Galaxy Zoo 1 data release

The original Galaxy Zoo project ran from July 2007 until February 2009. It was replaced by Galaxy Zoo 2, Galaxy Zoo: Hubble, and Galaxy Zoo: CANDELS. In the original Galaxy Zoo project, volunteers classified images of Sloan Digital Sky Survey galaxies as belonging to one of six categories - elliptical, clockwise spiral, anticlockwise spiral, edge-on , star/don't know, or merger.

Full catalog

This webpage allows anyone to download the resulting GZ classifications of nearly 900,000 galaxies in the project.

Galaxy Zoo is described in Lintott et al. 2008, MNRAS, 389, 1179 and the data release is described in Lintott et al. 2011, 410, 166. Anyone making use of the data should cite at least one of these papers in any resulting publications.

This table gives classifications of galaxies which have spectra included in SDSS Data Release 7. The fraction of the vote in each of the six categories is given, along with debiased votes in elliptical and spiral categories and flags identifying systems as classified as spiral, elliptical or uncertain.
CSV (gzipped)http://galaxy-zoo-1.s3.amazonaws.com/GalaxyZoo1_DR_table2.csv.gz
CSV (zip)http://galaxy-zoo-1.s3.amazonaws.com/GalaxyZoo1_DR_table2.csv.zip
FITShttp://galaxy-zoo-1.s3.amazonaws.com/GalaxyZoo1_DR_table2.fits
VOTablehttp://galaxy-zoo-1.s3.amazonaws.com/GalaxyZoo1_DR_table2.vot.gz
Note: the provided flags in Table 2 are there for the convenience of users who do not want to get into the details too much. These are based upon a vote fraction threshold of 0.8. However, there is a complication in the debiasing (described in Bamford et al. 2009). The classification bias depends on whether one uses the type likelihoods directly, or applies a threshold. The bias is worse if thresholds are used. We therefore applied bias corrections computed in consistent fashion. So, for the debiased type likelihoods we computed the bias correction based on the elliptical/spiral ratio using the likelihoods directly; for the type flags we debiased the raw type likelihoods using a correction based on the elliptical/spiral ratio determined after applying a 0.8 threshold, and then applied the same threshold to produce the flags. Therefore, the type flags do not correspond to simply applying a 0.8 threshold on the debiased type likelihoods, though for many galaxies these will agree.

This table gives classifications of galaxies included in the Galaxy Zoo sample which did not have spectra available in SDSS Data Release 7. It is not possible to estimate the bias in this sample without accurate redshifts, and so only the fraction of the vote in each of the six categories is given.
CSV (gzipped)http://galaxy-zoo-1.s3.amazonaws.com/GalaxyZoo1_DR_table3.csv.gz
CSV (zip)http://galaxy-zoo-1.s3.amazonaws.com/GalaxyZoo1_DR_table3.csv.zip
FITShttp://galaxy-zoo-1.s3.amazonaws.com/GalaxyZoo1_DR_table3.fits
VOTablehttp://galaxy-zoo-1.s3.amazonaws.com/GalaxyZoo1_DR_table3.vot.gz

This table gives a series of measures of the classification confidence.
CSV (gzipped)http://galaxy-zoo-1.s3.amazonaws.com/GalaxyZoo1_DR_table4.csv.gz
CSV (zip)http://galaxy-zoo-1.s3.amazonaws.com/GalaxyZoo1_DR_table4.csv.zip
FITShttp://galaxy-zoo-1.s3.amazonaws.com/GalaxyZoo1_DR_table4.fits
VOTablehttp://galaxy-zoo-1.s3.amazonaws.com/GalaxyZoo1_DR_table4.vot.gz

This table gives the results from the bias study that introduced mirrored images.
CSV (gzipped)http://galaxy-zoo-1.s3.amazonaws.com/GalaxyZoo1_DR_table5.csv.gz
CSV (zip)http://galaxy-zoo-1.s3.amazonaws.com/GalaxyZoo1_DR_table5.csv.zip
FITShttp://galaxy-zoo-1.s3.amazonaws.com/GalaxyZoo1_DR_table5.fits
VOTablehttp://galaxy-zoo-1.s3.amazonaws.com/GalaxyZoo1_DR_table5.vot.gz

This table gives the results from the bias study that introduced monochrome images.
CSV (gzipped)http://galaxy-zoo-1.s3.amazonaws.com/GalaxyZoo1_DR_table6.csv.gz
CSV (zip)http://galaxy-zoo-1.s3.amazonaws.com/GalaxyZoo1_DR_table6.csv.zip
FITShttp://galaxy-zoo-1.s3.amazonaws.com/GalaxyZoo1_DR_table6.fits
VOTablehttp://galaxy-zoo-1.s3.amazonaws.com/GalaxyZoo1_DR_table6.vot.gz

This table gives the fraction of votes in each of the six categories, combining results from the main and bias studies.
CSV (gzipped)http://galaxy-zoo-1.s3.amazonaws.com/GalaxyZoo1_DR_table7.csv.gz
CSV (zip)http://galaxy-zoo-1.s3.amazonaws.com/GalaxyZoo1_DR_table7.csv.zip
FITShttp://galaxy-zoo-1.s3.amazonaws.com/GalaxyZoo1_DR_table7.fits
VOTablehttp://galaxy-zoo-1.s3.amazonaws.com/GalaxyZoo1_DR_table7.vot.gz

CASjobs

These tables are also accessible via CasJobs. Their names are:

  • Table 2: DR10.zooSpec
  • Table 3: DR10.zooNoSpec
  • Table 4: DR10.zooConfidence
  • Table 5: DR10.zooMirrorBias
  • Table 6: DR10.zooMonochrome
  • Table 7: DR10.zooVotes

AGN host galaxies

This sample is presented in the Galaxy Zoo 1 paper on AGN host galaxies (Schawinski et al., 2010, ApJ, 711, 284). It is a volume-limited sample of galaxies (0.02 < z < 0.05, Mz < –19.5 AB) with emission line classifications, stellar masses, velocity dispersions and GZ1 morphological classifications. When using this sample, please cite Schawinski et al. (2010) and Lintott et al. (2008, 2011).

Download here: http://galaxy-zoo-1.s3.amazonaws.com/schawinski_GZ_2010_catalogue.fits.gz

OBJIDSDSS DR7 object ID
RA, DECRA and dec in J2000.0
REDSHIFTspectroscopic redshift from SDSS
GZ1_MORPHOLOGYGalaxy Zoo 1 morphology according to the Land et al. (2008) "clean" criterion. This is an integer where 0 = indeterminate, 1 = early type, 3 = merger, 4 = late type
BPT_CLASSSpectroscopic classification of galaxy based on emission lines ratios in the BPT diagram. 0 = no emission lines, 1 = star-forming, 2 = composite, 3 = Seyfert and 4 = LINER.
U,G,R,I,ZSDSS model magnitudes. These are extinction-corrected but not k-corrected.
SIGMA, SIGMA_ERRStellar velocity dispersion (and error) measured using GANDALF
LOG_MSTELLARlog of stellar mass [M_sun]
L_O3Extinction-corrected [OIII] luminosity

Overlapping Galaxy Pairs

This section contains data from the Galaxy Zoo survey for overlapping galaxy pairs, useful for studies of dust absorption. Data is derived from the Zoo 1 and Zoo 2 periods (August 2007–April 2010), and is described in detail by Keel et al. (PASP, 2013, 125, 923). The catalog contains a total of 1990 galaxy pairs.

Column description and format
TXToverlapcatalog.txt
JavascriptOverlap candidates (sortable webpage)

There is a similar file of candidate pairs which were rejected for the final list because of evidence for interaction, other geometric reasons, or for having redshifts the wrong way around for dust backlighting.

PDF OverlapRejects.pdf
Javascript Overlap rejects (sortable webpage)

The various overlapping galaxy pair types are illustrated in Figures 2a and 2b from Keel et al. 2013. Below are PDF files containing a single page for each galaxy pair, plus finding charts, more detailed photometry and identifications, and in some cases more precise redshifts. The PDFs are also available at http://astronomy.ua.edu/keel/observe/PDFcharts.

SDSSOverlaps00Final.pdf RA: 00–10 hours
SDSSOverlaps10final.pdf RA: 10–13 hours
SDSSOverlaps13final.pdf RA: 13–15 hours
SDSSOverlaps15final.pdf RA: 15–24 hours

Merging galaxies

This sample of merging galaxies is assembled from SDSS Galaxy Zoo 1 data. It is a homogenous sample of galaxies (0.005 < z < 0.1) with spectroscopy for at least one of two merging galaxies in the pair. Value-added GZ data includes the morphologies of the merging galaxies as well as the relative stage of the merger. For any use of data from this sample, please cite Darg et al. (2010a) and Darg et al. (2010b).

Column description and format
CSVdarg_mergers.csv
FITSdarg_mergers.fits

Galaxy Zoo 2

Galaxy Zoo 2 (GZ2) was the successor project to Galaxy Zoo. GZ2 extends the original Galaxy Zoo classifications for a subsample of the brightest and largest galaxies in the Legacy release, measuring more detailed morphological features. This includes galactic bars, spiral arm and pitch angle, bulges, edge-on galaxies, relative ellipticities, and many others.

Full Catalog

These tables provide the GZ2 classifications for nearly 300,000 galaxies in the SDSS.

The project description and data reduction is in Willett et al. (2013) — please cite this paper if making any use of the GZ2 data. The table numbers below are the same as their order in the paper.


Table 5 gives classifications of the 243,500 galaxies in the main sample with spectroscopic redshifts. This is the primary GZ2 data release, containing the largest number of galaxies and the most reliable morphologies.
Column description and format
CSVhttp://zooniverse-data.s3.amazonaws.com/galaxy-zoo-2/zoo2MainSpecz.csv.gz
FITShttp://zooniverse-data.s3.amazonaws.com/galaxy-zoo-2/zoo2MainSpecz.fits.gz
VOTablehttp://zooniverse-data.s3.amazonaws.com/galaxy-zoo-2/zoo2MainSpecz.vot.gz

Table 6 gives classifications of the 42,462 galaxies in the main sample with photometric redshifts only. Debiased morphologies for this sample are slightly more uncertain than Table 5, since the data reduction requires a redshift to adjust the morphology for classification bias.
Column description and format
CSVhttp://zooniverse-data.s3.amazonaws.com/galaxy-zoo-2/zoo2MainPhotoz.csv.gz
FITShttp://zooniverse-data.s3.amazonaws.com/galaxy-zoo-2/zoo2MainPhotoz.fits.gz
VOTablehttp://zooniverse-data.s3.amazonaws.com/galaxy-zoo-2/zoo2MainPhotoz.vot.gz

Table 7 gives classifications of the 17,787 galaxies classified in single-depth Stripe 82 images. The magnitude limit for Stripe 82 classifications (r<17.7) is slightly deeper than the main samples. Some of these galaxies also appear in the main sample (Table 5).
Column description and format
CSVhttp://zooniverse-data.s3.amazonaws.com/galaxy-zoo-2/zoo2Stripe82Normal.csv.gz
FITShttp://zooniverse-data.s3.amazonaws.com/galaxy-zoo-2/zoo2Stripe82Normal.fits.gz
VOTablehttp://zooniverse-data.s3.amazonaws.com/galaxy-zoo-2/zoo2Stripe82Normal.vot.gz

Table 8 gives classifications of the first set of 19,765 galaxies classified in the coadded (runs 106 and 206) Stripe 82 images. Coadded images are made from combining between 47–55 individual exposures, resulting in better detection of fainter features and improved seeing. This set of images had no adjustments made to its background, which resulted in coloured background noise for some galaxies.
Column description and format
CSVhttp://zooniverse-data.s3.amazonaws.com/galaxy-zoo-2/zoo2Stripe82Coadd1.csv.gz
FITShttp://zooniverse-data.s3.amazonaws.com/galaxy-zoo-2/zoo2Stripe82Coadd1.fits.gz
VOTablehttp://zooniverse-data.s3.amazonaws.com/galaxy-zoo-2/zoo2Stripe82Coadd1.vot.gz

Table 9 gives classifications of the second set of 19,761 galaxies classified in the coadded (runs 106 and 206) Stripe 82 images. Coadded images are made from combining between 47–55 individual exposures, resulting in better detection of fainter features and improved seeing. This set of images applied a modest colour desaturation to de-emphasise background noise in the coadded data.
Column description and format
CSVhttp://zooniverse-data.s3.amazonaws.com/galaxy-zoo-2/zoo2Stripe82Coadd2.csv.gz
FITShttp://zooniverse-data.s3.amazonaws.com/galaxy-zoo-2/zoo2Stripe82Coadd2.fits.gz
VOTablehttp://zooniverse-data.s3.amazonaws.com/galaxy-zoo-2/zoo2Stripe82Coadd2.vot.gz

This table provides pre-matched sets of metadata for the Galaxy Zoo 2 samples taken from DR7. This includes coordinates, photometry, size, and redshifts (where present). For science cases, we encourage users to instead use the latest measurements from DR10.
Column description and format
CSVhttp://zooniverse-data.s3.amazonaws.com/galaxy-zoo-2/gz2sample.csv.gz
FITShttp://zooniverse-data.s3.amazonaws.com/galaxy-zoo-2/gz2sample.fits.gz
VOTablehttp://zooniverse-data.s3.amazonaws.com/galaxy-zoo-2/gz2sample.vot.gz

The code used to reduce GZ2 is available on GitHub — please take a look either at its webpage or fork it from the repository if you're interested in the details.

CASjobs

The GZ2 catalog is also accessible via CasJobs in Data Release 10. The table names in CasJobs are:

  • Table 5: DR10.zoo2MainSpecz
  • Table 6: DR10.zoo2MainPhotoz
  • Table 7: DR10.zoo2Stripe82Normal
  • Table 8: DR10.zoo2Stripe82Coadd1
  • Table 9: DR10.zoo2Stripe82Coadd2

SDSS Skyserver

For any object in SDSS DR10, you can access its Galaxy Zoo or Galaxy Zoo 2 classifications (if present) by using the "Explore" tool. Just click the "Galaxy Zoo" link under "Imaging Summary" in the left-hand sidebar (example here).

Bar lengths

In conjunction with Galaxy Zoo 2, we ran a parallel project to measure lengths, widths, and angles of galactic bars using an interactive interface. See Hoyle et al. (2011) for a description of the project and scientific results. The full set of results can be downloaded below.


CSVbarlengths.csv
FITSbarlengths.fits
VOTablebarlengths.vot

Dust-lane spheroidal galaxies

Early Galaxy Zoo 2 classifications were used to identify a sample of 362 spheroidal galaxies with prominent dust lanes (DLSGs), ranging from redshifts of z=0.01 to 0.07. Catalogues of the galaxy properties, along with multi-wavelength coverage from radio through ultraviolet, are available here.

All tables below are in ASCII format.

Please cite the DLSG (Kaviraj et al. 2012; Shabala et al. 2012; Kaviraj et al. 2013) and Galaxy Zoo 2 (Willett et al. 2013) publications if using this data.


Galaxy Zoo: Hubble

Galaxy Zoo: Hubble used data from the Hubble Space Telescope to classify images of galaxies at higher redshifts. Images were taken from the Advanced Camera for Surveys (ACS) aboard Hubble, comprising data from the GEMS, GOODS-N, and AEGIS surveys.

Full catalog

The full data reduction and analysis of GZ: Hubble is in progress.

Bar fraction evolution

In Melvin et al. (2014), we use GZ2 and preliminary GZ: Hubble data to study the evolution of the bar fraction in galaxies over cosmic timescales. Presented here are links to webpages with the HST postage stamp images for the different galaxy samples.

Shown here is a diagram of the classification scheme and decision tree used in GZ: Hubble.