The Science Programme Committee of the European Space Agency (ESA) on Tuesday gave its final approval to the Euclid space telescope programme. The cost of the development of the telescope, its instruments, its launch and operation will probably exceed €800-million.

“This formal adoption of the mission is a major milestone for a large scientific community, their funding agencies and also for European industry,” stated ESA Directorate of Science and Robotic Exploration director Alvaro Giménez Cañete. The telescope should be completed in 2019 and launched in 2020.

Euclid will be equipped with a 1.2-m-diameter telescope, a visible wavelength camera and a near infrared camera/spectrometer. The US National Aeronautics and Space Administration will have a 5% share in Euclid and will help provide infrared detectors for the spacecraft.

The space telescope is intended to expand human knowledge of dark matter and dark energy.

Dark matter, so called because it is not directly visible to humans or instruments, makes up about 25% of the universe. It is known to exist because its gravitational effects on visible matter are observable.

Dark energy makes up about 70% of the universe and is even more mysterious. It is the phenomenon that is driving the expansion of the universe.

Euclid will cover one-third of the sky and chart the three-dimensional distribution of as many as two-billion galaxies over a distance of ten-billion light years (meaning it will look ten-billion years into the past).

All galaxies and galaxy clusters are associated with dark matter – they can only keep their shapes because of the gravity from this mysterious substance. Similarly, a study of galaxies and galaxy clusters so deep into the past will hopefully reveal the effects of dark energy upon them.

The aim is to use data about visible matter to provide further and more detailed clues about the nature of dark matter and dark energy. Data from Euclid will be supplied to some 1 000 scientists in 100 institutions, grouped together as the Euclid Consortium. Not all these scientists and institutions will be in Europe.