HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science

 

DAILY REPORT #4896

 

PERIOD COVERED: 5am July 27 - 5am July 28, 2009 (DOY 208/09:00z-209/09:00z)

 

OBSERVATIONS SCHEDULED

 

COS 11478

 

COS NUV Flat Fields

 

Acquire long NUV flat field exposures using the internal deuterium

calibration lamp with the G185M grating. Use central wavelengths of 1835

angstroms, 1850 angstroms, and 1864 angstroms. Based on data taken

during thermal vacuum testing in 2003 (Test 1750), a total of 65,000

seconds of data should be sufficient to obtain ~7.5x10^7 total counts in

the science region of the detector (> 200 counts per pixel, or 1800

counts per 3 x 3 pixel resolution element).

 

This is SMOV4 Activity COS-18.

 

COS 11485

 

COS Internal FUV Wavelength Measurement

 

Obtain an initial set of FUV wavelength calibration exposures with

internal PtNe lamp 1 for each FUV grating and central wavelength

combination. A more limited set of exposures to test operation of

internal PtNe lamp 2 will be obtained in separate program 11496. Lamp 1

exposures wil be used to establish the limits of the initial wavelength

scales and to determine if adjustments are necessary.

 

COS 11487

 

COS FUV Internal/External Wavelength Scales

 

Observe external radial velocity standard targets in TIME-TAG

(FLASH=YES) mode with all grating and central wavelength combinations.

The purpose is to obtain zero-point offsets for the wavelength scale

(internal wavecal lamp scale to external standard wavelength scale) and

PSA dispersion relations for all central wavelengths.

 

Following this determination, adjustments of the nominal science target

spectral range for each grating and central wavelength combination will

be made via SMS patchable constant for nominal OSM1 positions

corresponding to each central wavelength. Subsequent to this

modification of the wavelength scale (and its verification via analysis

of COS30 - program 11488), FUV science-related operations and

wavelength- dependent EROs can commence.

 

COS 11496

 

SMOV Verification of COS PtNe Lamp 2

 

Obtain an initial set of wavelength calibration exposures with internal

PtNe lamp 2 at one central wavelength for each FUV and NUV grating.

Additionally, obtain NUV test exposures with MIRRORA and MIRRORB for

PtNe lamp 2. Initial lamp wavelength calibration exposures will be

obtained in separate proposals.

 

The program also executes the COS NUV grating efficiency test (GET) in

two sections separated by 20-25 minutes of lamp cooling time. The

cooling time allows the lamp to cool back to its state prior to the

first half of the test. .Each section of the test contains of 10 NUV

exposures designed to get the same S/N of various emission lines

throughout the NUV band.

 

STIS07 11404

 

CCD Dark and Bias Monitor for SMOV4/Cycle 17 Activity STIS-07

 

Monitor the darks for the STIS CCD. Monitor the bias in the 1x1, 1x2,

2x1, and 2x2 bin settings at gain=1, and 1x1 at gain = 4, to build up

high-S/N superbiases and track the evolution of hot columns.

 

WFC3 11447

 

WFC3 IR Dark Current, Readnoise, and Background

 

This proposal obtains full-frame, four-amp readout images.

Un-illuminated internals are taken at regularly spaced intervals

throughout SMOV in order to assess and monitor readnoise and dark

current (of both light-sensitive pixels and reference pixels), and bad

(warm, hot, dead, variable) pixels. In addition, externals aimed at

fields with sparse stellar density are taken to measure diffuse

background light.

 

This program corresponds to WFC3-34.

 

WFC3 11808

 

WFC3 UVIS Bowtie Monitor

 

The UVIS detector was observed during ground testing to occasionally

exhibit flat field and dark variations with a bowtie pattern. These

variations are most significant as ~1% flat field (gain) variations

across the field of view. It is believed that this represents a state or

condition into which the detector can transition for reasons and under

circumstances which are not currently understood. It is also very

unlikely that most science observations will determine the state (bowtie

or no-bowtie) of the detector. Ground test data indicates that this

state is long lived (many hours to ~one day). Hysteresis or memory of

past light exposure is also associated with this state.

 

Recent evidence suggests that exposing the detector to ~200k to 500k

electrons may quench this state. This proposal obtains an internal flat

field sequence of three exposures: one at 10x full well with two at 0.5x

full well immediately before and after. Each exposure is 3x3 binned to

reduce the data volume required.

 

These visits should be scheduled 2x per day until further direction is

provided.

 

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: 

18652-0 - Genslew for proposal 11474 (slot #2) @ 208/1501z

18653-0 - Genslew for proposal 11474 (slot #3) @ 208/1503z

18654-0 - Genslew for proposal 11474 (slot #4) @ 208/1510z

18655-0 - Update COS OSM2 FSW mech positions for G285M @ 208/2346z

18643-1 - NCS Restart and Cool Down (steps #1-11) @ 209/01:34z        

 

 

COMPLETED OPS NOTES: (None)

 

                               SCHEDULED      SUCCESSFUL     

FGS GSAcq                        4                    4              

FGS REAcq                        11                  11                                                                                                

OBAD with Maneuver          3                    3  

 

SIGNIFICANT EVENTS:

NCS pre-conditioning for DOY 209 planned restart was completed with

the execution of the first eleven steps of OR 18643-1 NCS Restart and

Cool down at 209/01:34z.