Happy Data Release Day: DECaLS goes live

I’m delighted to say that – with the release of the accompanying paper on the arXiv – the first data release from our Galaxy Zoo classifications of galaxies from the DECaLS survey is now live! The paper is still under review at the journal, but as lead author Mike Walmsley is handing in his thesis (congratulations!) it seemed like a good time to release the data.

As the title suggests, this data relies on classifications submitted by our wonderful Galaxy Zoo volunteers from 2015 to 2020, particularly via the ‘Enhanced’ workflow where classifications are used to educate a friendly robot assistant, speeding up the process dramatically. As a result, we have detailed classifications for 314,000 galaxies based on deeper imaging than we’ve ever had before.

The results are dramatic! In the figure above you can see a comparison between the fraction of votes a galaxy received for being ‘featured’ in our previous data release, compared to with the new DECaLS imaging. If the new imaging made no difference, the galaxies would all lie on the dotted line, but they’re mostly above it – volunteers are seeing more features in galaxies in deeper imaging. All of which makes sense, but it’s still gratifying.

We’re all looking forward to getting stuck into this dataset – and Mike has built a tool for you to explore with. Using this interface, you can sort through the data and look at the results – below is a quick sample of double rings Sandor cooked up in no time at all.

We’re not done by a long shot – unlike these systems, the galaxies currently awaiting your inspection over at GalaxyZoo.org have not been previously classified – with your help, hopefully it won’t be too long before we can add them to the catalogue. In the meantime – thanks for all your help!

Chris

P.S. Pulling this paper together was a real team effort so I want to thank each and every one of the team for their hard work getting this over the line. We haven’t forgotten the volunteers either – the final, published version will have an author list online with the names of everyone who contributed and we’ll email you all a link.