared dataset that will ever have this capability at
this depth. By complementing our wide range of lower resolution
imaging at optical and infrared wavelengths, we hope to exploit one of
HST's most unique capabilities - unparalleled spatial resolution in
the optical. While our specific interest lies in analysis of variable
sources, we will request no proprietary period on the ACS data so that
it may be used by the community to complement the publicly available
Spitzer data.

NIC1/NIC2/NIC3 8794

NICMOS Post-SAA calibration - CR Persistence Part 5

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, ACS/WFC 10802

SHOES-Supernovae, HO, for the Equation of State of Dark energy

The present uncertainty in the value of the Hubble constant {resulting
in an uncertainty in Omega_M} and the paucity of Type Ia supernovae at
redshifts exceeding 1 are now the leading obstacles to determining the
nature of dark energy. We propose a single, integrated set of
observations for Cycle 15 that will provide a 40% improvement in
constraints on dark energy. This program will observe known Cepheids
in six reliable hosts of Type Ia supernovae with NICMOS, reducing the
uncertainty in H_0 by a factor of two because of the smaller
dispersion along the instability strip, the diminished extinction, and
the weaker metallicity dependence in the infrared. In parallel with
ACS, at the same time the NICMOS observations are underway, we will
discover and follow a sample of Type Ia supernovae at z 1. Together,
these measurements, along with prior constraints from WMAP, will
provide a great improvement in HST's ability to distinguish between a
static, cosmological constant and dynamical dark energy. The Hubble
Space Telescope is the only instrument in the world that can make
these IR measurements of Cepheids beyond the Local Group, and it is
the only telescope in the world that can be used to find and follow
supernovae at z 1. Our program exploits both of these unique
capabilities of HST to learn more about one of the greatest mysteries
in science.

NIC3/ACS/WFC 10404

The Nature of Protocluster Galaxies at z=2.16: Morphology-Density and
Color-Magnitude Relations To establish the epoch when galaxy
environment manifests itself as a large-scale evolutionary process, we
propose to extend the study of galaxy colors and morphologies to a
protocluster at z=2.16. Here the universe is only 3 Gyrs old and
significant differences are expected between scenarios favoring a
morphology-radius relation over a morphology-density relation. In
addition, because the fractional age differences among cluster
galaxies are larger, study of the color- magnitude relation provides
considerable leverage for determining the epoch of early-type galaxy
formation. To facilitate direct comparison to studies at lower
redshift, one must probe the same rest-frame wavelengths with high
photometric accuracy and at similar physical scales. Its near-infrared
photometric stability {low, constant background} and ability to image
large areas of sky at high angular-resolution {compared to adaptive
optics} makes HST/NICMOS ideal for this program. Six pointings of
NICMOS camera 3 will result in rest-frame optical, high resolution
images of 16 confirmed protocluster members, and an additional 60
candidate protocluster members including 29 EROs. These galaxies were
selected with a variety of techniques and span a range of projected
radii within the protocluster. The proposed observations constitute a
unique opportunity to extend the study of galaxies in overdense
regions to an early time in cosmic history.

NIC3/ACS/WFC 10921

Tangential Velocities of Objects in the Orion Nebula and Locating the
Embedded Outflow Sources.

The Orion Nebula is arguably the Rosetta Stone for studying a very
young star cluster and how the radiation and outflowing plasma from
its stars interact with ambient material. It has been the subject of
numerous HST imaging studies, which means that there is good
opportunity for determining tangential velocities by obtaining second
epoch images during Cycle 15, which may be the last cycle for which
the WFPC2 is available. These velocities in the plane-of-the-sky will
allow us to determine the patterns of outflow from micro-jets smaller
than the Solar System to jet driven shocks more than a parsec from
their sources. Combined with radial velocities, we'll obtain spatial
velocities, which are critical to determining where the embedded
sources are located that produce the numerous HH objects coming from
the Orion-S and BN-KL regions. We'll also be able to determine the
physics that is operating in the LL Ori type of outflows {where a
bipolar jet is being distorted by a slow wind coming from the nebula}.
We will also be able to search for runaway stars caused by the
disintegration of young multiple-star systems. All of this is possible
because the long-time base of the WFPC2 and ACS observations allow a
new level of astrometric precision to be obtained and to be done
efficiently by making coordinated parallel observations with all
images.

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: (None)

COMPLETED OPS NOTES: (None)

SCHEDULED SUCCESSFUL
FGS GSacq 08 08
FGS REacq 07 07
OBAD with Maneuver 30 30

SIGNIFICANT EVENTS: (None)