The start was “perfect”, said the scientific director of the European space agency ESA, Carole Mundell. “In the next six years we will solve the mysteries of the dark side of the universe.”

After launch, it will take Euclid about four weeks to reach its destination 1.5 million kilometers from Earth. The James Webb telescope is located at the so-called Lagrange point 2 between the earth and the sun. From there, Euclid is to measure up to two billion galaxies that cover more than a third of the sky for six years.

The aim is to create a three-dimensional sky map. The telescope will look back ten billion years into the cosmic past to explore the development of the universe and its dark secrets.

The scientific work is scheduled to begin in about three months, once the telescope’s measuring instruments are properly adjusted. The huge amounts of data provided by Euclid are evaluated by around 2,600 researchers from the Euclid consortium, which includes 17 countries. They are then made available to the entire scientific community. The 1.9 billion euro mission should last until at least 2029 or – if all goes well – even longer.