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- Citizen Science
- Help Overlap Zoo Reveal Cosmic…
Galaxies, vast collections of billions of stars, gas, and dust held together by gravity, are scattered across the immensity of space. But every so often, a coincidence occurs: Two galaxies line up from our point of view on Earth (or from a space telescope) and appear to overlap in the sky. These rare overlapping galaxies give astronomers a chance to study something normally difficult to see: the dust inside one of these distant cosmic objects. That's the focus of NASA's new Overlap Zoo project.
Picture the background galaxy acting like a cosmic flashlight, shining through the nearer galaxy. The backlit dust creates dark silhouettes, like shadows on a screen. By studying these silhouettes, astronomers can map how dust is distributed throughout galaxies and learn how it blocks, scatters, and dims starlight traveling through space. Measurements of how dust impacts light can even help astronomers refine estimates of the distances to faraway objects.
However, before we can study galaxy pairs and their dust, we first need to find them! Overlap Zoo is asking for your help with the search.
