The Legacy Survey will cover 14,000 square degrees of the extragalactic sky, and yield high-quality optical and near-infrared photometric catalogs. The sky coverage is approximately bounded by -18° < δ < +84° in celestial coordinates and |b| > 18° in Galactic coordinates. Resulting images, models, and catalogs will enhance current and future wide area surveys such as SDSS/BOSS/eBOSS and DESI.
The Legacy Survey is a combination of the DECam Legacy Survey (DECaLS) using the Dark Energy Camera on the Blanco 4m telescope, the Mayall z-band Legacy Survey (MzLS) using the MOSAIC instrument on the Mayall 4m telescope, and the Beijing-Arizona Sky Survey (BASS) using the 90Prime instrument at the Steward Observatory Bok telescope.
|DECaLS||Blanco||g, r, z||9500 sq. deg|
|MzLS||Mayall||z||5000 sq. deg|
|BASS||Bok||g, r||5000 sq. deg|
|AllWISE||WISE||W1, W2, W3, W4||14000 sq. deg|
The fifth data release (DR5 ) includes a portion of DECaLS, covering a disjoint footprint with 7400 deg² in g-band, 8000 deg² in r-band and 10200 deg² in z-band, of which 6800 deg² has been observed in all three optical filters.
The fourth data release (DR4) supplements DR5, and includes for the first time data from MzLS (z band) and BASS (g & r bands). The footprint of DR4 covers ~3600 deg2.
For comparison, the third data release (DR3) included an earlier version of DECaLS with 4300 deg² in g-band, 4600 deg² in r-band, 8100 deg² in z-band, and 4200 deg² in all three optical filters. DR5 supersedes DR3.
In order to obtain the full coverage of the Legacy Survey, one needs to combine both DR5 and DR4. Visit the Data Access page to retrieve Legacy Survey images, and catalogs.