Notice: Due to the conversion of some ACS WFC or HRC
observations into
WFPC2, or NICMOS observations after
the loss of ACS CCD science
capability in January, there may be an
occasional discrepancy between a
proposal's listed (and correct) instrument
usage and the abstract that
follows it.
HUBBLE SPACE TELESCOPE - Continuing to collect World Class
Science
DAILY REPORT # 4412
PERIOD COVERED: UT July 25, 2007 (DOY 206)
OBSERVATIONS SCHEDULED
FGS 11295
Trigonometric Calibration of the Distance Scale for
Classical Novae
The distance scale for classical novae is important for
understanding
the stellar physics of their
thermonuclear runaways, their contribution
to Galactic nucleosynthesis,
and their use as extragalactic standard
candles. Although it is known that
there is a relationship between their
absolute magnitudes at maximum light and
their subsequent rates of
decline--the well-known
maximum-magnitude rate-of-decline {MMRD}
relation--it is difficult to set the
zero-point for the MMRD because of
the very uncertain distances of
Galactic novae. We propose to measure
precise trigonometric parallaxes for
the quiescent remnants of the four
nearest classical novae. We will use
the Fine Guidance Sensors, which
are proven to be capable of
measuring parallaxes with errors of ~0.2
mas, well below what is possible
from the ground.
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 DARKs. 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.
NIC3 10874
Search for Extremely Faint z>7 Galaxy Population with
Cosmic Lenses
Deep UDF/NICMOS observations find a significant decrease
in the number
of galaxy candidates between redshift z=6 and 7, but the sample at z>7
is too small to draw conclusions.
From our observations of 15 clusters
we have found a number of bright
z-dropouts, aided by the lensing
amplification. We propose deep NICMOS
observations of the best cases of
cluster centers where a rare
combination of a significant lensing effect
and the richness in z-band dropouts
in background may dramatically
increase the discovery rate. The NICMOS
images will reach an
unprecedented depth of AB~27.8, or AB~30 in nonlensed intrinsic
magnitude, and may find many faint
{~0.05L*} galaxies at z=7-10, at a
level that the UDF reaches for z~6
objects. We produce precision mass
distribution maps from weak-lensing models, which enable us to derive
the candidates' intrinsic
magnitudes and their luminosity function. The
knowledge of such faint galaxy population
at z>7 will facilitate the
models of the IGM reionization
and future JWST planning.
WFPC2 11081
RR Lyrae stars in M31 Globular
Clusters: How did the M31 Spiral Galaxy
Form?
The pulsation properties of the RR Lyrae
stars in the globular clusters
of the Andromeda galaxy {M31} have
the potential to provide essential
insight on the first epoch of the
galaxy formation and to trace the
merging episodes that led to the
assembly of M31. Their mean periods
along with the cluster metallicities can provide an independent estimate
of the M31 cluster ages and, in
turn, of the time scale of the M31 halo
formation, by comparison with their Milky
Way counterparts. We will
observe RR Lyrae
stars in 6 appropriately selected globular clusters of
M31 using WFPC2 to derive periods, light curves, and
physical parameters
of these eyewitnesses of the first
epochs of the M31 formation.
WFPC2 11178
Probing Solar System History with Orbits, Masses, and
Colors of
Transneptunian Binaries
The recent discovery of numerous transneptunian
binaries {TNBs} opens a
window into dynamical conditions in
the protoplanetary disk where they
formed as well as the history of
subsequent events which sculpted the
outer Solar System and emplaced them
onto their present day heliocentric
orbits. To date, at least 47 TNBs have been discovered, but only about a
dozen have had their mutual orbits
and separate colors determined,
frustrating their use to investigate
numerous important scientific
questions. The current shortage of data
especially cripples scientific
investigations requiring statistical
comparisons among the ensemble
characteristics. We propose to obtain
sufficient astrometry and
photometry of 23 TNBs
to compute their mutual orbits and system masses
and to determine separate primary
and secondary colors, roughly tripling
the sample for which this
information is known, as well as extending it
to include systems of two
near-equal size bodies. To make the most
efficient possible use of HST, we will
use a
optimally schedule our observations.
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 3 3
FGS REacq 12 12
OBAD with Maneuver
30 30
SIGNIFICANT EVENTS: (None)
-
____________________________________________________________
Lynn F. Bassford
Hubble Space Telescope
CHAMP Mission Operations Manager
Lockheed Martin Mission Services (LMMS)
NASA GSFC PH#: 301-286-2876
"The Hubble Space Telescope is the
astronomical observatory and key to unlocking the most cosmic mysteries of the
past, present and future." - 7/26/6