I chose Galaxy Zoo for my Crowdsourcing Project because Astronomy is second only to history for me as a subject of fascination. Galaxy Zoo crowdsources the vast amount of data gathered for Physical Cosmology, the study of galaxy formation and evolution. Since there are billions of galaxies in the universe, scientists cannot classify each pictured object themselves.
The project has users go through captured images such as the one pictured above and classify them based on the criteria provided. The answers for this particular image, for example, are: Spiral galaxy, not edge-facing, visible central bulge that is rounded rather than bar-shaped, 3 visible arms that are tightly compacted, and there is a sign of tidal debris at the bottom left where another, smaller galaxy may be merging.
Many different participants view the same galaxy, and if a person notes something odd or peculiar, the survey will ask the next person about that as well as the general questions. This is a way of “fact-checking” before scientists accept any generalized assessments or use telescope time to view notable galaxies more closely. It is not rare that 100% of respondents agree.
The data gathered here is used by scientists to learn about galaxy formation and evolution, who can use the answers in the context of where the galaxies are and how distant (and therefore, how old) they are. In addition, by measuring distances and frequency of clusters/mergers/types of galaxies, astronomers are also using this data to study the nature and effects of the mysterious “dark energy” that appears to be accelerating cosmic expansion. This is history in the most profound sense: the history of the 13.5 billion years of the universe’s existence and attempts to predict its future.