REF2014 Impact Case Study: Impact of Galaxy Zoo and the Zooniverse on Public Engagement with Scientific Research

Impact: Educational Impacts (beyond UoP), Cultural & Creative Impacts

Description of impact

Galaxy Zoo (GZ) is among the most successful online citizen science project ever undertaken, relying on hundreds of thousands of volunteers to classify galaxy images. Since 2007, GZ has evolved into a “Zooniverse” of over 20 online projects, engaging nearly a million worldwide volunteers (from a range of ages, backgrounds and education) in scientific research.

Who is affected

General public


It is impossible to visually inspect each galaxy in massive digital imaging datasets like the Sloan Digital Sky Survey (SDSS), and modern, computer-based algorithms cannot yet unambiguously determine whether a galaxy is spiral or elliptical. This makes it difficult to uncover the true evolutionary history of galaxies. Galaxy Zoo (GZ) was inspired by this limitation. Samples of elliptical galaxies from the initial SDSS, by Bob Nichol and collaborators, relied on imperfect computer-based correlations. To circumvent this challenge, Daniel Thomas, Claudia Maraston, and collaborators at Oxford University built a complete sample of elliptical galaxies based solely on their appearance.
Galaxy Zoo (GZ) is one of the most successful “citizen science” projects ever undertaken, inspiring the creation of the GZ internet forum, through which several rare classes of object were discovered by the public, and several volunteer scientific projects. The GZ forum boasts more than half a million postings on nearly 18,000 topics (as of April 2013) and the GZ blog has become the main mechanism by which scientists communicate with volunteers to provide updates on the academic research being done with their classifications. Over the last year (2012-13), the Zooniverse blogs have attracted 86,000 unique viewings. Most GZ volunteers report being motivated by a desire to contribute to real research, while 87% say their experience has changed their behaviour e.g. more museum visits (34%). For under-18s, 70% were encouraged to study a degree and 47% said GZ helped their schoolwork.
Galaxy Zoo has emphatically demonstrated the power of citizen science, and has inspired new and exciting projects. There are now several commercially-orientated citizen science projects underway.
Impact statusOpen
Category of impactEducational Impacts (beyond UoP), Cultural & Creative Impacts
Impact levelBenefit (delivered impact)


  • citizen science
  • universe
  • galaxies


  • REF2014