Galaxy Zoo: Morphologies based on UKIDSS NIR Imaging for 71,052 Galaxies

Galaxy Zoo UKIDSS contains morphology measurements for 71,052 galaxies with YJK (1–2.4 μm) imaging from the United Kingdom Infrared Telescope Infrared Deep Sky Survey (UKIDSS). Galaxies were selected out of the Galaxy Zoo 2 (GZ2) sample, so also have classifications based on gri (0.48–0.76 μm) imaging from the Sloan Digital Sky Survey. An identical classification tree, and vote weighting/aggregation was applied to both UKIDSS and GZ2 classifications enabling direct comparisons.

Masters et al. (2024) is an open access RNAAS publication which briefly describes this phase of Galaxy Zoo, which ran from 2013-2014 on the Galaxy Zoo site. Please cite this, and Galloway 2018 (PhD Thesis) if you use these data.

The catalog contains volunteer vote counts (e.g. smooth-or-featured_smooth) and fractions (e.g. smooth-or-featured_smooth_fraction). The CSV and Parquet catalog files contain identical data, just saved in different formats. Each row also includes the subfolder and filename columns, to locate the corresponding image in the tar archive below.

ukidss_images.zip contains 70,845 images, one for each row in the catalog (207 images were not recoverable from our database). The images are in jpg format and exactly as shown to volunteers during GZ UKIDSS.