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Cooper, Joe December 17th 07 03:29 PM

Daily Report #4508
 
HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science

DAILY REPORT***** # 4508

PERIOD COVERED: UT December 14,15,16, 2007 (DOY 348,349,350)

OBSERVATIONS SCHEDULED

NIC1/NIC2/NIC3 8795

NICMOS Post-SAA calibration - CR Persistence Part 6

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.

FGS 11462

FGS1r, FGS2r, and FGS3 Pre-SM4 Performance

This proposal is the first of a pair of proposals that monitors the
characteristics of HST's two " continuing" Fine Guidance Sensors
across the boundary of the servicing mission SM4. This proposal
obtains the pre-SM4 measurements. Proposal 11463 gathers the same data
but for the post-SM4 baseline. For each FGS, stars from a selected
field in the standard astrometric Galactic cluster M35 are observed in
Position mode. This provides a measurement of their relative
positions, which in turn provides an effective means to detect and
monitor any changes in the FGS optical distortions and plate scales.
If out of tolerance, the need for a re- calibration of the particular
FGS's distortions will be indicated. The FGS-FGS alignments will also
be monitored across the SM boundary. This will be done by using the
same guide star pairs in the corrresponding proposal 11463. Finally,
this proposal and 11463 include Transfer mode observations of selected
M35 stars. These observations will obtain S-curves at the center and
at two off-center field points in each FGS FOV. These data will
provide insight as to whether or not the relative alignment of the FGS
optical train with the HST OTA has changed. If changes larger than
tolerance are observed, it will be necessary to activate the
appropriate contingency proposal that will obtain S-curves are several
locations in the FGS FOV to facilitate a re-computation of the optimal
values of K-factors that are used in the acquisition and tracking of
guide stars (and astrometry targets). This proposal requires a total
of 4 HST orbit to support the FGS2r and FGS3 observations. The FGS1r
observations are available from the FGS Cycle 16 Astrometry
calibration plan.

FGS 11315

Monitoring FGS1r's Interferometric Response as a Function of Spectral
Color

This proposal uses FGS1r in Transfer mode to observe single stars to
obtain the interference fringes of point sources. These data are used
by FGS data analysis tools for studying binary and hierarchical
multiple star systems. Visit 01 observes three stars in M35 over the
FGS1r FOV as a precursor to a corresponding visit in FGS/SM4 proposal
11463.

NIC3 11306

Direct radius measurement of the Neptune-size transiting exoplanet
GJ436b

We propose to measure the radius of the first transiting Neptune-class
extrasolar planet, GJ 436b. The transits of this 22-Earth-mass planet
around a nearby M dwarf were recently detected by our team.
Ground-based photometric observations indicate a planet size
compatible with a Neptune-like structure or an "Ocean Planet". A
direct radius determination from an HST infrared lightcurve will
provide a much more direct measurement of the radius and density of
the planet. GJ 436b is the nearest known transiting exoplanet, as well
as the smallest and lightest, by a large margin. The high
planet-to-star contrast in the infrared make it very favorable for
detailed studies. NICMOS 1-2 microns observations, in addition to
measuring its size, may reveal water absorption from its outer
atmosphere.

ACS/SBC 11215

New Sightlines for the Study of Intergalactic Helium: Dozens of
High-Confidence, UV-Bright Quasars from SDSS/GALEX

The reionization of IGM helium is thought to have occurred at
redshifts of z=3 to 4. Detailed study of HeII Lyman-alpha absorption
toward a handful of QSOs at 2.7z3.3 demonstrated the high potential
of such IGM probes, but the critically small sample size limits
confidence in cosmological inferences. The requisite unobscured
sightlines to high-z are extremely rare, but SDSS provides 5800, z3.1
QSOs potentially suitable for HeII studies. We've cross-correlated
SDSS quasars with GALEX UV sources to obtain dozens of new, high
confidence, candidate sightlines {z=3.1-4.9} potentially useful for
detailed HeII studies with HST. We propose brief, 2-orbit
reconnaissance ACS SBC prism exposures toward each of the best dozen
new quasars, to definitively verify UV flux down to HeII. Our combined
SDSS/GALEX selection insures a high confirmation rate, as the quasars
are already known to be UV bright in GALEX. Our program will provide a
statistical sample of HeII sightlines extending to high redshift,
enabling future long exposure follow-up spectra with the SBC prism, or
superb quality COS or STIS spectra after SM4. Stacks of our prism
spectra will also directly yield ensemble information. Ultimately, the
new sightlines will enable confident measures of the spectrum and
evolution of the ionizing background, the evolution of HeII opacity,
the epoch of helium reionization, and the density of IGM baryons.

FGS 11213

Distances to Eclipsing M Dwarf Binaries

We propose HST FGS observations to measure accurate distances of 5
nearby M dwarf eclipsing binary systems, from which model-independent
luminosities can be calculated. These objects have either poor or no
existing parallax measurements. FGS parallax determinations for these
systems, with their existing dynamic masses determined to better than
0.5%, would serve as model-independent anchor points for the low-mass
end of the mass-luminosity diagram.

FGS 11211

An Astrometric Calibration of Population II Distance Indicators

In 2002 HST produced a highly precise parallax for RR Lyrae. That
measurement resulted in an absolute magnitude, M{V}= 0.61+/-0.11, a
useful result, judged by the over ten refereed citations each year
since. It is, however, unsatisfactory to have the direct,
parallax-based, distance scale of Population II variables based on a
single star. We propose, therefore, to obtain the parallaxes of four
additional RR Lyrae stars and two Population II Cepheids, or W Vir
stars. The Population II Cepheids lie with the RR Lyrae stars on a
common K-band Period-Luminosity relation. Using these parallaxes to
inform that relationship, we anticipate a zero-point error of 0.04
magnitude. This result should greatly strengthen confidence in the
Population II distance scale and increase our understanding of RR
Lyrae star and Pop II Cepheid astrophysics.

WFPC2/NIC2 11193

A comprehensive study of the low-mass stellar population in the
Galactic starburst region NGC 3603

NGC 3603, located in the Carina spiral arm, is one of the most
luminous giant HII regions in the Milky Way, and as such it is often
referred to as a prime template for extragalactic starbursts. While
previous studies were focusing on the high and intermediate mass
stellar content of the central starburst cluster, which powers the HII
region, the effects of the starburst environment with its large number
of ionizing O stars on the emerging low-mass population are unknown.
As the most nearby, most easily accessible starburst, NGC 3603
provides the best testbed to study the long-lived, low-mass stars
originating from a starburst environment. Taking advantage of the
large field of view and high sensitivity of WFPC2, we want to survey
the stellar population in an area of 10pc x 10pc {6' x 6'} down to a
mass limit of 0.2 to 0.5 Mo. This will enable us to derive the total
cluster mass, look for spatial variations in the initial mass
function, determine the age of the dispersed low-mass population in
the HII region and search for evidence of sequential star formation.
Ultimately, we aim at reconstructing the low-mass stellar initial mass
function of the starburst epoch in NGC 3603, which in turn will
advance our understanding of extragalactic starburst phenomena and the
emerging low-mass stars as observed in ancient populations. The
observations of NGC 3603 are part of our larger effort to study
intense star-forming regions in the Milky Way, LMC and SMC.

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 Monte Carlo technique to optimally schedule our
observations.

NIC3 11107

Imaging of Local Lyman Break Galaxy Analogs: New Clues to Galaxy
Formation in the Early Universe

We have used the ultraviolet all-sky imaging survey currently being
conducted by the Galaxy Evolution Explorer {GALEX} to identify for the
first time a rare population of low- redshift starbursts with
properties remarkably similar to high-redshift Lyman Break Galaxies
{LBGs}. These "compact UV luminous galaxies" {UVLGs} resemble LBGs in
terms of size, SFR, surface brightness, mass, metallicity, kinematics,
dust, and color. The UVLG sample offers the unique opportunity of
investigating some very important properties of LBGs that have
remained virtually inaccessible at high redshift: their morphology and
the mechanism that drives their star formation. Therefore, in Cycle 15
we have imaged 7 UVLGs using ACS in order to 1} characterize their
morphology and look for signs of interactions and mergers, and 2}
probe their star formation histories over a variety of timescales. The
images show a striking trend of small-scale mergers turning large
amounts of gas into vigorous starbursts {a process referred to as
dissipational or "wet" merging}. Here, we propose to complete our
sample of 31 LBG analogs using the ACS/SBC F150LP {FUV} and WFPC2
F606W {R} filters in order to create a statistical sample to study the
mechanism that triggers star formation in UVLGs and its implications
for the nature of LBGs. Specifically, we will 1} study the trend
between galaxy merging and SFR in UVLGs, 2} artificially redshift the
FUV images to z=1-4 and compare morphologies with those in similarly
sized samples of LBGs at the same rest-frame wavelengths in e.g.
GOODS, UDF, and COSMOS, 3} determine the presence and morphology of
significant stellar mass in "pre-burst" stars, and 4} study their
immediate environment. Together with our Spitzer {IRAC+MIPS}, GALEX,
SDSS and radio data, the HST observations will form a unique union of
data that may for the first time shed light on how the earliest major
episodes of star formation in high redshift galaxies came about. This
proposal was adapted from an ACS HRC+WFC proposal to meet the new
Cycle 16 observing constraints, and can be carried out using the
ACS/SBC and WFPC2 without compromising our original science goals.

NIC3 11082

NICMOS Imaging of GOODS: Probing the Evolution of the Earliest Massive
Galaxies, Galaxies Beyond Reionization, and the High Redshift Obscured
Universe

(uses ACS/SBC and WFPC2)

Deep near-infrared imaging provides the only avenue towards
understanding a host of astrophysical problems, including: finding
galaxies and AGN at z 7, the evolution of the most massive galaxies,
the triggering of star formation in dusty galaxies, and revealing
properties of obscured AGN. As such, we propose to observe 60 selected
areas of the GOODS North and South fields with NICMOS Camera 3 in the
F160W band pointed at known massive M 10^11 M_0 galaxies at z 2
discovered through deep Spitzer imaging. The depth we will reach {26.5
AB at 5 sigma} in H_160 allows us to study the internal properties of
these galaxies, including their sizes and morphologies, and to
understand how scaling relations such as the Kormendy relationship
evolved. Although NIC3 is out of focus and undersampled, it is
currently our best opportunity to study these galaxies, while also
sampling enough area to perform a general NIR survey 1/3 the size of
an ACS GOODS field. These data will be a significant resource,
invaluable for many other science goals, including discovering high
redshift galaxies at z 7, the evolution of galaxies onto the Hubble
sequence, as well as examining obscured AGN and dusty star formation
at z 1.5. The GOODS fields are the natural location for HST to
perform a deep NICMOS imaging program, as extensive data from space
and ground based observatories such as Chandra, GALEX, Spitzer, NOAO,
Keck, Subaru, VLT, JCMT, and the VLA are currently available for these
regions. Deep high-resolution near-infrared observations are the one
missing ingredient to this survey, filling in an important gap to
create the deepest, largest, and most uniform data set for studying
the faint and distant universe. The importance of these images will
increase with time as new facilities come on line, most notably WFC3
and ALMA, and for the planning of future JWST observations.

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 11037

Red Filters Closeout

This calibration program observes three very red stars {M, L, T
dwarfs} in the five reddest broad and medium filters {F785LP, F791W,
F814W, F850LP, and F1042M} on WF3 in order to allow cross-calibration
to ACS, and in future WFC3. The far-red QE curves will also be tested.
Similar observations on PC1 were made in WFPC2/CAL 10078 and 10366.

WFPC2 11022

WFPC2 Cycle 15 Decontaminations and Associated Observations

This proposal is for the WFPC2 decons. Also included are instrument
monitors tied to decons: photometric stability check, focus monitor,
pre- and post-decon internals {bias, intflats, kspots, & darks}, UV
throughput check, VISFLAT sweep, and internal UV flat check.

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.

FGS 10928

Calibrating Cosmological Chronometers: White Dwarf Masses

We propose to use HST/FGS1R to determine White Dwarf {WD} masses. The
unmatched resolving power of HST/FGS1R will be utilized to follow up
four selected WD binary pairs. This high precision obtained with
HST/FGS1R simply cannot be equaled by any ground based technique. This
proposed effort complements that done by CoI Nelan in which a sample
of WDs is being observed with HST/FGS1R. This proposal will
dramatically increase the number of WDs for which dynamical mass
measurements are possible, enabling a better calibration of the WD
mass-radius relation, cooling curves, initial to final mass relations,
and ultimately giving important clues to the star formation history of
our Galaxy and the age of its disk as well as in other galaxies.

WFPC2 10915

ACS Nearby Galaxy Survey

Existing HST observations of nearby galaxies comprise a sparse and
highly non-uniform archive, making comprehensive comparative studies
among galaxies essentially impossible. We propose to secure HST's
lasting impact on the study of nearby galaxies by undertaking a
systematic, complete, and carefully crafted imaging survey of ALL
galaxies in the Local Universe outside the Local Group. The resulting
images will allow unprecedented measurements of: {1} the star
formation history {SFH} of a 100 Mpc^3 volume of the Universe with a
time resolution of Delta[log{t}]=0.25; {2} correlations between
spatially resolved SFHs and environment; {3} the structure and
properties of thick disks and stellar halos; and {4} the color
distributions, sizes, and specific frequencies of globular and disk
clusters as a function of galaxy mass and environment. To reach these
goals, we will use a combination of wide-field tiling and pointed deep
imaging to obtain uniform data on all 72 galaxies within a
volume-limited sample extending to ~3.5 Mpc, with an extension to the
M81 group. For each galaxy, the wide-field imaging will cover out to
~1.5 times the optical radius and will reach photometric depths of at
least 2 magnitudes below the tip of the red giant branch throughout
the limits of the survey volume. One additional deep pointing per
galaxy will reach SNR~10 for red clump stars, sufficient to recover
the ancient SFH from the color-magnitude diagram. This proposal will
produce photometric information for ~100 million stars {comparable to
the number in the SDSS survey} and uniform multi- color images of half
a square degree of sky. The resulting archive will establish the
fundamental optical database for nearby galaxies, in preparation for
the shift of high- resolution imaging to the near-infrared.

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.

NIC3 10874

Search for Extremely Faint z7 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 z7
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 unprecendented 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 z7 will facilitate
the models of the IGM reionization and future JWST planning.

ACS/SBC 10872

Lyman Continuum Emission in Galaxies at z=1.2

Lyman continuum photons produced in massive starbursts may have played
a dominant role in the reionization of the Universe. Starbursts are
important contributors to the ionizing metagalactic background at
lower redshifts as well. However, their contribution to the background
depends upon the fraction of ionizing radiation that escapes from the
intrinsic opacity of galaxies below the Lyman limit. Current surveys
suggest escape fractions of a few percent, up to 10%, with very few
detections {as opposed to upper limits} having been reported. No
detections have been reported in the epochs between z=0.1 and z=2. We
propose to measure the fraction of escaping Lyman continuum radiation
from 15 luminous z~1.2 galaxies in the GOODS fields. Using the
tremendous sensitivity of the ACS Solar- blind Channel, we will reach
AB=30 mag., allowing us to detect an escape fraction of 1%. We will
correlate the amount of escaping radiation with the photometric and
morphological properties of the galaxies. A non-detection in all
sources would imply that QSOs provide the overwhelming majority of
ionizing radiation at z=1.3, and it would strongly indicate that the
properties of galaxies at higher redshift have to be significantly
different for galaxies to dominate reionization. The deep FUV images
will also be useful for extending the FUV study of other galaxies in
the GOODS fields.

WFPC2 10812

Space Motions for the Draco and Sextans Dwarf Spheroidal Galaxies

We will use the powerful astrometric capabilities of HST to measure
proper motions for the Draco and Sextans dwarf spheroidal galaxies
that will yield tangential velocities accurate to about 30 km/s. These
two galaxies are the last inside a galactocentric radius of 200~kpc
without measured proper motions. Knowing their orbits is critical for
our understanding of the low-luminosity satellites of the Milky Way.
In particular they are critical for understanding why Ursa Minor has
survived tidal disruption on its plunging orbit and how Carina formed
a large intermediate-age stellar population despite its small mass.

FLIGHT OPERATIONS SUMMARY:

Significant Spacecraft Anomalies: (The following are preliminary
reports of potential non-nominal performance that will be
investigated.)

HSTARS:

11100 - REACQ(2,1,2) fine lock backup on FGS 2

REACQ(2,1,2) at 348/19:23:02 acquired in fine lock backup on FGS 2
only, with QF1STOPF and QSTOP flags set on FGS 1 at 19:27:37. No other
flags were seen. Previous acquisition at 17:50:11 was successful.

11101 - GSAcq(2,3,2) failed to RGA Hold(gyro Control)

GSAcq(2,3,2) scheduled at 349/19:15:18 - 19:23:23 failed to RGA Hold
due to (QF2STOPF) stop flag indication on FGS-2 during acquisition
walkdown. Scheduled Astrometry FGS1 did not attempt. Pre-acquisition
OBADs had (RSS) values of 931.61 and 4.46 arcseconds.

OBAD/MAP scheduled at 349/19:23:23 had 3-axis (RSS) value of 4.18
arcseconds.

11102 - GSAcq(1,2,1) failed to RGA Hold

At AOS (350/00:51:00) observed that GSAcq (1,2,1) scheduled from
00:41:58 - 00:49:52 had failed to RGA Hold due to QSTOP & QF2STOPF
flags on FGS 2. No 486 ESB messages were received. Due to LOS, the
data from OBAD 1 is unavailable till an engineering data dump is
performed. OBAD 2 data showed the following results: V1 1.39, V2 4.19,
V3 3.00, RSS 5.34.

OBAD MAP at 01:38:52 showed the following results: V1 -2.38, V2
-11.86, V3 9.58, RSS 15.43

REAcq(1,2,1) @ 350/02:06:00 was successful

11103 - GSAcq(2,1,2) results in finelock backup (2,0,2) using FGS-2

Upon acquisition of signal at 350/20:35:20, the GSAcq(2,1,2) scheduled
at 350/19:33:11 - 19:41:16 had resulted to finelock backup (2,0,2)
using FGS-2,due to stop flag (QF1STOPF) indication on FGS-1.
Pre-acquisition OBAD1 had attitude error correction (RSS) value of
1824.19 arcseconds. OBAD2 attitude error correction (RSS) not
available pending future ETR Dump. Post-acq OBAD/MAP had (RSS) value
of 19.65 arcseconds. Subsequent

REacq(2,1,2) scheduled at 350/21:07:49 using same guide star pair
resulted to finelock backup (2,0,2) using FGS-2 due to stop flag on
FGS-1.

11104 - GSAcq(1,2,2) resulted in Fine Lock Back-up (1,0,1)

GSAcq (1,2,2) scheduled from 09:36:13 - 09:43:26 resulted in Fine Lock
Back-up (1,0,1) using FGS 1. This was due to QF2STOPF flag on FGS 2
and QSTOP flag. At 09:39:50 received 486 ESB message 1808 "TxG FHST
Sanity Check Failed". Pre-acquisition OBAD1 had attitude error
correction (RSS) value of 2691.62 arcseconds. Pre-acquisition OBAD2
had attitude error correction (RSS) value of 5.39 arcseconds. Post
acquisition OBAD MAP was not scheduled.

COMPLETED OPS REQUEST: (None)

COMPLETED OPS NOTES: (None)

*********************** SCHEDULED***** SUCCESSFUL

FGS GSacq************** 27***************** 25
FGS REacq************** 17***************** 17
OBAD with Maneuver **** 88***************** 88

SIGNIFICANT EVENTS:

FSW 3.1 Release B was successfully installed into HST486 EEPROM at
348/13:00:34. The load completed successfully and the valid block
counter was verified. The post installation EEPROM dump was completed
at 348/15:16:59, and the Compare Best Estimate of the dump file
against the EEPROM load showed no miscompares and no missing blocks.
FSW also verified the contents of the memory dump.




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