HUBBLE SPACE TELESCOPE - Continuing to collect World
Class Science
DAILY REPORT #4779
PERIOD COVERED: 5am January 27 - 5am January 28, 2009
(DOY
027/1000z-028/1000z)
OBSERVATIONS SCHEDULED
WFPC2 10877
A Snapshot Survey of the Sites of Recent, Nearby
Supernovae
During the past few years, robotic {or nearly robotic}
searches for
supernovae {SNe}, most notably our Lick Observatory Supernova
Search
{LOSS}, have found hundreds of SNe, many of them in quite
nearby
galaxies {cz < 4000 km/s}. Most of the objects were discovered
before
maximum brightness, and have follow-up photometry and spectroscopy;
they
include some of the best-studied SNe to date. We propose to conduct
a
snapshot imaging survey of the sites of some of these nearby objects,
to
obtain late-time photometry that {through the shape of the light
and
color curves} will help reveal the origin of their lingering energy.
The
images will also provide high-resolution information on the
local
environments of SNe that are far superior to what we can procure
from
the ground. For example, we will obtain color-color and
color-magnitude
diagrams of stars in these SN sites, to determine the SN
progenitor
masses and constraints on the reddening. Recovery of the SNe in
the new
HST images will also allow us to actually pinpoint their
progenitor
stars in cases where pre- explosion images exist in the HST
archive.
This proposal is an extension of our successful Cycle 13 snapshot
survey
with ACS. It is complementary to our Cycle 15 archival proposal,
which
is a continuation of our long-standing program to use existing
HST
images to glean information about SN environments.
ACS/SBC 11566
Imaging Saturn's Equinoctal Auroras
Auroral emissions provide an indispensable diagnostic
tool for the
energetic processes occurring in planetary magnetospheres. In
2009
Saturn will reach equinox for the first time since the advent
of
high-sensitivity planetary ultraviolet (UV) auroral imaging, offering
a
unique, transient opportunity to observe both polar auroral
regions
simultaneously. The observations proposed here will not only provide
the
best images to date of Saturn's
northern auroras, they will address
three fundamental issues: (1) Are
Saturn's auroras similar in the
north
and south? This will reveal the nature of the processes that cause
the
northern auroras, and verify the multipole nature of Saturns
internal
magnetic field. (2) Is the location of the northern auroral
emission
symmetric with to the south? This will indicate why the southern
auroral
oval is displaced a few degrees toward midnight from the spin pole.
It
will also reveal whether the oscillation observed in the location of
the
southern auroral oval is similarly observed in the north,
illuminating
the nature of near-planetary period oscillations observed
throughout the
magnetosphere and potentially providing a value for the
elusive rotation
period of the deep interior. (3) What is the influence of
equinox on the
magnetosphere? The unique orientation of the planetary spin
axis at
equinox will reveal whether the auroras are influenced by the
direction
of the interplanetary magnetic field, and whether the Sun's effect on
Saturn's magnetosphere changes throughout the
planet's seasons. The
Hubble Space
Telescope is the only instrument capable of providing
global instantaneous
coverage of Saturn's UV auroras, and since
Saturn's
orbital period is ~30 years,
Cycle 17 is the only opportunity to make
these observations.
FGS 11943/11944
Binaries at the Extremes of the H-R Diagram
We propose to use HST/Fine Guidance Sensor 1r to survey
for binaries
among some of the most massive, least massive, and oldest stars
in our
part of the Galaxy. FGS allows us to spatially resolve binary
systems
that are too faint for ground-based, speckle or optical long
baseline
interferometry, and too close to resolve with AO. We propose
a
SNAP-style program of single orbit FGS TRANS mode observations of
very
massive stars in the cluster NGC 3603, luminous blue variables,
nearby
low mass main sequence stars, cool subdwarf stars, and white
dwarfs.
These observations will help us to (1) identify systems suitable
for
follow up studies for mass determination, (2) study the role of
binaries
in stellar birth and in advanced evolutionary states, (3) explore
the
fundamental properties of stars near the main sequence-brown
dwarf
boundary, (4) understand the role of binaries for X-ray bright
systems,
(5) find binaries among ancient and nearby subdwarf stars, and (6)
help
calibrate the white dwarf mass - radius relation.
WFPC2 11103
A Snapshot Survey of The Most Massive Clusters of
Galaxies
We propose the continuation of our highly successful
SNAPshot survey of
a sample of 125 very X-ray luminous clusters in the
redshift range
0.3-0.7. As demonstrated by the 25 snapshots obtained so far
in Cycle14
and Cycle15 these systems frequently exhibit strong
gravitational
lensing as well as spectacular examples of violent galaxy
interactions.
The proposed observations will provide important constraints on
the
cluster mass distributions, the physical nature of galaxy-galaxy
and
galaxy-gas interactions in cluster cores, and a set of optically
bright,
lensed galaxies for further 8-10m spectroscopy. All of our
primary
science goals require only the detection and characterization
of
high-surface-brightness features and are thus achievable even at
the
reduced sensitivity of WFPC2. Because of their high redshift and
thus
compact angular scale our target clusters are less adversely affected
by
the smaller field of view of WFPC2 than more nearby
systems.
Acknowledging the broad community interest in this sample we waive
our
data rights for these observations.
FLIGHT OPERATIONS SUMMARY:
Significant Spacecraft Anomalies: (The following are
preliminary reports
of potential non-nominal performance that will be
investigated.)
HSTARS:
11650 - GSAcq (1,2,2) scheduled
from 027/12:44:20 - 027/12:51:27 failed at
12:48:20 due to QF1STOPF and QSTOP flags on FGS-1.
Observations affected: WFPC 38 - 41,
Proposal# 10877.
COMPLETED OPS
REQUEST:
18394-3 - Uplink new FHST Alignments
COMPLETED OPS NOTES: (None)
SCHEDULED SUCCESSFUL
FGS
GSacq
12 11
FGS
REacq
00 00
OBAD with
Maneuver
24
24
SIGNIFICANT EVENTS:
Flash Reports:
Ops Request 18394 was successfully executed
approximately 027/13:55 -
13:52 to update the T2G Database for the FHST
Alignments.