Notice: For the foreseeable future, the daily reports may contain

apparent discrepancies between some proposal descriptions and the listed

instrument usage. This is due to the conversion of previously approved

ACS WFC or HRC observations into WFPC2, or NICMOS observations

subsequent to the loss of ACS CCD science capability in late January.

 

 

HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science

 

DAILY REPORT       # 4313

 

PERIOD COVERED: UT March 06, 2007 (DOY 065)

 

OBSERVATIONS SCHEDULED

 

ACS/SBC 10862

 

Comprehensive Auroral Imaging of Jupiter and Saturn during the

International Heliophysical Year

 

A comprehensive set of observations of the auroral emissions from

Jupiter and Saturn is proposed for the International Heliophysical Year

in 2007, a unique period of especially concentrated measurements of

space physics phenomena throughout the solar system. We propose to

determine the physical relationship of the various auroral processes at

Jupiter and Saturn with conditions in the solar wind at each planet.

This can be accomplished with campaigns of observations, with a sampling

interval not to exceed one day, covering at least one solar rotation.

The solar wind plasma density approaching Jupiter will be measured by

the New Horizons spacecraft, and a separate campaign near opposition in

May 2007 will determine the effect of large-scale variations in the

interplanetary magnetic field {IMF} on the Jovian aurora by

extrapolation from near-Earth solar wind measurements. A similar Saturn

campaign near opposition in Jan. 2007 will combine extrapolated solar

wind data with measurements from a wide range of locations within the

Saturn magnetosphere by Cassini. In the course of making these

observations, it will be possible to fully map the auroral footprints of

Io and the other satellites to determine both the local magnetic field

geometry and the controlling factors in the electromagnetic interaction

of each satellite with the corotating magnetic field and plasma density.

Also in the course of making these observations, the auroral emission

properties will be compared with the properties of the near-IR

ionospheric emissions {from ground-based observations} and non thermal

radio emissions, from ground-based observations for Jupiter?s decametric

radiation and Cassini plasma wave measurements of the Saturn Kilometric

Radiation {SKR}.

 

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 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 11080

 

Exploring the Scaling Laws of Star Formation

 

As a variety of surveys of the local and distant Universe are

approaching a full census of galaxy populations, our attention needs to

turn towards understanding and quantifying the physical mechanisms that

trigger and regulate the large-scale star formation rates {SFRs} in

galaxies.

 

WFPC2 11083

 

The Structure, Formation and Evolution of Galactic Cores and Nuclei

 

A surprising result has emerged from the ACS Virgo Cluster Survey

{ACSVCS}, a program to obtain ACS/WFC gz imaging for a large, unbiased

sample of 100 early-type galaxies in the Virgo Cluster. On subarcsecond

scales {i.e., <0.1"-1"}, the HST brightness profiles vary systematically

from the brightest giants {which have nearly constant surface brightness

cores} to the faintest dwarfs {which have compact stellar nuclei}.

Remarkably, the fraction of galaxy mass contributed by the nuclei in the

faint galaxies is identical to that contributed by supermassive black

holes in the bright galaxies {0.2%}. These findings strongly suggest

that a single mechanism is responsible for both types of Central Massive

Object: most likely internally or externally modulated gas inflows that

feed central black holes or lead to the formation of "nuclear star

clusters". Understanding the history of gas accretion, star formation

and chemical enrichment on subarcsecond scales has thus emerged as the

single most pressing question in the study of nearby galactic nuclei,

either active or quiescent. We propose an ambitious HST program {199

orbits} that constitutes the next, obvious step forward:

high-resolution, ultraviolet {WFPC2/F255W} and infrared {NIC1/F160W}

imaging for the complete ACSVCS sample. By capitalizing on HST's unique

ability to provide high-resolution images with a sharp and stable PSF at

UV and IR wavelengths, we will leverage the existing optical HST data to

obtain the most complete picture currently possible for the history of

star formation and chemical enrichment on these small scales. Equally

important, this program will lead to a significant improvement in the

measured structural parameters and density distributions for the stellar

nuclei and the underlying galaxies, and provide a sensitive measure of

"frosting" by young stars in the galaxy cores. By virtue of its superb

image quality and stable PSF, NICMOS is the sole instrument capable of

the IR observations proposed here. In the case of the WFPC2

observations, high-resolution UV imaging {< 0.1"} is a capability unique

to HST, yet one that could be lost at any any time.

 

WFPC2 11020

 

Cycle 15 Focus Monitor

 

The focus of HST is measured primarily with ACS/HRC over full CVZ orbits

to obtain accurate mean focus values via a well sampled breathing curve.

Coma and astigmatism are also determined from the same data in order to

further understand orbital effects on image quality and optical

alignments. To monitor the stability of ACS to WFPC2 relative focii,

we've carried over from previous focus monitor programs parallel

observations taken with the two cameras at suitable orientations of

previously observed targets, and interspersed them with the HRC CVZ

visits.

 

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               10                  10                  

FGS REacq               06                  06                  

OBAD with Maneuver 32                  32                                  

 

SIGNIFICANT EVENTS: (None)