The European Space Agency (ESA) has released the first batch of survey data from its €1.4bn Euclid mission. The release includes a preview of its “deep field” where in just one week of observations, Euclid already spotted 26 million galaxies as well as many transient phenomena such as supernovae and gamma-ray bursts. The dataset is published along with 27 scientific papers that will be submitted to the journal Astronomy & Astrophysics.
The dataset also features a catalogue of 380,000 galaxies that have been detected by artificial intelligence or “citizen-science” efforts. They include those with spiral arms, central bars and “tidal tails”, inferring merging galaxies.
There has also been the discovery of 500 gravitational-lens candidates thanks to AI and citizen science. Gravitational lensing in when light from more distant galaxies is bent around closer galaxies due to gravity and it can help identify where dark matter is located and its properties.
“For the past decade, my research has been defined by painstakingly analysing the same 50 strong gravitational lenses, but with the data release, I was handed 500 new strong lenses in under a week,” says astronomer James Nightingale from Newcastle University. “It’s a seismic shift – transforming how I do science practically overnight.”
The data released today still represents only 0.4% of the total number of galaxies that Euclid is expected to image over its lifetime. Euclid will capture images of more than 1.5 billion galaxies over six years, sending back around 100 GB of data every day.
“Euclid shows itself once again to be the ultimate discovery machine. It is surveying galaxies on the grandest scale, enabling us to explore our cosmic history and the invisible forces shaping our universe,” says ESA’s science director, Carole Mundell. “With the release of the first data from Euclid’s survey, we are unlocking a treasure trove of information for scientists to dive into and tackle some of the most intriguing questions in modern science”.
More data to come
Euclid was launched in July 2023 and is currently located in a spot in space called Lagrange Point 2 – a gravitational balance point some 1.5 million kilometres beyond the Earth’s orbit around the Sun. The Euclid Consortium comprises some 2600 members from more than 15 countries. European Space Agency’s Euclid mission spots spectacular Einstein ring
Euclid has a 1.2 m-diameter telescope, a camera and a spectrometer that it uses to plot a 3D map of the distribution of galaxies. The images it takes are about four times as sharp as current ground-based telescopes.
Euclid released its first images in November 2023 and began routine observations in February 2024, releasing a first data batch in May 2024.
The mission’s first “cosmology data” will be released in October 2026.
