ESA’s first piece of great cosmic map features millions of galaxies in single photo

In July 2023, the European Space Agency (ESA) launched Euclid, a space telescope designed to map the large-scale structure of the universe. Recently, ESA shared a 208-gigapixel mosaic that reveals one percent of the extensive map that Euclid will survey in the next six years.

The large-scale structure of the universe comprises a vast network of galaxies, stars, and dark matter. The mosaic alone features an area in our universe that is more than 500 times the size of the moon.

According to ESA , “This first piece of the map already contains around 100 million sources: stars in our Milky Way and galaxies beyond. Some 14 million of these galaxies could be used to study the hidden influence of dark matter and dark energy on the Universe.”

Also, “This is just 1% of the map, and yet it is full of a variety of sources that will help scientists discover new ways to describe the Universe,” Valeria Pettorino, Euclid Project Scientist at ESA, added.

Zooming into the mosaic

Euclid began its operation in February, and the mosaic is a result of 260 observations recorded between the last week of March and the second week of April 2024.

Thanks to its 600-megapixel sharp and sensitive visible light camera, Euclid captures images with great detail. For instance, when you zoom into the mosaic to 600x, you can clearly spot the core of galactic clusters and see dots turning into beautiful spiral galaxies .

These celestial bodies are located over 400 million light years away from Earth. The complete map, which will be ready in the next six years, will reveal the shapes and movements of galaxies and stars as far as 10 billion light years.

“During this survey, the telescope observes the shapes, distances, and motions of billions of galaxies out to 10 billion light-years. By doing this, it will create the largest cosmic 3D map ever made,” the ESA team said.

Euclid is not limited to stars and galaxies

High in the Earth’s sky, at about 4,500 to 9,000 meters (some sources mention 6,000 m above ground), unique, thin, hair-like clouds are found, called cirrus clouds . They serve important functions such as signaling changes in weather, affecting climate through heat regulation, and contributing to the development of other cloud types.

The mosaic from Euclid spacecraft also reveals the presence of dim clouds that look similar to cirrus clouds. They were spotted in the Milky between stars and are made of cosmic dust and gases. The ESA team refers to them as galactic cirrus.

These structures can reflect light from distant stars, allowing researchers to locate, identify, and study hidden celestial bodies. However, galactic cirrus isn’t the only intriguing finding you will come across in the mosaic.

There could be many other cosmic structures hiding in the mosaic, waiting to be discovered. However, it will take some time before the ESA team zooms into each section of the photo and makes new discoveries.

Moreover, “The mosaic released today is a teaser for what’s to come from the Euclid mission. The release of 53 square degrees of the survey, including a preview of the Euclid Deep Field areas, is planned for March 2025,” the ESA team notes.