In its mission to measure the universe, the European Space Agency's Euclid space telescope will image billions of distant galaxies. A first impression of the quality of the images Euclid provides was available in November 2023 and May 2024 – ESA published the first images from the space telescope. Hundreds of thousands of galaxies can be seen in the background of each of these images. Over the next six years, the probe is expected to send around 100 GB of data to Earth every day. A very large amount; for this reason, scientists from ESA and the Euclid Consortium have teamed up with Galaxy Zoo, a Citizen Science project on the Zooniverse platform where the public can help classify the shapes of galaxies. The Euclid Consortium will make its first data catalogs available to the scientific community starting in 2025, but until then, any volunteer participating in the Galaxy Zoo project can take a look at previously unseen images from the telescope and help classify the galaxies it captures.
People and AI work together
These classifications are useful not only for their immediate scientific potential, but also as training material for AI algorithms. Without being taught what to look for by humans, AI algorithms struggle to classify galaxies. But together, humans and AI can accurately classify an unlimited number of galaxies. The Zooniverse team has developed an AI algorithm called ZooBot that first sifts through the Euclid images and flags the "easier" galaxies, of which there are already many examples in previous galaxy surveys. When ZooBot is unsure about how to classify a galaxy, for example because of complex or weak structures, it shows it to Galaxy Zoo users to get human classifications that in turn help ZooBot learn.
On the platform, volunteers are shown images of galaxies and then asked various questions, such as "Is the galaxy round?" or "Is there evidence of spiral arms?". After being trained on these human classifications, ZooBot will be integrated into the Euclid catalogs to provide detailed classifications for hundreds of millions of galaxies. This will create the largest scientific catalog of galaxies to date, enabling groundbreaking new science.
Participate now
"This Zooniverse project helps us characterize the shape and structure of hundreds of millions of galaxies over cosmic time. It is of great importance because it uses the possibilities of Citizen Science and combines them with artificial intelligence to improve our understanding of the formation and evolution of galaxies," emphasizes Prof. Francine Marleau from the Institute for Astro- and Particle Physics. She is a member of the Euclid Consortium and heads the scientific working group "Local Universe" and coordinates a "Data Release 1" (DR1) Key Project. She is also a member of the "Galaxy and AGN Evolution" and "Milky Way Resolved Stellar Population" working groups.
The first dataset, with tens of thousands of galaxies selected from more than 800,000 images, is available on the platform and waiting to be classified by interested parties. Those who participate in the project will be among the first people ever to see the latest images from Euclid and may even be the first person to see the specific galaxy in the image.
For more information on how to participate, visit the Galaxy Zoo website: https://www.zooniverse.org/projects/zookeeper/galaxy-zoo/
About Euclid
Euclid was launched in July 2023 and began its scientific observations on February 14, 2024. The goal of the mission is to uncover the hidden influence of dark matter and dark energy on the visible universe. Over a period of six years, Euclid will observe the shapes, distances and movements of billions of galaxies within a range of 10 billion light years.
Euclid is a European mission built and operated by ESA, with participation from NASA. The Euclid Consortium – consisting of more than 2000 scientists from 300 institutes in 15 European countries, the USA, Canada and Japan – is responsible for providing the scientific instruments and scientific data analysis. ESA selected Thales Alenia Space as prime contractor to build the satellite and its service module, while Airbus Defence and Space was contracted to develop the payload module, including the telescope. NASA provided the Near-Infrared Spectrometer and Photometer (NISP) detectors. Euclid is a medium-class mission under ESA's Cosmic Vision programme.