WASHINGTON, USA, Sept. 30, 2026 - NASA launched the Overlap Zoo citizen-science project on 30 September, asking volunteers to identify overlapping pairs of galaxies for research on cosmic dust.^[1] The project confirms galaxy pairs in which one galaxy sits in front of another, revealing the dust between them.^[2] Volunteers look at images first flagged by Galaxy Zoo volunteers,^[3] and when galaxies overlap, light from the background galaxy shines through the foreground one, letting astronomers study its dust.^[4] Anyone with an internet-connected computer can take part.^[5] The project builds on a catalogue of about 800 occulting galaxy pairs from the DESI Legacy Survey, made with citizen science,^[6] led by T. Butrum^[7] and due to be published in the journal PASA.^[8] Space Nugget. Cosmic dust is made of tiny grains of carbon and silicate rock, smaller than the particles in smoke. It absorbs and reddens starlight, so knowing how much dust lies in a galaxy matters for working out how bright, and how far away, its stars really are. Dust is also the raw material from which planets eventually form.