This is a deep optical mosaic of the Fornax cluster’s core, covering
1.6 square degrees. The data were acquired with ESO/MPG 2.2m/WFI,
using a transparent filter that nearly equals the no-filter throughput
and thus provides a high signal-to-noise ratio. Based on an
approximate conversion to V-band magnitudes, the unbinned and binned
mosaics (0.24 and 0.71 arcsec/pixel) reach a median depth of 26.6 and
27.8 mag/sq.arcsec, respectively.
Deep Optical Photometry of Six Fields in the Andromeda Galaxy
Short Name:
HST.Andromeda
Date:
22 Jul 2020 22:25:44
Publisher:
Space Telescope Science Institute Archive
Description:
Using the Advanced Camera for Surveys on the Hubble Space Telescope, Thomas Brown
(STScI) et al. obtained deep optical images reaching well below the oldest main
sequence turnoff in six fields of the Andromeda Galaxy. The fields fall at four
positions on the southeast minor axis, one position in the giant stellar stream,
and one position on the northeast major axis. These data were obtained as part of
three large observing programs (9453, 10265, 10816) designed to probe the star
formation history of the stellar population in various structures of the galaxy.
This survey is derived from the 21cm maps presented by Dickey and Lockman
in the <i>ARAA</i> 28, p215. The nH is derived assuming optically thin
emission. The nH given should be considered a lower limit when the nH is
greater than several times 10<sup>20</sup>. Provenance: provided by S. Snowden from data by Dickey and Lockman. This is a service of NASA HEASARC.
The First Byurakan Survey (FBS) is the largest and the first systematic objective prism survey of the extragalactic sky. It covers 17,000 sq.deg. in the Northern sky together with a high galactic latitudes region in the Southern sky. The FBS has been carried out by B.E. Markarian, V.A. Lipovetski and J.A. Stepanian in 1965-1980 with the Byurakan Observatory 102/132/213 cm (40"/52"/84") Schmidt telescope using 1.5 deg. prism. Each FBS plate contains low-dispersion spectra of some 15,000-20,000 objects; the whole survey consists of about 20,000,000 objects.
The Digitized Sky Survey (DSS) is a ground-based imaging survey of the entire sky in several colors. The survey, performed with Palomar and UK Schmidt telescopes, produced photographic plates that were later digitized at the Space Telescope Science Institute (STScI) to produce the Hubble Guide Stars Catalog (GSC).
Each plate produced by the Survey covers 6.5 x 6.5 degrees of the sky, and the plates have been digitized using a modified PDS microdensitometer. The digital images have a pixel size of either 25 microns (1.7 arcsec per pixel) or 15 microns (1.0 arcsec per pixel), and are 14000 x 14000 or 23040 x 23040 pixels per side. The images are stored on 12-inch optical media and are difficult to access quickly.
The Online Digitized Sky Surveys (DSS1 & 2) server at the ESO/ST-ECF Archive provides access to the CD-ROM set produced by the Space Telescope Science Institute through its Guide Star Survey group. The images of these surveys are based on photographic data obtained using the Oschin Schmidt Telescope on Palomar Mountain and the UK Schmidt Telescope. The plates were processed into the present compressed digital form with the permission of these institutions. The photographic plates were scanned to a pixel scale of about 1.7 arcseconds per pixel for the POSS, SERC, and Palomar Quick-V surveys, and to about 1.0 arcseconds per pixel for the POSS-II surveys. Images of any part of the sky may be extracted from the DSS, in either FITS or GIF format.
Roger et al. (1999) presented a map of the 22 MHz radio emission between declinations -28° and +80°,
covering ~73% of the sky, derived from observations with the 22 MHz radiotelescope of the
Dominion Radio Astrophysical Observatory (DRAO).
The resolution of the telescope (EW x NS) is 1.2° x 1.7° secant(zenith angle).
Roger et al. emphasize that the main value of the data lies in the representation of structure
larger than the beam.
The strongest point sources (Cas A, Cyg A, Tau A and Vir A) have been removed from the map.
<p>
The Centre d'Analyse de Données Etendues group used the data to form an all-sky HEALPix format map
following the method described in Appendix A of Paradis et al. 2012, A&A, 543, 103, ADS.
Their HEALPix map is mirrored here.
The map is in units of K brightness temperature.
Map pixels are set to a sentinel value of -32768.0 for unobserved regions and
for regions affected by sidelobes around Cyg A, Tau A, and Vir A. Provenance: DRAO, MPI for Radio Astronomie. This is a service of NASA HEASARC.
![the Fornax VST Survey is licensed under the `Creative Commons Attribution 4.0 License <http://creativecommons.org/licenses/by/4.0/>`_ .. image:: /static/img/ccby.png :alt: [CC-BY]](/registry-search/?f%5BcapabilityType_facet%5D%5B%5D=Simple+Image+Access+Protocol&f%5BcontentLevel_facet%5D%5B%5D=Research&f%5Brights_facet%5D%5B%5D=the+Fornax+VST+Survey+is+licensed+under+the+%60Creative+Commons+Attribution+4.0+License+%3Chttp%3A%2F%2Fcreativecommons.org%2Flicenses%2Fby%2F4.0%2F%3E%60_%0A%0A..+image%3A%3A+%2Fstatic%2Fimg%2Fccby.png%0A+++%3Aalt%3A+%5BCC-BY%5D%0A%0A){kind=link}