Siena Galaxy Atlas¶
The Siena Galaxy Atlas (SGA) is a multiwavelength, diameter-limited atlas of nearby galaxies built using the DESI Legacy Imaging Surveys (the Legacy Surveys). For each galaxy, the SGA delivers precise coordinates, multiwavelength mosaics, azimuthally averaged surface-brightness and color profiles, integrated and aperture photometry, and additional metadata. Because large, resolved galaxies trace the foreground extragalactic sky, the SGA also serves as a foundational reference catalog for wide-field cosmological surveys such as the Dark Energy Spectroscopic Instrument (DESI).
Current release (v1.0) — ~486,000 galaxies over 30,000 deg²
griz optical (DR11) · unWISE W1–W4 · GALEX FUV/NUV
Data model, catalog access, and per-group file inventory.
Web gallery (draft): dr11-north · dr11-south
383,620 galaxies · grz optical (DR9) · unWISE W1–W4
Released January 2021.
Getting Started
Data Releases