In the Dark

Today sees the launch of a new initiative between Galaxy Zoo (part of the Zooniverse conglomerate) and the Euclid Consortium which I am delighted to be able to promote on this blog. What follows the graphic is the text of the announcement which is being promoted across social media today. I’ll start with a little factoid which might surprise you: already in November 2023, before science operations even began, Euclid had sent back to Earth more data than the Hubble Space Telescope has done in in its entire lifetime.

Thanks to a new Galaxy Zoo project launched today, you can help identify the shapes of thousands of galaxies in images taken by ESA’s Euclid space telescope. These classifications will help scientists answer questions about how the shapes of galaxies have changed over time, and what caused these changes and why. 

In its mission to map out the Universe, Euclid will image hundreds of thousands of distant galaxies. In November 2023 and May 2024, the world got its first glimpse at the quality of Euclid’s images, which included a variety of sources, from nearby nebulas to distant clusters of galaxies. In the background of each of these images are hundreds of thousands of distant galaxies. 

For the next six years, the spacecraft is expected to send around 100 GB of data back to Earth every day. That’s a lot of data, and labelling that through human effort alone is incredibly difficult.  

That’s why ESA and Euclid consortium scientists have partnered with Galaxy Zoo. This is a citizen science project on the Zooniverse platform, where members of the public can help classify the shapes of galaxies.  

Euclid will release its first catalogues of data to the scientific community starting in 2025, but in the meantime any volunteer on the Galaxy Zoo project can have a glimpse at previously unseen images from the telescope. 

You could be the first person to lay eyes on a galaxy 

The first set of data, which contains tens of thousands of galaxies selected from more than 800 000 images, has been made available on the platform, and is waiting for you to help classify them. 

If you partake in the project, you could be the first to lay eyes on Euclid’s latest images. Not only that, you could also be the first human ever to see the galaxy in the image.  

The Galaxy Zoo project was first launched in 2007, and asked members of the public to help classify the shapes of a million galaxies from images taken by the Sloan Digital Sky Survey. In the past 17 years, Galaxy Zoo has remained operational, with more than 400 000 people classifying the shapes of galaxies from other projects and telescopes, including the the NASA/ESA Hubble Space Telescope and the NASA/ESA/CSA James Webb Space Telescope.  

Humans and AI working together 

These classifications are not only useful for their immediate scientific potential, but also as a training set for Artificial Intelligence (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 limitless numbers of galaxies. 

At Zooniverse, the team has developed an AI algorithm called ZooBot, which will sift through the Euclid images first and label the ‘easier ones’ of which a lot of examples already exist in previous galaxy surveys. When ZooBot is not confident on the classification of a galaxy, perhaps due to complex or faint structures, it will show it to users on Galaxy Zoo to get their human classifications, which will then help ZooBot to learn more.  

On the platform, volunteers will be presented with images of galaxies and will then be asked several questions, such as “Is the galaxy round?”, or “Are there signs of spiral arms?”. 

After being trained on these human classifications, ZooBot will be integrated in the Euclid catalogues to provide detailed classifications for hundreds of millions of galaxies, making it the largest scientific catalogue to date, and enabling groundbreaking new science.  

This project makes use of the ESA Datalabs digital platform to generate a large number of cutouts of galaxies imaged by Euclid. 

Thanks to a new Galaxy Zoo project launched today, you can help identify the shapes of thousands of galaxies in images taken by ESA’s Euclid space telescope. These classifications will help scientists answer questions about how the shapes of galaxies have changed over time, and what caused these changes and why. 

The first set of data, which contains tens of thousands of galaxies selected from more than 800 000 images, has been made available on the platform, and is waiting for you to help classify them.  

Examples of Euclid galaxies to classify are shown in this image.  

About Euclid 

Euclid was launched in July 2023 and started its routine science observations on 14 February 2024. The goal of the mission is to reveal 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 motions of billions of galaxies out to 10 billion light-years.  

Euclid is a European mission, built and operated by ESA, with contributions 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 for the construction of the satellite and its service module, with Airbus Defence and Space chosen to develop the payload module, including the telescope. NASA provided the detectors of the Near-Infrared Spectrometer and Photometer, NISP. Euclid is a medium-class mission in ESA’s Cosmic Vision Programme.