Hubble Space Telescope ACS Nearby Galaxy Survey (ANGST)
Short Name:
HST.angst
Date:
23 Jul 2020 19:38:15
Publisher:
Space Telescope Science Institute Archive
Description:
The ACS Nearby Galaxy Survey observed roughly 14 million stars in 69 galaxies. The survey explored a region called the "Local Volume," and the galaxy distances ranged from 6.5 million light-years to 13 million light-years from Earth. The Local Volume resides beyond the Local Group of galaxies, an even nearer collection of a few dozen galaxies within about 3 million light-years of our Milky Way Galaxy. The observations were made in November 2006 with Hubble's Advanced Camera for Surveysi (ACS).
Hubble Space Telescope Heritage Press Release Images
Short Name:
HST.heritage
Date:
23 Jul 2020 19:38:59
Publisher:
Space Telescope Science Institute Archive
Description:
WFPC2 and ACS images used to create the Heritage project color composite press releases. The data has been expertly prepared, significantly beyond the standard pipeline processing. This usually involves careful image registration, combination, and cleaning via drizzling, making it ready for further scientific analysis and educational use. These data will typically be made available at the time of the associated press release.
Hubble Space Telescope multi-color ACS mosaic of M82
Short Name:
HST.M82
Date:
23 Jul 2020 19:39:46
Publisher:
Space Telescope Science Institute Archive
Description:
In March 2006, the Hubble Heritage Team obtained a large 4-color (B, V, I, and H-alpha) mosaic image of the M82 with the Advanced Camera for Surveys (ACS) onboard the Hubble Space Telescope.
This paper presents the Hubble Ultra Deep Field (HUDF), a 1 million secs exposure of an 11arcmin^2^ region in the southern sky with the Advanced Camera for Surveys on the Hubble Space Telescope using Director's Discretionary Time. The exposure time was divided among four filters, F435W (B435), F606W (V606), F775W (i775), and F850LP (z850), to give approximately uniform limiting magnitudes m_AB_~29 for point sources. The image contains at least 10000 objects, presented here as a catalog, the vast majority of which are galaxies. Visual inspection of the images shows few if any galaxies at redshifts greater than ~4 that resemble present-day spiral or elliptical galaxies. The image reinforces the conclusion from the original Hubble Deep Field that galaxies evolved strongly during the first few billion years in the infancy of the universe. Using the Lyman break dropout method to derive samples of galaxies at redshifts between 4 and 7, it is possible to study the apparent evolution of the galaxy luminosity function and number density.
The Hubble Ultra Deep Field (PI: Steven V. W. Beckwith) is a 400-orbit Cycle 12 program to image a single field of the Wide Field Camera (WFC) of the Advanced Camera for Surveys (ACS) in four filters: F435W (B), F606W (V), F775W (i), and F850LP (z). The observations took place over 4 months from September 2003 to January 2004 under two program IDs: 9978 and 10086. The observations consist of half-orbit exposures, cycling through each of the filters in a 4-point dither pattern to provide sub-pixel sampling, as well as a larger-scale 3-point line pattern to cover the 2 second of arc gap between the two ACS/WFC chips. The total exposure times are summarized below, with typical exposure times of 1200s for individual images. The AB magnitude zero-points for ACS are current as of March 2004. --------------------------------------------------------------- Number of Number of Total Exp. AB mag. Orbits Exposures Time (s) zero-point --------------------------------------------------------------- B (F435W): 56 112 134880 25.673 V (F606W): 56 112 135320 26.486 i (F775W): 144 288 347110 25.654 z (F850LP): 144 288 346620 24.862 --------------------------------------------------------------- More details are found in the "intro.txt" file, or from the UDF home page.
The Hubble Ultra Deep Field 2009 (HUDF09) program observations were obtained as HST program 11563 (PI: Garth Illingworth) from August 2009 to February 2011 (Cycle 17). The program uses WFC3/IR as the prime instrument for 192 orbits to image the deep ACS fields that were obtained in the original HUDF (PI: Steven Beckwith) program and in the HUDF05 (PI: Massimo Stiavelli) program.
The data are organized into sets of images by HUDF09 pointing and by passband (WFC3/IR F105W, F125W & F160W). Each image is approximately 3k x 3k pixels in size and a scale of 0.06 arcsec/pixel. All three pointings reside in the GOODS/Chandra South field and each pointing includes a drizzled science image and a weight image.
We report on the i-dropouts detected in two exceptionally deep Advanced Camera for Surveys fields (B_435_, V_606_, i_775_, and z_850_ with 10{sigma} limits of 28.8, 29.0, 28.5, and 27.8, respectively) taken in parallel with the Ultra Deep Field Near-Infrared Camera and Multi-Object Spectrometer observations. Using an i-z>1.4 cut, we find 30 i-dropouts over 21-arcmin^2^ down to z_(850,AB)_=28.1, or 1.4 i-dropouts arcmin^-2^, with significant field-to-field variation (as expected from cosmic variance). This extends i-dropout searches some ~0.9mag further down the luminosity function than was possible in the Great Observatories Origins Deep Survey (GOODS) fields, yielding a ~7 times increase in surface density. An estimate of the size evolution for UV-bright objects is obtained by comparing the composite radial flux profile of the bright i-dropouts (z_(850,AB)_<27.2) with scaled versions of the Hubble Deep Field North and South U-dropouts.
The catalog contains all published HI observations (21cm) of external galaxies published until the middle of 1988. It contains almost 20,000 entries for over 10,000 galaxies based on more than 570 references. The HI data are basically just as they were originally published -- no numerical conversions were made and no error correction was attempted.
We use ultra-deep Hubble Space Telescope Wide Field Camera 3/infrared imaging of the Hubble Ultra Deep Field to investigate the rest-frame optical morphologies of a mass-selected sample of galaxies at z~2. We find a large variety of galaxy morphologies, ranging from large, blue, disk-like galaxies to compact, red, early-type galaxies. We derive rest-frame u-g color profiles for these galaxies and show that most z~2 galaxies in our sample have negative color gradients such that their cores are red.
Spectroscopic observations have been carried out for galaxies in the Milky Way with the 1.9m telescope of the South African Astronomical Observatory (SAAO). The galaxies were selected from a deep optical galaxy search covering 266deg<~l<~296deg, |b|<~10deg (Kraan-Korteweg 1994). This is in the extension of the Hydra and Antlia clusters and in the approximate direction of the dipole anisotropy in the Cosmic Microwave Background radiation.