![]() ![]() When using data from the CANDELS survey, please include the following acknowledgement: Another alternative is to not use Astropy but instead use WCSTools, available from CfA, which also correctly calculates astrometry for these mosaics. A solution is instead to use the Astropy tools "wcs_pix2world" or "wcs_world2pix" (also contained in "wcs"), which do not make this error and which give correct astrometry for these mosaics. However, the Astropy tools "all_pix2world" or "all_world2pix" (contained in "wcs") currently attempt to apply SIP coefficients that are found in the headers, and therefore may not give correct astrometry. Their CTYPE keywords also correctly reflect this (being set to "RA-TAN" and "DEC-TAN'). Note:Īll the mosaics provided here have already had all distortion removed by drizzling, and correct astrometry is provided in their header WCS (represented by CRVAL1, CRVAL2, CRPIX1, CRPIX2, CD1_1, CD1_2, CD2_1, CD2_2). Additional information about the survey design is available on the CANDELS public web site. In combination with ultra-deep imaging from the Hubble Ultradeep Field program ( GO 11563), the result is a three-tiered strategy that effciently samples both bright/rare and faint/common extragalactic objects. It also includes a "Deep" imaging survey to ~12-orbit Y+J+H depth in the two GOODS fields, tiling ~60 sq. arcmin in the COSMOS, EGS, and UDS fields. It will also discover and characterize Type Ia SNe beyond z > 1.5 and establish their accuracy as standard candles for cosmology. The program incorporates a "Wide" imaging survey to two-orbit J+H depth over 720 sq. The Cosmic Assembly Near-IR Deep Extragalactic Legacy Survey (CANDELS) is designed to document the first third of galactic evolution from z = 8 to 1.5 via deep imaging of more than 250,000 galaxies with WFC3/IR and ACS. ![]()
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