Overlap Zoo

Welcome to Overlap Zoo!

With your help, we can classify special systems known as overlapping galaxy pairs. In these rare cosmic overlaps, a foreground galaxy serendipitously overlaps a more distant one. Acting as a natural backlight, the distant background galaxy reveals hidden dusty structures in the closer foreground galaxy with remarkable detail. These rare overlaps thus provide a unique opportunity to measure the dust distribution in a foreground galaxy with great accuracy, helping aid our understanding of the critical role dust plays in our observations and measurements. Your classifications will help us categorize these pairs and identify ideal candidates for future detailed dust studies.

Our ideal pair consists of a foreground, symmetrical spiral galaxy overlaying a background, symmetrical, smooth galaxy. Thanks to this symmetry in both pairs, we can apply rotational and modelling techniques that help us isolate and measure the distribution of dust in the foreground galaxy. A prime example of an ideal pair, which you may have seen, is the recently imaged VV191a/b pair.

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This project is soon to be supported by NASA's Citizen Science Seed Funding Program (CSSFP). For more projects, see: science.nasa.gov/citizenscience. For other ways to get involved, see: https://www.nasa.gov/get-involved/.